CN113929379A

CN113929379A - Bamboo concrete and preparation method thereof and pavement paving construction method of bamboo concrete

Info

Publication number: CN113929379A
Application number: CN202111092236.9A
Authority: CN
Inventors: 刘文胜; 胡石卫; 罗桂军; 梁文新; 张胥; 程敏; 向官清; 何世林; 黄华祥
Original assignee: CCFEB Civil Engineering Co Ltd
Current assignee: CCFEB Civil Engineering Co Ltd
Priority date: 2021-09-17
Filing date: 2021-09-17
Publication date: 2022-01-14
Anticipated expiration: 2041-09-17
Also published as: CN113929379B

Abstract

The invention discloses bamboo concrete and a preparation method thereof and a pavement paving construction method of the bamboo concrete, wherein the pavement paving construction method comprises the following steps: the mass ratio of the cement to the sand to the broken stone to the bamboo chips to the thin bamboo strips to the water reducing agent is (335-347), to (667-707), to (1185-1257), to (0.357-0.363), to (1.783-1.817), to (146-148) to (3.04-5.17). The bamboo concrete solves the problems of low bending tensile strength, brittleness, easy fracture, poor durability and short service life of a cement concrete pavement, avoids the problems of high production cost of steel fiber concrete and poor temperature stability of asphalt concrete due to asphalt materials, and has the advantages of recycling bamboo materials with low price, energy conservation, environmental protection, reinforcement and toughening, protecting resource environment, reducing pollution of wastes, reducing the construction cost of a road or a terrace pavement, along with simple and convenient construction process operation and convenient wide application.

Description

Bamboo concrete and preparation method thereof and pavement paving construction method of bamboo concrete

Technical Field

The invention relates to the field of road or terrace pavement construction, in particular to bamboo concrete. In addition, the invention also relates to a preparation method of the bamboo concrete and a pavement paving construction method of the bamboo concrete.

Background

With the rapid development of facilities such as highways, urban and rural roads, industrial factories and mines or factory buildings, roads or terrace pavements are important components of engineering construction, and bear the long-term effects of static and dynamic loads of vehicles or equipment directly, and the driving safety and equipment safety of the vehicles are directly influenced by the quality of pavement construction.

The traditional construction method of road or terrace pavement is to construct cement concrete, steel fiber concrete and asphalt concrete on the top surface of a pavement structure base layer. In the traditional construction method, the cement concrete pavement is of a rigid material pavement structure, for example, a pavement structure base or a lower base thereof is settled, so that the rigid cement concrete pavement is subjected to brittle fracture, and the driving safety and equipment safety of a vehicle are seriously affected; the steel fiber concrete has higher production cost, and is generally inconvenient to be widely used except for special environment requirements; the asphalt concrete has the defects that the temperature stability of the asphalt material is poor, the pavement is cracked due to embrittlement in winter, and the asphalt concrete is easy to soften in summer to form tracks.

Natural bamboo is mainly used as a woven handicraft and a fuel. The utilization rate of a complete bamboo woven handicraft article is 70%, and the rest 30% of the bamboo woven handicraft article is used as fuel, so that useless waste is changed to pollute the environment. But the research of applying bamboo as a building material to engineering construction is extremely rare.

Disclosure of Invention

The invention provides bamboo concrete, a preparation method thereof and a pavement paving construction method of the bamboo concrete, and aims to solve the technical problems of low flexural tensile strength, brittleness, easy fracture, poor durability, short service life, high production cost of steel fiber concrete and poor temperature stability of asphalt concrete due to asphalt materials of a cement concrete pavement.

The technical scheme adopted by the invention is as follows

A bamboo concrete comprising: the mass ratio of the cement to the sand to the broken stone to the bamboo chips to the thin bamboo strips to the water reducing agent is (335-347), to (667-707), to (1185-1257), to (0.357-0.363), to (1.783-1.817), to (146-148) to (3.04-5.17). Unit is kg/m³。

Furthermore, the crushed stone comprises crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm; the mass ratio of crushed stone with the granularity of 4.75-9.5 mm to crushed stone with the granularity of 9.5-19 mm is (557-591): (628-666). Mixing the crushed stones into a median determination method: mixing and synthesizing crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm in a saturated surface-dry state according to four proportions of 62 percent to 38 percent, 52 percent to 48 percent, 42 percent to 58 percent and 32 percent to 68 percent in percentage by mass respectively, and performing screening test detection respectively to obtain reasonable fluctuation of 42-52 percent to 58-48 percent in percentage by massIn the blending proportion range, the medium values (namely 47 percent to 53 percent in mass percentage) of the upper limit value and the lower limit value of the reasonable fluctuation blending proportion are respectively blended into 4.75-19 mm synthetic graded crushed stone, so that the quality control of the crushed stone blending synthesis during the on-site concrete blending is facilitated, and the stability of the on-site crushed stone grading is further ensured. Unit is kg/m³。

Further, the bamboo wood concrete with the air temperature of 10 +/-5 ℃ in the air temperature section comprises: the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (3.04-3.10). And/or the bamboo wood concrete with the air temperature of 20 +/-5 ℃ in the air temperature section comprises: the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (4.05-4.13). And/or the bamboo wood concrete with the air temperature of 30 +/-5 ℃ in the air temperature section comprises: the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin-bamboo-strip filaments, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (5.07-5.17). On the basis of the bamboo concrete in the temperature range of 20 +/-5 ℃, 20 +/-5 ℃ and 30 +/-5 ℃, the unit dosage of cement, sand, gravel, bamboo chips, bamboo filaments and mixing water is kept unchanged, and the mass mixing amount of the water reducing agent is respectively reduced or increased by 0.3 percent to obtain the bamboo concrete in the temperature range of 10 +/-5 ℃ and 30 +/-5 ℃ so as to meet the requirement of paving construction of pavement concrete in the temperature range of 5-35 ℃. Unit is kg/m³。

Furthermore, the granularity of the bamboo dust is less than or equal to 0.6 mm. And/or the thin bamboo strips are 15 mm-20 mm in length, 2.0 mm-3.0 mm in width and 1.0 mm-1.5 mm in thickness. And/or the surface shape of the thin bamboo strip is one or more of a strip shape, a trapezoid shape, a needle point shape, an arrow tail shape and an oval shape. The bamboo split filaments are the outer layer of bamboo stalks. Adopts natural organic fiber with clean outer surface, green and environment-friendly Sagittaria sagittifolia with bamboo stalk fiber toughness for more than 3 years. Bamboo scraps are formed by sawing bamboo stalks of Sagittaria sagittifolia for more than 3 years into bamboo scraps, and the granularity of the bamboo scraps is 30 meshes. The bamboo skin filaments are made of natural organic fibers with clean outer surfaces, green and environment-friendly bamboo with strong bamboo stalk fiber toughness for more than 3 years. And stripping and cutting bamboo strips from Ci bamboo stalks for more than 3 years to obtain the bamboo skin filaments. The concrete mixture is prepared by mixing the bamboo skin wires of five samples of which the lengths are 5-10 mm, 10-15 mm, 15-20 mm, 20-25 mm and 25-30 mm after surface soaking treatment and draining with cement concrete indoor reference design components respectively, the workability, segregation, bleeding and the dispersibility of the concrete mixture are comprehensively analyzed, the length of the selected bamboo skin wires does not exceed the maximum particle size of broken stones, the phenomenon that the bamboo skin wires are too long is prevented, the bamboo concrete mixture is easy to stir into clusters and is not dispersed, the number of local bamboo skin wires in the bamboo concrete is small, and various mechanical properties of the bamboo concrete are influenced. Finally, the thin bamboo strips with the length of 15-20 mm, the width of 2.0-3.0 mm and the thickness of 1.0-1.5 mm are determined to be adopted. The bamboo skin silk appearance is one or several of rectangular shape, trapezoidal, pinpoint shape, arrow tail shape, oval, is special-shaped structure, helps bonding between with the concrete, strengthens the adhesive force between bamboo skin silk and the concrete, makes the ductility and the bending resistance of concrete obtain obviously improving, blocks the expansion of the adjacent concrete crack of bamboo skin silk.

The cement is red lion P.O42.5 ordinary portland cement. The sand is river sand which is hard, durable and clean. The broken stone is single-particle-grade broken stone with the granularity of 4.75-9.5 mm and the granularity of 9.5-19 mm, which is prepared from hard, durable and clean limestone through crushing and processing. The water reducing agent is BX-II type retarding high-efficiency water reducing agent, powder, the water reducing rate is 22%, and the mass mixing amount is 1.2% of the mass of the cement. The mixing water is drinking water meeting the national standard.

As shown in fig. 1, according to another aspect of the present invention, there is also provided a method for preparing bamboo concrete, comprising the following steps:

s1, inspecting the composition materials of the bamboo wood concrete, wherein the composition materials comprise: cement, sand, rubble, bamboo bits, thin bamboo strips used for weaving silk, water and water-reducing agent, the inspection includes: inspecting cement, sand, broken stone and processing into single-grain broken stone, inspecting bamboo chips, bamboo split filaments, a water reducing agent and mixing water;

s2, preparing indoor standard design components of the cement concrete, including: preparing a composition material sample, mixing and synthesizing broken stones, inspecting quality, designing and calculating components of cement concrete, performing indoor trial mixing and quality inspection on the components of the cement concrete, and determining indoor reference design components of the cement concrete;

s3, preparing bamboo concrete indoor design components, including: preparing bamboo scraps and bamboo skin filaments, designing and calculating bamboo concrete components, performing indoor trial mixing and quality inspection on the bamboo concrete components, and determining indoor designed components of the bamboo concrete;

s4, performing mixing verification of the bamboo wood concrete mixing station at the mixing station according to indoor design components of the bamboo wood concrete, and performing comparative analysis with test detection results of the indoor design components of the bamboo wood concrete;

s5, preparing bamboo wood concrete pavement component design components, and determining the concrete pavement component design components in the three air temperature sections.

Further, the preparation of the bamboo chips and thin bamboo strips in the step S3 includes the following steps: (1) determining the length and unit dosage of the thin bamboo strips: the volume ratio of the thin bamboo strips is selected to be 0.20-0.30%, and the unit consumption of the thin bamboo strips is 1.44kg/m³～2.16kg/m³(ii) a The unit dosage of five samples with the lengths of 5-10 mm, 10-15 mm, 15-20 mm, 20-25 mm and 25-30 mm which are subjected to surface soaking treatment and drained is 1.44kg/m³、1.80kg/m³、2.16kg/m³The bamboo skin wires are respectively mixed with the standard design components in the cement concrete chamber to prepare concrete mixtures, and the workability, segregation, bleeding amount and the dispersibility of the concrete mixtures are tested to determine the length and unit dosage of the bamboo skin wires; (2) determining the unit dosage of the bamboo dust: calculating according to the total volume rate of the bamboo scraps and the thin bamboo strips not more than 0.30%, and determining the volume rate of the bamboo scraps and the single bamboo stripsBit amount; (3) preparing bamboo scraps and thin bamboo strips and surface soaking: preparing materials according to the specifications of selected bamboo scraps and thin bamboo strips, stacking the materials according to classes and specifications in separate bins, soaking the materials in an A latex solution with the mass concentration of 10% for at least 24 hours before use, and draining. Preferably, in order to prevent the bamboo concrete mixture from being easily stirred into a cluster and not dispersed due to the overlong length of the bamboo skin wires and reduce the number of local bamboo skin wires in the bamboo concrete so as to influence various mechanical properties of the bamboo concrete, the length of the selected bamboo skin wires is 15-20 mm, and the unit dosage of the selected bamboo skin wires is 1.80kg/m³The length and unit dosage of the bamboo wood concrete component are designed and used. The total volume rate of the bamboo chips and thin bamboo strips is calculated according to the total volume rate of not more than 0.30 percent, and the unit dosage of the bamboo chips is 0.36kg/m³The volume fraction was 0.05%. The materials are prepared according to the specification of selected bamboo scraps and bamboo skin filaments on the site of a mixing plant, the storage time of the prepared materials is not more than 5 days, the prepared materials are stacked according to the classification and specification by separation bins, and are marked, rain-proof, damp-proof and insect-proof to be kept and managed. In order to prevent the fiber reinforcement and toughening effects of the bamboo scraps and the thin bamboo strips, the bamboo scraps and the thin bamboo strips are not weakened in the process of soaking in the cement paste alkaline solution, and the bamboo scraps and the thin bamboo strips are required to be soaked in the A latex solution with the mass concentration of 10% for 24 hours before use and then drained into a natural drying state for later use.

Further, the trial mixing and quality inspection of the bamboo wood concrete component in the room in the step S3 includes the following steps: (1) the feeding method, the feeding sequence and the stirring time of the components of the bamboo wood concrete are as follows: mixing bamboo chips with sand for at least 60s, adding cement, sand and bamboo chips, mixing for at least 30s, adding broken stone, sand, bamboo chips and cement, mixing for at least 60s, adding bamboo skin silk, sand, bamboo chips, cement and broken stone, mixing for at least 90s, adding a water reducing agent, sand, bamboo chips, cement, broken stone and bamboo skin silk, mixing for at least 60s, and adding mixing water, sand, bamboo chips, cement, broken stone, bamboo skin silk and the water reducing agent, and mixing for at least 180 s; (2) mixing bamboo wood concrete indoors; (3) and (5) quality inspection. The determined feeding method, feeding sequence and stirring time of the components of the bamboo concrete enable bamboo chips and bamboo split filaments to be uniformly dispersed in concrete stirring.

In the bamboo concrete hardening stage, cement and water are mixed to generate a large amount of heat, so that the internal temperature of concrete greatly exceeds the external temperature, larger temperature stress is caused, and cracks are directly generated on the surface of the concrete. However, after the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials are soaked in the A latex solution with the mass concentration of 10% for 24 hours, a layer of compact high-molecular latex protective film is formed on the surface of the A latex solution, so that the contact between the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement and cement is blocked, most of heat is directly contacted with concrete in a large amount of heat generated by mixing the cement and water, and the remaining small amount of residual heat can influence the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials. In addition, the protective film of the polymer latex has the performance of easy heat dissipation, so that the heat dissipation performance of the bamboo concrete is improved, and the generation of cracks is reduced.

According to another aspect of the present invention, there is also provided a method for paving a road surface, comprising the steps of:

s1, preparation including: preparing materials of all the components, inspecting the materials entering a field, and preparing the materials on a construction site;

s2, paving construction, comprising: mixing bamboo concrete, transporting the bamboo concrete, unloading the bamboo concrete, paving the bamboo concrete, vibrating the bamboo concrete, leveling, finely leveling, maintaining, grooving, joint-cutting, joint-filling, preventing water and corrosion, maintaining and inspecting and evaluating the quality of the formed bamboo concrete pavement.

The pavement paving construction method of bamboo concrete provided by the invention has the advantages that in order to realize low-carbon environmental protection and co-construction green ecology and reduce the environment pollution caused by bamboo waste, the residual tailings of the bamboo-woven artware are processed into bamboo chips, bamboo thin bamboo strips, bamboo ribs and bamboo columns, and the bamboo chips, the bamboo thin bamboo strips, the bamboo ribs and the bamboo columns are applied to pavement construction of roads or terraces, so that the advantages of green environmental protection, low price and reinforcement and toughening of natural organic fibers of bamboo are exerted. In the future development trend of building materials, bamboo materials have better development and engineering application prospects. Moreover, the tensile strength of the bamboo is gradually increased from the central layer to the outer skin layer, the bamboo has a gradient tensile characteristic, the tensile strength of the outer skin layer is close to 200MPa, and the bamboo has high tensile strength and toughness. The bamboo has the advantages of light density and low price compared with steel.

Further, the step S1 of preparing the materials of each component includes: preparing bamboo ribs, twisting long bamboo strips with the length of 2000-2500 mm, the width of 5-10 mm and the thickness of 2-3 mm into bamboo ropes with the surfaces in a spiral shape, twisting at least 2 bamboo ropes into bamboo ribs, and arranging knots on the surfaces of the bamboo ribs at intervals. Preparing the bamboo column, namely preparing the bamboo stalks into the bamboo column with the length of 400-500 mm and the width of 20-30 mm. Soaking the surfaces of the bamboo ribs and the bamboo columns for at least 24 hours in an A latex solution with the mass concentration of 10% before use, and draining. In order to improve the tensile strength of the thin bamboo strips, increase the bonding force between the bamboo ribs and concrete and prevent the sliding between the bamboo ribs and the concrete, the thin bamboo strips with the length of 2000-2500 mm, the width of 5-10 mm and the thickness of 2-3 mm are made by stripping and cutting the thin bamboo strips from the bamboo stalks, and the thin bamboo strips on the outer layer in the long strip shape and the bamboo stalks are then twisted to form the bamboo ribs with the spiral surfaces and knots. The twisting method of the bamboo reinforcement comprises the following steps: firstly, 1 thin bamboo strip is twisted into 1 strand of bamboo rope by right twisting or left twisting, then at least 2 strands of bamboo ropes are twisted into bamboo ribs by right twisting or left twisting, and 1 half knot is arranged at the positions of two ends and the middle part of each bamboo rib at intervals of 500 mm. Can be formed by twisting 3 or 4 or 5 or more bamboo ropes. The diameter of the bamboo reinforcement is determined according to the requirement of the engineering part. The bamboo column mainly has the following functions: the double-layer bamboo rib net is positioned and fixedly installed, and the pavement structure base layer and the pavement structure bamboo concrete layer are connected in an anchoring and pulling mode, so that the bonding capacity between the pavement structure base layer and the pavement structure bamboo concrete layer is enhanced. In addition, the tensile strength of bamboo is gradually increased from the central layer to the outer skin layer, so that the tensile strength of the outer skin layer is close to 200.0MPa and is close to that of steel. Therefore, the required tensile strength can be achieved by only increasing the cross-sectional areas of the bamboo columns and the bamboo ribs. The bamboo columns and the bamboo ribs can also replace the reinforcing steel bars. Therefore, in the concrete engineering application process, on one hand, the adhesion among the bamboo skin wires, the bamboo ribs and the concrete needs to be ensured; on the other hand, protection measures such as water resistance, corrosion resistance, reinforcement and toughening function reduction of the bamboo wood are required. Therefore, the strength of the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo ribs can not be reduced or is reduced little in the long-term use process.

In order to prevent the bamboo material from being easily corroded into fibers after being placed for a long time, so that the function failure is caused, and the defects of reinforcement and crack resistance of the bamboo material are reduced. The bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials are processed at any time and used at any time, after the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials are processed, the surfaces of the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials are soaked in time, a layer of compact high-molecular latex protective film is formed on the surface layer of the bamboo chips, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials, the prepared materials are stored in a stirring station on site for no more than 5 days, and the materials are kept in a rainproof, moistureproof and insect corrosion-proof mode. Before entering the field, the bamboo scraps, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials need to be subjected to insect corrosivity inspection, and the bamboo scraps, the thin bamboo strips, the bamboo columns and the bamboo reinforcement materials corroded by rainwater and insects are strictly forbidden to be used.

In this embodiment, the following control method is used for protection: 1. the bamboo skin silk is shaped like a special shape, which is beneficial to bonding with concrete and enhances the bonding force between the bamboo skin silk and the concrete. 2. The outer surface of the bamboo reinforcement is provided with a spiral shape and a knot, and the purpose is to improve the tensile strength of the thin bamboo strips, enhance the bonding force between the bamboo reinforcement and the concrete and prevent the bamboo reinforcement and the concrete from sliding. 3. The method comprises the following steps of soaking bamboo scraps, thin bamboo strips, bamboo columns and bamboo ribs in an A latex solution with the mass concentration of 10% for 24 hours before use, and draining to form natural drying surface treatment, so as to prevent the reduction of the fiber reinforcement and toughening effects of the bamboo scraps, the thin bamboo strips, the bamboo columns and the bamboo ribs. The surfaces of the bamboo scraps, the thin bamboo strips, the bamboo columns and the bamboo ribs are treated, a layer of compact high-molecular latex protective film is formed on the surface layer of the bamboo scraps, the thin bamboo strips, the bamboo columns and the bamboo ribs, the contact between the bamboo scraps, the thin bamboo strips, the bamboo columns and the bamboo ribs and alkaline cement is blocked, and the degradation of bamboo fibers is effectively prevented. 4. The bamboo columns and the bamboo rib nets are provided with concrete protective layers with enough thickness, so that the bamboo columns and the bamboo rib nets are prevented from being corroded by insects and rainwater. 5. And (5) waterproof construction during installation of the bamboo columns. The bamboo column is inserted into the waterproof mortar and is wrapped by the periphery of the waterproof mortar, and the top of the bamboo column is provided with a concrete protective layer with enough thickness, so that the bamboo column is prevented from being corroded by insects and rainwater. 6. The bamboo wood concrete surface layer is provided with a waterproof coating, and the purpose is to prevent the bamboo wood concrete surface layer from being corroded by insects and rainwater. 7. The plastic film of the bamboo concrete covers the early maintenance, and aims to prevent the bamboo concrete from being corroded by insects and rainwater in the early stage. 8. The waterproof and anti-corrosion construction of the joint filling layer prevents surface water of the pavement structure surface layer from permeating into a construction joint or an expansion joint or a contraction joint, soaks bamboo chips, bamboo strips, bamboo columns and bamboo ribs, is corroded by insects and rainwater, reduces the filling compactness of the bamboo chips, and reduces the mechanical properties of the bamboo strips, the bamboo columns and the bamboo ribs.

Further, the job site preparation in step S1 includes: and (2) mounting the bamboo columns, drilling holes at the designed positions (the longitudinal and transverse spacing of the bamboo columns is 1000mm multiplied by 500mm) of the bamboo columns on the top surface of the pavement structure base layer to obtain blind holes, filling the blind holes with waterproof mortar, inserting the bamboo columns into the blind holes, and waiting for the waterproof mortar to be condensed. And (3) installing the bamboo rib net, wherein the bamboo rib net is positioned at the lower part of the bamboo column, the bamboo ribs are sequentially wound around each bamboo column for one circle along the horizontal length direction to form warp-direction bamboo ribs, the bamboo ribs are woven in a staggered mode with the warp-direction bamboo ribs one above another along the horizontal width direction to form a bottom layer bamboo rib net, the bamboo rib net is positioned at the upper part of the bamboo column, and the top layer bamboo rib net is formed by adopting the same method as the bottom layer bamboo rib net. The distance between the top end of the bamboo column and the top layer bamboo rib net is 20-30 mm. The distance from the bottom layer bamboo rib net to the top surface of the base layer of the pavement structure is more than or equal to 100 mm. The design position of the bamboo columns (the bamboo columns are arranged at the vertical and horizontal intervals and are designed to be 1000mm multiplied by 500mm) on the top surface of the pavement structure base layer is drilled with a percussion drill to obtain round holes with the diameter of 50mm and the depth of 150mm, stone residues in the holes are taken out, and dust in the holes is blown clean. And (2) pouring waterproof mortar into the round hole to the top surface of the hole, wherein the mixing ratio of the waterproof mortar to cement to sand to water to a waterproof agent is 1: 3: 3.25: 0.05 (mass ratio), vertically inserting the bamboo columns which are soaked on the surfaces and drained into the hole for 120mm of depth, and repeatedly inserting the bamboo columns into the hole for 3-5 times from top to bottom, so that the waterproof mortar overflows the top surface of the hole, and the waterproof mortar is guaranteed to be tightly filled with the bamboo columns and the hole wall pores in the hole. And after the waterproof mortar is finally set, the bamboo reinforcement net can be installed. And after the top layer bamboo rib net is installed, cutting off the redundant part of the height of the bamboo column, so that the height of the installed bamboo column is 20-30 mm higher than that of the top layer bamboo rib net. And sequentially winding the bamboo reinforcement around each bamboo column for one circle along the horizontal length direction to form a warp-wise bamboo reinforcement, and weaving the bamboo reinforcement and the warp-wise bamboo reinforcement in a staggered manner along the horizontal width direction one above the other to form a bottom layer bamboo reinforcement net. The bamboo ropes are adopted to bind the crossed nodes of the bamboo rib grids firmly, the binding is performed by adopting an 8-shaped mode of changing the direction of the bamboo ropes point by point and staggered binding or a cross mode of double diagonal lines, and the side length of the grids is 200 mm. And (4) finishing the installation of the top layer bamboo rib net by adopting the same method at the installation design position of the top layer bamboo rib net. The two bamboo ribs are connected by a knot method, and the connection needs to be firm and not to loosen. The pavement structure layer comprises a pavement structure base layer and a pavement structure surface layer positioned on the upper part of the pavement structure base layer. The pavement structure surface layer comprises bamboo columns, bamboo rib nets, bamboo concrete and joint filling layers. The distance between the bottom layer bamboo rib net and the top surface of the base layer of the pavement structure is more than or equal to 100 mm. The distance between the bottom layer bamboo rib net, the distance between the top layer bamboo rib net and the gap filling layer are all kept to be larger than or equal to 100mm, so that the bamboo rib net is favorable for a concrete protective layer with enough thickness to avoid the corrosion of wetting by insects and rainwater. Keep more than or equal to 150mm distance between top layer bamboo muscle net and the road surface structure surface course top surface, when preventing road surface structure surface course shrinkage joint cutting, the cutting is disconnected level and is to the bamboo muscle, influences the atress of bamboo post and bamboo muscle net. The erection height between the bottom layer bamboo rib net and the top layer bamboo rib net is determined by deducting the thickness of the upper and lower concrete protective layers of the bamboo rib net according to the thickness of the pavement structural surface slab. After the top layer bamboo rib net is installed, cutting off the redundant part of the height of the bamboo column, enabling the height of the installed bamboo column to be 20-30 mm higher than that of the top layer bamboo rib net, and enabling the bamboo column to be free from corrosion caused by wetting of insects and rainwater due to the fact that a concrete protective layer of 120-130 mm is arranged on the top surface of the pavement structure surface layer. Through set up double-deck formula bamboo muscle net of weaving at road surface structure bamboo timber concrete layer, improve the whole bearing capacity of road surface structure bamboo timber concrete layer, avoid receiving the brittle fracture problem of taking place behind the vehicle-mounted load. Through set up heliciform and knot bamboo muscle at road surface structure bamboo timber concrete layer, increase the cohesive force between bamboo muscle and concrete, prevent to slide between bamboo muscle and concrete, improve road surface structure bamboo timber concrete layer's bending tensile strength.

As shown in fig. 2, the paving construction of step S2 further includes: (1) paving construction verification, outside a paving construction area of a bamboo wood concrete pavement on a construction site, selecting an easy-settlement and unstable section of a embankment and cutting transition section with the length of no less than 100m and the width of 3.5m, a half-filled and half-dug embankment or a soft soil foundation for treating the embankment or a high embankment with the maximum filled soil slope height of more than 20m for paving construction verification, wherein the verification content comprises the following steps: and determining the mixing parameters, the actual production capacity and the batching precision of a mixing plant of the mixing station. And (5) inspecting the construction performance and technical parameters of the concrete. And (5) checking the paving machinery, process parameters and the matching condition with the mixing capability. Actually measuring the temperature of the bamboo wood concrete pavement paving construction site, and determining the component design components of the bamboo wood concrete pavement used by the temperature. And actually measuring the finish time of the concrete surface finish surface after the bamboo wood concrete mixture is discharged to the paving construction site, and verifying whether the initial setting time and the final setting time of the concrete of the indoor design components of the bamboo wood concrete meet the paving construction requirements of the construction site. Actually measuring slump, segregation, bleeding quantity, bamboo chip and bamboo strip filament dispersibility, bamboo chip and bamboo strip filament volume ratio, loose paving coefficient, paving speed, vibration time and frequency, bending strength, splitting strength and durability (early crack resistance and abrasion loss) of the bamboo concrete. And actually measuring the anti-skid structure depth and the friction coefficient of the bamboo concrete pavement concrete. And (3) actually measuring the bubble spacing coefficient of the bamboo concrete pavement concrete by drilling a core sample, checking the size and uniformity of bubbles and the compactness of the bamboo concrete pavement concrete, and verifying the adaptability of the bamboo concrete pavement component design components and the concrete vibrator paved on a construction site. (2) And summarizing the paving construction, namely after the quality of the bamboo wood concrete pavement is checked, accepted and evaluated, summarizing the component design of the bamboo wood concrete pavement and the paving construction verification thereof in time, and providing construction guidance for the later formal paving construction of the bamboo wood concrete pavement. (3) And (3) formal paving construction, namely paving the bamboo concrete pavement of the road or the terrace pavement according to the technical parameters summarized by the paving construction verification steps and the paving construction.

Preferably, the length of the second-level highway pavement in the selected mountain area is not less than 100m, the width of the second-level highway pavement is 7.0m, construction is performed in a left half and a right half, and paving construction verification is performed with each half being 3.50 m.

The invention has the following beneficial effects:

the bamboo concrete of the invention comprises: cement, sand, broken stone, bamboo chips, bamboo strips, water and a water reducing agent. The concrete is prepared by mixing cement, sand, broken stone and water, bamboo chips are added into the concrete to improve the grading of sand particles and fill the gaps between the sand particles, the bamboo chips are mixed with the sand, the cement and the water to form composite slurry, the gaps between the broken stone in the concrete are filled and compacted to improve the compressive strength of the concrete, the defect that the compressive strength of the concrete is slightly reduced after the bamboo fibers are added into the concrete is overcome, and the compressive strength of the concrete meets the engineering use requirements. Simultaneously, make the total surface area increase of concrete aggregate, and then increase the air content in the concrete, tiny bubble plays the ball effect in the concrete, makes concrete slump obtain improving, and the cohesion of the bubble of increase still can make the concrete increase. Moreover, the air bubbles are adhered with the solid particles, so that the solid particle sinking and water flowing are reduced, a bleeding channel is blocked, the bleeding quantity of the concrete is reduced, and the segregation of the concrete is improved. The bamboo split wires and the concrete have stronger binding power, so that the ductility and the bending resistance of the concrete are obviously improved, and the expansion of concrete cracks adjacent to the bamboo split wires is prevented. Meanwhile, due to the three-dimensional disorderly distribution of the bamboo chips and the bamboo skin, the plastic shrinkage of the concrete is weakened, shrinkage cracks and cracks in the initial setting of the concrete are reduced, the early-stage crack resistance of the concrete is improved, the abrasion loss of the concrete is reduced, the durability of the concrete is improved, and the service life of the bamboo concrete is prolonged. In addition, because added bamboo bits, thin bamboo strips used for weaving silk in the concrete, in order to satisfy the workability of bamboo timber concrete, need increase in the concrete with the water yield, increase concrete water-cement ratio, lead to concrete compressive strength, bending tensile strength to reduce, add the water-reducing agent in the concrete, can reduce in the concrete with the water yield, reduce concrete water-cement ratio, strengthen concrete compressive strength, bending tensile strength, can also increase the mobility of concrete. The slump of the concrete is reduced or increased by reducing or increasing the mass mixing amount of the water reducing agent in the concrete so as to meet the requirement of pavement construction of the pavement concrete at the temperature of 5-35 ℃. The bamboo concrete solves the problems of low bending tensile strength, brittleness, easy fracture, poor durability and short service life of a cement concrete pavement, avoids the problems of high production cost of steel fiber concrete and poor temperature stability of asphalt concrete due to asphalt materials, and has the advantages of recycling bamboo materials with low price, energy conservation, environmental protection, reinforcement and toughening, protecting resource environment, reducing pollution of wastes, reducing the construction cost of a road or a terrace pavement, along with simple and convenient construction process operation and convenient wide application.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic flow diagram of a method for preparing bamboo concrete according to the present invention;

fig. 2 is a schematic flow chart of the bamboo concrete pavement paving construction method of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The preparation method of the bamboo concrete comprises the following steps:

according to the requirements specified in the highway cement concrete pavement construction technical Specification (JTG/T F30-2014), the construction of bamboo wood concrete pavements of certain grade roads in Guangxi, which is designed to have the bending tensile strength of 4.5MPa, and has the medium traffic load grade of the spreading construction of a self-discharging transport vehicle and a three-roller-shaft unit, is taken as an example for detailed description. Before designing components of a bamboo concrete pavement, the following preparation work at the early stage is needed:

(1) and investigating the specification, model, quality and storage capacity of local cement, sand, gravel and water reducing agent according to the design of engineering construction drawings and the requirements of construction tasks.

(2) And in order to co-establish green ecology, practice low carbon and environmental protection and reduce the environmental pollution caused by wastes, the residual tailings of the bamboo-woven artware are recycled in the concrete pavement. The quality and the storage capacity of the bamboo waste materials of local bamboo ware product factories are investigated, the bamboo waste materials are sorted, washed with water to remove impurities, and processed into bamboo scraps and thin bamboo strips required by concrete pavements and bamboo ribs and bamboo columns required by pavement structure layer construction.

(3) Processing bamboo scraps, thin bamboo strips, bamboo ribs and bamboo columns, wherein the granularity of the bamboo scraps is 30 meshes (the size of a square hole sieve is 0.600 mm); the lengths of the thin bamboo strips are respectively processed into five samples of 5-10 mm, 10-15 mm, 15-20 mm, 20-25 mm and 25-30 mm for the component design test and the selection of the concrete pavement. The bamboo reinforcement is made by stripping and cutting bamboo chips from bamboo stalks to form long-strip-shaped middle and outer layer thin bamboo strips with the length of 2000-2500 mm, the width of 5-10 mm and the thickness of 2-3 mm, and then the strips are processed and twisted to form a strip with a spiral surface and knots. The bamboo column is split from Ci bamboo stalk into long bamboo strips with the length of 400-500 mm, the width of 20-30 mm and the thickness of bamboo stalk.

(4) The surface soaking treatment of bamboo scraps, thin bamboo strips, bamboo ribs and bamboo columns is to prevent the fiber reinforcing and toughening effects of the bamboo scraps, the thin bamboo strips, the bamboo ribs and the bamboo columns from being weakened in the soaking of cement slurry alkaline solution, and before the use, the bamboo scraps, the thin bamboo strips, the bamboo ribs and the bamboo columns are required to be soaked in 10% A latex solution for 24 hours and then drained into a natural drying state for later use.

S1 inspection of bamboo-wood concrete composition material

The bamboo concrete is a mixture prepared by mixing cement, sand, broken stone, bamboo chips, bamboo strips, a high-efficiency water reducing agent and mixing water according to a certain proportion.

According to the determined type and specification of the bamboo concrete composition materials, the preparation of each composition material on site of the mixing plant is carried out, the storage time of the prepared materials is not more than 5 days, the materials are stacked according to classification and specification by compartment, and are marked, rain-proof, damp-proof and insect-proof to be kept and managed. Before entering the field, the cement, sand, gravel, bamboo chips, bamboo strips, a high-efficiency water reducing agent and mixing water are subjected to relevant quality index inspection, and all inspection results can be used after meeting the requirements of national and industry relevant construction technical specifications, product standards or technical documents. Before entering the field, the bamboo scraps and thin bamboo strips and wires are subjected to insect corrosivity inspection, and the bamboo scraps and thin bamboo strips and wires corroded by rainwater and insects are strictly forbidden to be used.

S101, cement: the red lion brand P.O42.5 ordinary portland cement is adopted, and the inspection result is as follows: specific surface area is 338m²The initial setting time is 186min, the final setting time is 249min, the stability is qualified, the compressive strength is 48.6MPa in 28 days, the flexural strength is 8.2MPa in 28 days, and all the inspection indexes meet the technical requirement of P.O42.5 in the Standard of Portland Cement Universal (GB 175).

S102, sand: adopting river sand with hard texture, durability and cleanness, and testing and checking results: fineness modulus of 2.6, grain composition of zone II, mud content (by mass) of 1.5%, mud cake content (by mass) of 0.2%, chloride ion content (by mass) of 0.002%, and sulfide and sulfate content (by mass SO)₃By mass) of 0.18%, a water absorption of 1.1%, and an apparent density of 2620kg/m³The loose bulk density is 1490kg/m³The tap density is 1660kg/m³The void ratio is 43 percent, the rapid alkali-silicic acid reaction (14d expansion ratio) is 0.06 percent, no potential alkali-silicic acid reaction hazard exists, and the quality of the product meets the technical requirements of grade III sand in the highway cement concrete pavement construction technical rules (JTG/TF 30-2014).

S103, crushing stones: hard, durable and clean limestone is crushed and processed into single-particle-grade crushed stone with the particle size of 4.75-9.5 mm and the particle size of 9.5-19 mm. Test and inspection results: the rock water-saturated compressive strength is 125.8MPa, the rapid alkali-silicic acid reaction (14d expansion rate) is 0.08 percent, the potential alkali-silicic acid reaction hazard is avoided, and the quality of the rock meets the technical requirements of road cement concrete pavement construction technical rules (JTG/TF30-2014) standard macadam.

S104, bamboo dust: adopts natural organic fiber with clean outer surface, green and environment-friendly Sagittaria sagittifolia with bamboo stalk fiber toughness for more than 3 years. Bamboo scraps are formed by sawdust on Ci bamboo stalks, the granularity of the bamboo scraps is 30 meshes, the bamboo scraps are soaked in an A latex solution with the mass concentration of 10% for 24 hours before use, and then the bamboo scraps are drained to be in a natural dry state for standby. The bamboo chips improve the grading of sand particles and fill the gaps of the frameworks between the sands, the bamboo chips are mixed with the sands, the cement and the water to form composite slurry, the gaps between the broken stones in the concrete are filled and compacted to improve the compressive strength of the concrete, the defect that the compressive strength of the concrete is slightly reduced after the bamboo fibers are added into the concrete is overcome, and the compressive strength of the concrete meets the engineering use requirements. Simultaneously, make the increase of concrete aggregate total surface area and then increase the air content in the concrete, tiny bubble plays the ball effect in the concrete, makes concrete slump obtain improving, and the increase bubble can also make the cohesion of concrete increase, and the bubble bonds solid particle, reduces solid particle and sinks and rivers flow, blocks the bleeding passageway, reduces the concrete bleeding volume, improves the concrete segregation.

S105, thin bamboo strips: the bamboo is stripped and cut from a bamboo stalk into bamboo chips with natural organic fibers with clean outer surfaces, green and environment-friendly bamboo with strong bamboo stalk fiber toughness for more than 3 years, and the bamboo chips are made into a mixed shape of one or more of a strip shape, a trapezoid shape, a needle point shape, an arrow tail shape and an oval shape, wherein the length of the strip shape, the trapezoid shape, the needle point shape, the arrow tail shape and the oval shape are 15-20 mm, the width of the strip shape is 2.0-3.0 mm and the thickness of the strip shape is 1.0-1.5 mm. And adopts the bamboo skin silk on the outer layer in the bamboo stalk. Before use, the latex is soaked in an A latex solution with the mass concentration of 10% for 24 hours, and then drained to be in a natural dry state for later use. The specially-shaped bamboo skin wires have strong bonding force with concrete, so that the ductility and the bending resistance of the concrete are obviously improved, and the expansion of concrete cracks adjacent to the bamboo skin wires is prevented. Meanwhile, due to the three-dimensional disorderly distribution of the bamboo chips and the bamboo skin, the plastic shrinkage of the concrete is weakened, shrinkage cracks and cracks in the initial setting of the concrete are reduced, the early-stage crack resistance of the concrete is improved, the abrasion loss of the concrete is reduced, the durability of the concrete is improved, and the service life of the bamboo concrete is prolonged.

S106, water reducing agent: the BX-II type retarding superplasticizer is adopted, powder is adopted, the water reducing rate is 22%, the mass mixing amount is 1.2% of the mass of cement, and the mass of the powder meets the technical requirements of the retarding superplasticizer in the standard of concrete admixture (GB 8076).

S107, mixing water: the drinking water meeting the national standard is selected.

S2 design of cement concrete indoor reference components

S201: samples of the constituent materials were prepared. And (3) extracting enough sand, crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm from a mixing station on-site material preparation warehouse, and air-drying and airing the samples to keep the sand and the crushed stone in a saturated surface dry state. Before designing the cement concrete reference components, extracting sufficient quantities of cement and a high-efficiency water reducing agent from a mixing station on-site material preparation warehouse, drying aired sand, crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm by air, mixing water, putting the mixture into a concrete component design room in advance for 1 day, and controlling the indoor temperature within the range of 20 +/-5 ℃.

S202: mixing and synthesizing broken stones and inspecting quality.

1. Mixing and synthesizing the crushed stones. In order to ensure the stability of the crushed stone grading, the crushed stones with the granularity of 4.75-9.5 mm and the crushed stones with the granularity of 9.5-19 mm in the saturated surface dry state are mixed into 30kg respectively according to four proportions of 62 percent, 38 percent, 52 percent, 48 percent, 42 percent, 58 percent and 32 percent, 68 percent in percentage by mass, and then the screening test detection is respectively carried out. The synthetic grading after blending the four proportions is shown in Table 1.

TABLE 1 Synthesis grading of the four proportions

(1) The detection results of the screening tests of the first to fourth groups are as follows: firstly, the crushed stone gradation synthesized by blending the group proportion is out of the synthetic gradation range of 4.75-19 mm due to the fact that the content of particles with the particle size of more than 9.50mm is low; secondly, the grading of the crushed stone synthesized by blending the group proportion is in the range of 4.75-19 mm synthetic grading; thirdly, the grading of the crushed stone synthesized by blending the group proportions is in the range of 4.75-19 mm synthetic grading; and fourthly, the crushed stone gradation synthesized by blending the components according to the proportion is out of the synthetic gradation range of 4.75-19 mm due to the fact that the content of particles with the particle size of more than 9.50mm is relatively large.

(2) The screening test results of the groups I to IV can be obtained: the blending proportion of the synthetic graded crushed stone which conforms to 4.75-19 mm can fluctuate within the range of 42-52 percent to 58-48 percent.

Through four groups of screening tests, the reasonable fluctuation blending proportion range of the synthetic graded broken stone can be obtained, the quality control of the broken stone blending synthesis when concrete is mixed on site is facilitated, and the stability of the site broken stone grading is ensured.

(3) The crushed stone with the granularity of 4.75-9.5 mm and the crushed stone with the granularity of 9.5-19 mm are blended according to the mass percentage of 47% to 53% to obtain the synthetic graded crushed stone with the granularity of 4.75-19 mm, wherein the median values of the upper limit value and the lower limit value of the reasonable fluctuation blending ratio are respectively taken as the mixing ratio.

2. And (5) quality inspection. Mixing crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm in a saturated surface dry state according to the mass percent of 47% to 53% to form synthetic graded crushed stone with the mass of 4.75-19 mm, and screening, and carrying out test detection on the mud content, the mud block content, the water absorption rate, the sulfide and sulfate content, the needle-shaped particle content, the crushing value, the apparent density, the loose bulk density, the tap density and the void ratio. The test detection result is as follows: in the gradation range, the content of sludge (by mass) was 0.6%, the content of clod (by mass) was 0.1%, the water absorption (by mass) was 1.3%, and the contents of sulfide and sulfate (by SO)₃By mass) of 0.18 percent, the content (by mass) of needle-like and flaky particles of 11.2 percent, the crushing value of 19.6 percent and the apparent density of 2720kg/m³The loose bulk density is 1520kg/m³The tap density is 1700kg/m³The void ratio is 44 percent, and the quality of the concrete meets the technical requirement of grade III macadam in the Standard of Highway Cement concrete pavement construction technical rules (JTG/TF 30-2014).

S203, designing and calculating cement concrete components

S2031, preparing 28d flexural tensile strength average value, slump, water-cement ratio, sand rate, unit water consumption, unit cement consumption, water reducer consumption, sand consumption and gravel consumption for surface cement concrete, and calculating by an empirical formula method of item 4.2.11 of design of the mix proportion of the cement concrete in chapter 4.2 in the detail rules of Highway Cement concrete pavement construction technology (JTG/TF 30-2014). The calculation is as follows:

1. the average bending and tensile strength of the surface cement concrete prepared for 28d is 5.42MPa according to the formula (4.2.2) in the 4.2.2 standard of the detail rules of road cement concrete pavement construction technology (JTG/T F30-2014).

2. Slump according to the three-roller-shaft unit paving construction process in the 4.2.3 th Standard of detail rules of Highway Cement concrete pavement construction technology (JTG/TF30-2014), the site slump of the mixture is 20-40 mm, the slump loss value of the concrete mixture in the transportation process is 30mm, the slump of a discharge port of a concrete mixture stirring station is 50-70 mm, and the slump is selected as follows: 70 mm.

3. The water-cement ratio is calculated according to the formula (4.2.11-1) in item 4.2.11 of Standard of Highway Cement concrete pavement construction technical rules (JTG/TF 30-2014): W/C is 0.45, which is less than the standard 4.2.4 table 4.2.4, which specifies a second maximum water-cement ratio of 0.46 for a road grade, the water-cement ratio is selected to be 0.45.

4. The sand rate is as per item 4.2.11-1 of standard JTG/TF30-2014 of Highway concrete pavement construction technical rules, the fineness modulus of sand is 2.6, and the selection of the broken stone table look-up is 34%.

5. The unit water consumption is 172.38kg/m calculated according to the formula (4.2.11-3) of the Standard 4.2.11 of the rules of construction technology for Cement concrete road pavement (JTG/TF30-2014) and according to the fact that the crushed stone and the slump are 70mm³Is larger than the Standard of Highway Cement concrete pavement construction technical rules (JTG/TF30-2014) 4.2.11, Table 4.2.11-2 maximum unit water consumption of three-roller shaft machine set for paving broken stone concrete 153kg/m³The specification of (1). The unit water consumption of the concrete is reduced to 134.46kg/m by doping the retarding superplasticizer with the water reducing rate of 22 percent³Is less than the Standard of Fine rules of Highway Cement concrete pavement construction technology (JTG/TF30-2014) Standard 4.2.11, Table 4.2.11-2 maximum Unit Water consumption of 153kg/m for paving broken stone concrete by a three-roller-shaft machine set³The specification of (1). The unit water consumption is 134kg/m³。

6. The unit cement dosage is calculated according to the formula (4.2.11-6) in the Specification for Highway Cement concrete pavement construction technology (JTG/TF30-2014) standard: 297.78kg/m³Is less than the standard4.2.4 in Table 4.2.4 (cement 42.5 grade, highway grade two grade) the minimum unit cement dosage is 310kg/m³The unit cement dosage is 310kg/m³。

7. The dosage of the water reducing agent is that the water reducing agent adopts BX-II type retarding superplasticizer and powder, the mass mixing amount of the powder is 1.2 percent of the mass of the cement, and the calculation is as follows: 3.72kg/m³。

8. The sand dosage and the broken stone dosage are calculated by a mass method, and the unit mass of the concrete is assumed to be 2400kg/m³. Then: the sand amount and the gravel amount can be calculated according to the formulas (5.5.1-1) and (5.5.1-2) in the standard No. 5.5.1 (quality method) of the design rule of the mix proportion of common concrete (JGJ 55-2011): the amount of sand used is 664kg/m³The dosage of the crushed stone is 1288kg/m³。

9. The crushed stone is 4.75-19 mm synthetic graded crushed stone, and is prepared by mixing crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm according to the mass percentage of 47% to 53%, so that the crushed stone with the granularity of 4.75-9.5 mm is used in 605kg/m³683kg/m of broken stone with the granularity of 9.5-19 mm³。

10. And checking and calculating the filling volume rate of the crushed stones. And (4) carrying out checking calculation on the filling volume rate of the crushed stones on the concrete component obtained by calculation so as to better ensure the formation of a compact structure of the internal framework of the concrete. The filling volume ratio (%) of crushed stone is (crushed stone amount/tap density) × 100% (1288/1700) × 100% > (75.76%), which meets the regulation of "the filling volume ratio of coarse aggregate is not less than 70%" in article 7 of the standard JTG/TF30-2014 in the technical and technical rules of road cement concrete pavement construction.

S2032, determining the calculation components of the cement concrete. The cement concrete comprises the following components of cement, sand, crushed stone with the granularity of 4.75-9.5 mm, crushed stone with the granularity of 9.5-19 mm, water and water reducing agent in a mass ratio of 310, 664, 605, 683, 134, 3.72 (unit: kg/m)³) The water-cement ratio is 0.43, which is less than the standard JTG/TF30-2014 in Standard 4.2.4, the specification of the maximum water-cement ratio 0.46 with the road grade of the second level in Table 4.2.4 meets the requirement.

S204, trial mixing and quality inspection of cement concrete components in room

Indoor trial mixing and quality inspection are carried out on the basis of the calculation components of the cement concrete:

s2041, indoor trial mixing of cement concrete components

1. The amount of the trial-mix material. In a concrete component design room with the indoor temperature of 20 +/-5 ℃, the components are mixed with 40L of concrete mixture according to the calculation of cement concrete, and the following materials are weighed by a 150kg electronic balance with the sensing quantity of 1 g: 12.400kg of cement, 26.560kg of sand, 24.200kg of gravel with the granularity of 4.75-9.5 mm, 27.320kg of gravel with the granularity of 9.5-19 mm, 5.360kg of water and 149g of water reducing agent are weighed.

2. Workability and apparent density are actually measured. Actually measuring slump of the concrete mixture, wherein the actually measured values are 62mm, 65mm and 68mm, the average value is 65mm, and the slump meets the requirement of 50-70 mm slump design; the change of the slump constant of 1h with time is 25 mm; the apparent density was found to be 2390kg/m³Calculating according to the standard No. 6.2.3 of the design rule of the mix proportion of common concrete (JGJ 55-2011): (the measured value of the apparent density of the concrete mixture-the calculated value of the apparent density)/the calculated value of the apparent density is 0.41 percent and less than 2 percent; the concrete mixture has good cohesiveness and water retention, meets the requirement of construction workability, and does not need to correct the calculation components of the cement concrete.

3. According to the slump of the concrete mixture and the actual measurement results of 1h time change, cohesiveness and water retention of the concrete mixture, the concrete mixture can obtain: the cement concrete trial-mix component B comprises cement, sand, crushed stone with the granularity of 4.75-9.5 mm, crushed stone with the granularity of 9.5-19 mm, water and a water reducing agent in a mass ratio of 310: 664: 605: 683: 134: 3.72 (unit: kg/m)³) The water-cement ratio was 0.43 and the sand ratio was 34%.

4. On the basis that the water cement ratio of the cement concrete trial-mix component B group is 0.43, the water cement ratios are 0.38 and 0.48 respectively, the water consumption is not changed, and the cement concrete components of the other A group and the C group are obtained by calculation (by a mass method):

the group A cement concrete comprises cement, sand, crushed stone with the granularity of 4.75-9.5 mm, crushed stone with the granularity of 9.5-19 mm, water and a water reducing agent in a mass ratio of 353: 630: 601: 678: 134: 4.24 (unit: kg/m)³) The water-cement ratio is 0.38, and the sand rate is 33%;

the group C cement concrete comprises cement, sand, crushed stone with the granularity of 4.75-9.5 mm, crushed stone with the granularity of 9.5-19 mm, water and a water reducing agent in a mass ratio of 279: 694: 606: 684: 134: 3.35 (unit: kg/m)³) The water-cement ratio is 0.48, and the sand rate is 35%.

S2042, quality inspection

Respectively calculating, weighing and mixing three groups of cement concrete components with water cement ratios of 0.38, 0.43 and 0.48 to prepare 450L of concrete mixture, and finishing: the apparent density, slump, 1h change with time, cohesiveness, water retention, air content, setting time, segregation, tensile strength, split strength, durability (early crack resistance, abrasion loss) indexes are tested, and the test results are shown in tables 2-1/2-2.

TABLE 2-1 Water cement ratio of 0.38, 0.43, 0.48 three groups of cement concrete component test results (1)

TABLE 2-2 Water cement ratio of 0.38, 0.43, 0.48 three groups of cement concrete component test results (2)

S205, determining the design components of the cement concrete indoor reference

1. And carrying out comparative analysis according to test detection results and economical efficiency of three groups of cement concrete components with water cement ratios of 0.38, 0.43 and 0.48, and determining a component design component with the water cement ratio of 0.43 as a cement concrete indoor reference design component.

2. Indoor standard design component of cement concrete, cementThe mass ratio of the sand, the crushed stone with the granularity of 4.75-9.5 mm, the crushed stone with the granularity of 9.5-19 mm, the water and the water reducing agent is 310, 664, 605, 683, 134, 3.72 (unit: kg/m)³) The water-cement ratio was 0.43 and the sand ratio was 34%.

S3 bamboo wood concrete indoor design component

S301, preparation of bamboo chip and bamboo strip sample

Before the components of the bamboo concrete are designed, a sufficient amount of bamboo chips and bamboo splits which are subjected to surface soaking treatment and are drained are extracted from a mixing station on-site material preparation warehouse and are put into a concrete component design room 1 day in advance, the indoor temperature is required to be consistent with the indoor temperature (namely 20 +/-5 ℃) when the cement concrete is designed indoors based on the standard, and the following preparation work is made.

S3011, determining the length and unit dosage of thin bamboo strips

1. When the components of the bamboo concrete pavement are designed, the fiber volume ratio of the pavement in a 5.3.4-strip table 5.3.4 in the specification of fiber concrete application technical Specification (JGJ/T221-2010) is 0.10-0.30%. The volume ratio of the thin bamboo strips is 0.20-0.30%, and the Sasa albo-marginata density is 720kg/m³The unit dosage of the thin bamboo strips is 1.44-2.16 kg/m³。

2. The unit dosage of five samples with the lengths of 5-10 mm, 10-15 mm, 15-20 mm, 20-25 mm and 25-30 mm which are subjected to surface soaking treatment and drained is 1.44kg/m³、1.80kg/m³、2.16kg/m³The bamboo split filaments are respectively mixed with the indoor standard design components of the cement concrete to prepare 40L concrete mixture. Adding the bamboo skin wires, sand, cement and gravel to mix for 90s, adding the water reducing agent, the sand, the cement, the gravel and the bamboo skin wires to mix for 60s, adding mixing water, the sand, the cement, the gravel, the bamboo skin wires and the water reducing agent to mix for 180s, finally unloading the concrete mixture into a concrete iron plate, and inspecting the workability (slump, stick degree, cohesiveness and water retention property), segregation, bleeding and the dispersibility of the bamboo skin wires of the concrete mixture. The test results are shown in Table 3.

TABLE 3 slump, stick, cohesiveness, water retention, segregation, bleeding and bamboo skin wire dispersibility test results of concrete mixtures

3. Comprehensively analyzing the workability, segregation, bleeding and the dispersion of the concrete mixture according to the specification of the 4.1.1 th strip in the standard of fiber concrete application technical Specification (JGJ/T221-2010) and the test and inspection results in Table 3, selecting the bamboo skin wires with the length of 15-20 mm and the unit dosage of 1.80kg/m³The length and unit dosage of the bamboo wood concrete component are designed and used.

The length of the thin bamboo strips is controlled according to the maximum particle size of the broken stone, so that the condition that the bamboo concrete mixture is easy to stir into lumps and is not dispersed due to the overlong length of the thin bamboo strips is prevented, the quantity of the local thin bamboo strips in the bamboo concrete is small, and various mechanical properties of the bamboo concrete are influenced.

S3012, determining unit dosage of bamboo dust

According to the specification of 0.10-0.30% of the fiber volume ratio of the road pavement in the 5.3.4 bar 5.3.4 of the standard of the fiber concrete application technical Specification (JGJ/T221-2010). The total volume ratio of the bamboo scraps and the thin bamboo strips is not more than 0.30%, so that the unit consumption of the bamboo scraps is 0.36kg/m³The volume fraction was 0.05%.

S3013, preparing bamboo chips and bamboo split threads and performing surface soaking treatment

The materials are prepared according to the specification of selected bamboo scraps and bamboo skin filaments on the site of a mixing plant, the storage time of the prepared materials is not more than 5 days, the prepared materials are stacked according to the classification and specification by separation bins, and are marked, rain-proof, damp-proof and insect-proof to be kept and managed. In order to prevent the fiber reinforcement and toughening effects of the bamboo scraps and the thin bamboo strips, the bamboo scraps and the thin bamboo strips are not weakened in the process of soaking in the cement paste alkaline solution, and the bamboo scraps and the thin bamboo strips are required to be soaked in the A latex solution with the mass concentration of 10% for 24 hours before use and then drained into a natural drying state for later use.

S302, designing and calculating bamboo concrete components

S3021 adjusting design components of cement concrete indoor standard

1. And (4) adjusting components.Because bamboo chips and bamboo skin threads are doped in the bamboo concrete, in order to meet the workability of the bamboo concrete, on the basis of designing components based on the indoor standard of cement concrete, the water-cement ratio is unchanged, the cement slurry consumption is increased by 10 percent and the sand rate is adjusted by 2 percent, namely the cement consumption is increased to 310kg/m³×(1+10％)＝341kg/m³The minimum cementing material dosage is 340kg/m when the maximum water-gel ratio in the 5.1.3 table 5.1.3 of the standard of technical Specification for fiber concrete application (JGJ/T221-³The provision of (1); the water consumption is increased to 134kg/m³×(1+10％)＝147.4kg/m³Is less than the Standard of Fine rules of construction technology for Cement concrete road pavement on Highway (JTG/T F30-2014) Standard 4.2.11, Table 4.2.11-2 maximum Unit Water consumption of 153kg/m for paving broken stone concrete by a three-roller shaft machine set³The water dosage is 147kg/m³(ii) a The sand rate increased to 36%.

2. And (4) adjusting the indoor standard design components of the cement concrete. The cement concrete comprises the following components of cement, sand, crushed stone with the granularity of 4.75-9.5 mm, crushed stone with the granularity of 9.5-19 mm, water and water reducing agent in a mass ratio of 341: 687: 574: 647: 147: 4.09 (unit: kg/m)³) The water-cement ratio was 0.43 and the sand ratio was 36%.

3. And checking and calculating the filling volume rate of the crushed stones. And carrying out checking calculation on the gravel filling volume ratio of the adjusted cement concrete indoor reference design components to better ensure the formation of a concrete internal framework compact structure. The filling volume ratio (%) of crushed stone is (crushed stone amount/tap density) × 100% (1221/1700) × 100% > (71.82%), which meets the regulation of "the filling volume ratio of coarse aggregate is not less than 70%" in article 7 of the standard JTG/T F30-2014 "standards of highway cement concrete pavement construction technology rules (JTG/T F30-2014).

S3022, determining calculation components of bamboo concrete

The bamboo concrete comprises cement, sand, broken stone with the granularity of 4.75-9.5 mm, broken stone with the granularity of 9.5-19 mm, bamboo chips, bamboo thin bamboo strips, water and a water reducing agent in a mass ratio of 341: 687: 574: 647: 0.36: 1.80: 147: 4.09 (unit: kg/m)³) The water-cement ratio was 0.43 and the sand ratio was 36%.

S303, mixing and quality inspection of bamboo concrete components in room

Indoor trial mixing and quality inspection are carried out on the basis of the calculated components of the bamboo concrete:

s3031, feeding method, feeding sequence and stirring time of each component material of bamboo wood concrete component

1. A feeding method. The feeding method of each component material is based on mass feeding.

2. And (4) feeding the materials sequentially. In order to uniformly disperse the bamboo scraps and the thin bamboo strips in the concrete stirring, the feeding sequence of each component material is as follows: sand → bamboo shavings → cement → broken stone → bamboo split filament → water reducing agent → mixing water → stirring and mixing. Feeding of the crushed stones: the crushed stone comprises crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm, and the feeding sequence is that the crushed stone with the granularity of 4.75-9.5 mm is firstly fed, then the crushed stone with the granularity of 9.5-19 mm is fed, and the feeding between the crushed stone and the crushed stone is continuous feeding.

3. And (3) stirring the components of the bamboo concrete for a certain time. The dry mixing time of all the components is 300s, and the stirring time is 180s after all the components are put into the mixer. Firstly, sand is put into a stirrer, then bamboo chips and sand are put into the stirrer to be dry-mixed for 60s, then cement is put into the stirrer to be dry-mixed with the sand and the bamboo chips for 30s, then broken stone is put into the stirrer to be dry-mixed with the sand, the bamboo chips and the cement for 60s, then bamboo skin wires are put into the stirrer to be dry-mixed with the sand, the bamboo chips, the cement, the broken stone and the broken stone for 90s, then water reducing agent is put into the stirrer to be dry-mixed with the sand, the bamboo chips, the cement, the broken stone, the bamboo skin wires and the water reducing agent for 60s, then mixed water, the sand, the bamboo chips, the cement, the broken stone, the bamboo skin wires and the water reducing agent are put into the stirrer to be mixed for 180s, and finally the bamboo concrete mixture is unloaded into a concrete iron plate.

S3032, bamboo wood concrete indoor trial mixing

1. The amount of the trial-mix material. In a concrete component design room with the indoor temperature of 20 +/-5 ℃, components are mixed with 40L of concrete mixture according to the calculation of bamboo concrete, and the following materials are weighed by a 150kg electronic balance with the sensing quantity of 1 g: 13.640kg of cement, 27.480kg of sand, 22.960kg of gravels with the granularity of 4.75-9.5 mm, 25.880kg of gravels with the granularity of 9.5-19 mm, 14g of bamboo chips, 72g of bamboo split filaments, 5.880kg of water and 164g of water reducing agent are weighed.

2. And workability, apparent density detection. Actually measuring slump of the bamboo wood concrete mixture, wherein the actually measured values are 70mm, 65mm and 65mm, the average value is 65mm, and the slump meets the requirement of 50-70 mm slump design; the change of the slump constant of 1h with time is 20 mm; the apparent density was found to be 2370kg/m³Calculating (1.34 percent of measured value of apparent density-calculated value of apparent density)/calculated value of apparent density of the concrete mixture to be less than 2 percent according to item 6.2.3 of standard design rule of common concrete mix proportion (JGJ 55-2011); the concrete mixture has good cohesiveness and water retention, meets the requirement of construction workability, and does not need to correct calculation components of bamboo concrete.

3. According to slump of the bamboo wood concrete mixture and the actual measurement result of 1h time-dependent change, cohesiveness and water retention, the method can obtain the following steps: the bamboo concrete trial mixing component H comprises cement, sand, broken stone with the granularity of 4.75-9.5 mm, broken stone with the granularity of 9.5-19 mm, bamboo chips, bamboo thin bamboo strips, water and a water reducing agent in a mass ratio of 341: 687: 574: 647: 0.36: 1.80: 147: 4.09 (unit: kg/m)³) The water-cement ratio was 0.43 and the sand ratio was 36%.

4. On the basis that the water-cement ratio of the bamboo concrete trial mixing component H group is 0.43, the water-cement ratios are respectively 0.38 and 0.48, and the water consumption is 147kg/m³And (3) calculating to obtain other bamboo concrete components of the G group and the I group according to the mass method:

(1) g group bamboo wood concrete component: the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, broken stone with the granularity of 9.5-19 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is 387: 651: 568: 640: 0.36: 1.80: 147: 4.64 (unit: kg/m)³) The water-cement ratio is 0.38, and the sand rate is 35 percent;

(2) and the group I bamboo wood concrete component: the mass ratio of cement, sand, crushed stone with the granularity of 4.75-9.5 mm, crushed stone with the granularity of 9.5-19 mm, bamboo chips, bamboo thin-bamboo-strip filaments, water and water reducing agent is 306: 718: 575: 648: 0.36: 1.80: 147: 3.67 (unit: kg/m)³) The water-cement ratio is 0.48, and the sand rate is 37%.

S3033, quality inspection

Respectively calculating, weighing and stirring three groups of bamboo wood concrete components with water-cement ratios of 0.38, 0.43 and 0.48 to prepare 500L of concrete mixture, and finishing: the apparent density, slump, 1h time-dependent change, cohesiveness, water retention, air content, condensation time, segregation, water bleeding amount, bamboo chip and thin bamboo strip filament dispersibility, bamboo chip and thin bamboo strip filament volume ratio, bending strength, splitting strength and durability (early crack resistance and abrasion loss) indexes are tested, and the test results are shown in tables 4-1 and 4-2.

TABLE 4-1 comparative analysis table (1) of three groups of bamboo concrete components and cement concrete indoor standard design components with water cement ratio of 0.38, 0.43 and 0.48

TABLE 4-2 comparative analysis table (2) of three groups of bamboo concrete components and cement concrete indoor reference design components with water cement ratio of 0.38, 0.43 and 0.48

S304, determining indoor design components of bamboo concrete

1. The test results of three groups of bamboo wood concrete components with the water cement ratio of 0.38 (group G), 0.43 (group H) and 0.48 (group I) are compared and analyzed with the test results of the standard design components in the cement concrete chamber.

(1) And (3) comparative analysis of the G group design components with the water cement ratio of 0.38 and the cement concrete indoor reference design components:

the test and inspection results of the items of apparent density, slump, 1h time-dependent change, cohesiveness, water retention, gas content, final setting time, segregation and bleeding amount of the bamboo concrete mixture are close to the test and inspection results of the standard design components in the cement concrete chamber; compared with the test and inspection result of the total cracking area of the early reference design component mixture in the cement concrete chamber, the test and inspection result of the total cracking area of the early unit area of the bamboo concrete mixture is reduced by 28.5%; compared with the test result of the abrasion loss test of the cement concrete indoor reference design component concrete, the test result of the abrasion loss test of the bamboo concrete is reduced by 37.3 percent; compared with the bending strength and the splitting strength test results of cement concrete indoor benchmark design component concrete, the bending strength and the splitting strength test results of bamboo concrete are respectively improved by 19.7% and 23.1%.

(2) Comparative analysis of group H design components with a water cement ratio of 0.43 with cement concrete indoor reference design components:

the test and inspection results of the items of apparent density, slump, 1h time-dependent change, cohesiveness, water retention, gas content, final setting time, segregation and bleeding amount of the bamboo concrete mixture are close to the test and inspection results of the standard design components in the cement concrete chamber; compared with the test and inspection result of the total cracking area of the early reference design component mixture in the cement concrete chamber, the test and inspection result of the total cracking area of the early unit area of the bamboo concrete mixture is reduced by 10.1%; compared with the test result of the abrasion loss test of the cement concrete indoor reference design component concrete, the test result of the abrasion loss test of the bamboo concrete is reduced by 15.7 percent; compared with the bending strength and the splitting strength test results of cement concrete indoor benchmark design component concrete, the bending strength and the splitting strength test results of bamboo concrete are respectively improved by 6.1% and 4.8%.

(3) Comparative analysis of group I design components with a water cement ratio of 0.48 with cement concrete indoor reference design components:

the bamboo wood concrete mixture has poor cohesiveness and a small amount of moisture is separated out from the bottom of the mixture; compared with the test result of the indoor standard design component of the cement concrete, the test result of the air content of the bamboo wood concrete mixture is improved by 15 percent; the test and inspection result of the final setting time of the bamboo wood concrete mixture is delayed by 40min compared with the test and inspection result of the indoor standard design component of the cement concrete; a small amount of bamboo scraps and bamboo skin filaments are agglomerated in the bamboo concrete mixture; compared with the test and inspection result of the total cracking area of the early reference design component mixture in the cement concrete chamber, the test and inspection result of the total cracking area of the early unit area of the bamboo concrete mixture is increased by 13.6%; compared with the test result of the abrasion loss test of the cement concrete indoor reference design component concrete, the test result of the abrasion loss test of the bamboo concrete is increased by 4.9 percent; compared with the bending tensile strength and the splitting strength test results of cement concrete indoor benchmark design component concrete, the bending tensile strength and the splitting strength test results of the bamboo concrete are respectively reduced by 7.2 percent and 8.0 percent, and the bending tensile strength of the bamboo concrete is reduced by 4.4 percent compared with the average bending tensile strength of a surface layer bamboo concrete prepared 28 d. The group I design component with a water-cement ratio of 0.48 does not meet the Standard Specification for Highway Cement concrete pavement construction technology rules (JTG/T F30-2014) Standard 4.2.4 the maximum water-cement ratio of 0.46 for the second-class road grade in Table 4.2.4.

2. And comparing and analyzing the test detection results of the bamboo wood concrete components with the water-cement ratio of 0.38 and the water-cement ratio of 0.43 according to the Standard of technical Specifications for construction of Cement concrete road pavement (JTG/T F30-2014), the Standard of technical Specifications for application of fiber concrete (JGJ/T221-2010), the flexural tensile strength, the workability, the durability and the economical efficiency of the components design of the bamboo wood concrete road, and determining the bamboo wood concrete component with the water-cement ratio of 0.43 as the component for designing the bamboo wood concrete chamber.

3. The bamboo concrete indoor design component comprises cement, sand, broken stone with the granularity of 4.75-9.5 mm, broken stone with the granularity of 9.5-19 mm, bamboo chips, bamboo thin bamboo strips, water and a water reducing agent in a mass ratio of 341: 687: 574: 647: 0.36: 1.80: 147: 4.09 (unit: kg/m)³) The water-cement ratio was 0.43 and the sand ratio was 36%.

S4 mixing verification of bamboo concrete mixing station

According to the indoor design component of bamboo wood concrete, the mixing verification of the bamboo wood concrete mixing plant is carried out at the mixing plant, and the mixing verification method comprises the following technical contents:

s401, selecting and customizing the concrete mixing and discharging quantity of not less than 75m per hour according to sand and two crushed stones with granularity when a mixing device is purchased³And the number of the proportioning bins is 3, and the proportioning bins are JS750 type concrete forced mixers with automatic metering standards.

S402, the mixing equipment is debugged, the metering device of the mixing equipment needs to perform regular static calibration of a legal metering and calibrating mechanism and dynamic calibration of the weighing precision of each storage bin of the mixing equipment during use, and the allowable deviation of the weighing precision meets the requirements of relevant construction technical specifications of the state and the industry.

S403, detecting the indoor temperature of the mixing plant and the stacking bin of the components, wherein the temperature needs to be controlled within the range of 20 +/-5 ℃.

S404, detecting the moisture content of the sand, the broken stone with the granularity of 4.75-9.5 mm and the broken stone with the granularity of 9.5-19 mm in the on-site preparation warehouse of the mixing plant.

S405, calculating the feeding amount of each stirring bin of the bamboo wood concrete mixture.

1. The stirring amount per disc is not more than 75% of the rated discharge capacity of the stirrer (i.e. 500L or 0.50 m)³) Calculating, stirring for 1m³And (3) concrete. And calculating the stirring amount of each disc of cement, sand, broken stone, bamboo chips, bamboo strips, water reducing agent and mixing water according to the actually measured water content of the sand, the broken stone with the granularity of 4.75-9.5 mm and the broken stone with the granularity of 9.5-19 mm.

2. The mixing water dosage is as follows: and (3) the calculated amount of the mixing water is reduced by the amount of water in the sand and the crushed stone.

3. Batch metering tolerance (by mass) for each pan of stirred individual constituent materials: the bamboo chips, the thin bamboo strips, the water reducing agent and the mixing water account for +/-1 percent, the cement accounts for +/-2 percent, and the sand and the crushed stone account for +/-3 percent, and meet the specification in the 6.1.1 item of table 6.1.1 of the technical specification for fiber concrete application (JGJ/T221-plus 2010) standard.

S406, a feeding method and a feeding sequence for mixing the bamboo wood concrete with the various components are as follows:

1. the feeding method of each component material comprises the following steps of: the cement, the sand, the broken stone and the mixing water are all added by adopting electronic metering of mixing equipment, and the water reducing agent, the bamboo chips and the bamboo skin wires are all added by manually weighing the mass in advance and then bagging.

2. In order to uniformly disperse the bamboo scraps and the thin bamboo strips in the concrete stirring, the feeding sequence of each component material is as follows: sand (electronic metered input) → bamboo dust (manual input) → cement (electronic metered input) → crushed stone (electronic metered input) → bamboo thin bamboo strips (manual input) → water reducing agent (manual input) → mix water (electronic metered input) → stir-mix.

Feeding of the crushed stones: the crushed stone comprises crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm, and the feeding sequence is that the crushed stone with the granularity of 4.75-9.5 mm is firstly fed, then the crushed stone with the granularity of 9.5-19 mm is fed, and the feeding between the crushed stone and the crushed stone is continuous feeding.

And S407, mixing the bamboo wood concrete with the components for 300S, and mixing the components for 180S after all the components are put into the mixer.

Firstly, sand is put into a stirrer, then bamboo chips and sand are put into the stirrer to be dry-mixed for 60s, then cement is put into the stirrer to be dry-mixed with the sand and the bamboo chips for 30s, then broken stone is put into the stirrer to be dry-mixed with the sand, the bamboo chips and the cement for 60s, then bamboo skin wires are put into the stirrer to be dry-mixed with the sand, the bamboo chips, the cement, the broken stone and the broken stone for 90s, then water reducing agent is put into the stirrer to be dry-mixed with the sand, the bamboo chips, the cement, the broken stone, the bamboo skin wires and the water reducing agent for 60s, then mixed water, the sand, the bamboo chips, the cement, the broken stone, the bamboo skin wires and the water reducing agent are put into the stirrer to be mixed for 180s, and finally the bamboo concrete mixture is unloaded into a concrete transport vehicle.

And S408, detecting sand gradation and broken stone synthesis gradation in the bamboo concrete mixture.

And S409, inspecting the uniformity and color consistency of the bamboo wood concrete mixture.

And S410, detecting the dispersibility and the volume ratio of the bamboo chips and the bamboo skin filaments in the bamboo concrete mixture.

S411, checking the discharge temperature of the bamboo wood concrete mixture, wherein the temperature needs to be controlled within the range of 5-35 ℃.

S412, checking the indexes of apparent density, slump and 1h time-dependent change, cohesiveness, water retention, gas content, condensation time, segregation, bleeding amount, bamboo chip and bamboo strip wire dispersibility, bamboo chip and bamboo strip wire volume ratio, bending strength, splitting strength and durability (early crack resistance and abrasion loss) of the bamboo concrete mixture.

The comparative analysis of the test results of the mixing verification of the bamboo concrete mixing plant and the indoor design components of the bamboo concrete shows that: the parallel test results of the two detection items are close to meet the requirements, and are shown in tables 5-1 and 5-2.

TABLE 5-1 comparative analysis table of mixing verification components of bamboo concrete mixing plant and indoor design components of bamboo concrete (1)

TABLE 5-2 bamboo concrete mixing plant mixing verification component and bamboo concrete indoor design component comparison analysis table (2)

S5 bamboo wood concrete pavement component design component

S501, designing components of bamboo concrete pavement in air temperature range of 20 +/-5 DEG C

According to the comparative analysis of the mixing verification of a bamboo concrete mixing plant and the test detection results of the indoor design components of the bamboo concrete and the batching measurement allowable deviation of each component material in unit volume (by mass, the content of bamboo chips, bamboo thin bamboo strips, a water reducing agent and mixing water is +/-1%, the content of cement is +/-2%, and the content of sand and gravel is +/-3%), determining the design components of the bamboo concrete pavement, which are constructed by the spreading of a three-roller-shaft unit and transporting concrete mixtures by a self-unloading transport vehicle in the air temperature section of 20 +/-5 ℃:

the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (4.05-4.13) (unit: kg/m)³)。

S502, when the self-unloading type transport vehicle with the air temperature of 10 +/-5 ℃ and the air temperature of 30 +/-5 ℃ transports the concrete mixture and the three-roller-shaft unit paves the constructed bamboo concrete pavement component design components, on the basis of the bamboo concrete pavement component design components in the air temperature of 20 +/-5 ℃, the unit dosage of cement, sand, gravel, bamboo chips, bamboo thin bamboo strips and mixing water is kept unchanged, and only the mass mixing amount of the water reducing agent needs to be respectively reduced and increased by 0.3%.

1. Designing components of a bamboo wood concrete pavement in a gas temperature section of 10 +/-5 ℃ as follows: the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (3.04-3.10) (unit: kg/m)³)；

2. Designing components of a bamboo wood concrete pavement in a gas temperature section of 30 +/-5 ℃ as follows: the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (5.07-5.17) (unit: kg/m)³)。

S503, the components of the bamboo wood concrete pavement in the air temperature section of 10 +/-5 ℃, 20 +/-5 ℃ and 30 +/-5 ℃ are designed to meet the requirement of paving construction of pavement concrete at the air temperature of 5-35 ℃.

Pavement paving construction method of bamboo wood concrete

The bamboo concrete pavement paving construction comprises preparation work, paving construction verification, paving construction summary and formal paving construction.

S1, preparation

Before the paving construction, the following preparation work needs to be completed, and the contents comprise:

s101, preparing materials of all components and inspecting the entering field:

1. according to the types and specifications of all the components in the components of the bamboo concrete pavement, the raw materials of all the components on site of the mixing plant are prepared, the storage time of the prepared materials is not more than 5 days, the prepared materials are stacked according to the classification and specification of compartments, and are marked, rain-proof, damp-proof and insect-proof to be kept and managed.

2. Bamboo reinforcement. The method is characterized in that the arrowhead bamboo with clean outer surface, natural organic fiber, green and environment-friendly properties and strong bamboo stalk fiber toughness for more than 3 years is adopted, bamboo chips are stripped and cut from arrowhead bamboo stalks to prepare long-strip bamboo skin chips with the length of 2000-2500 mm, the width of 5-10 mm and the thickness of 2-3 mm, the bamboo skin chips are arranged on the outer layer of the bamboo stalks, and the bamboo skin chips are specially processed and twisted to prepare the bamboo ribs with spiral surfaces and knots.

In order to improve the tensile strength of the thin bamboo strips, enhance the bonding force between the bamboo reinforcement and the concrete and prevent the sliding between the bamboo reinforcement and the concrete, the thin bamboo strips are required to be twisted into the bamboo reinforcement, and the outer surface of the bamboo reinforcement is provided with a spiral shape and a knot.

The twisting method of the bamboo reinforcement comprises the following steps: firstly, 1 thin bamboo strip piece is twisted into 1 strand of bamboo rope by right twisting or left twisting, then 2 strands of bamboo ropes are twisted into bamboo ribs by right twisting or left twisting, and 1 half knot is arranged at the positions of the two ends and the middle part of each bamboo rib at intervals of 500 mm. The diameter of the bamboo reinforcement is determined according to the requirement of the engineering part. Can be formed by twisting 3 or 4 or 5 or more bamboo ropes.

3. Bamboo column. The bamboo is split from a bamboo stalk into long bamboo strips with the length of 400-500 mm, the width of 20-30 mm and the thickness of bamboo stalk, and the long bamboo strips are used for positioning and fixing the installation of the double-layer bamboo rib net. When the bamboo column is used, the bamboo column with harder hardness is selected, and for the bamboo column with softer hardness, 2 long bamboo strips are needed to be oppositely arranged to be in a '()' shape and bound into 1 bamboo column for use.

4. A waterproof coating. SY-J CCCW C type cement-based permeable crystallization type waterproof coating is adopted.

5. And (5) carrying out approach inspection on the material. The method comprises the steps of carrying out relevant quality index inspection on cement, sand, broken stone, bamboo chips, thin bamboo strips, bamboo ribs, bamboo columns, a high-efficiency water reducing agent, mixing water and a waterproof coating before entering a field, carrying out particle size inspection on the bamboo chips, carrying out appearance shape inspection on the thin bamboo strips, carrying out diameter, diameter uniformity and tensile strength inspection on the bamboo ribs, and carrying out hardness and fracture appearance inspection on the bamboo columns. Before entering the field, the bamboo scraps, thin bamboo strips, bamboo columns and bamboo reinforcement materials need to be subjected to insect corrosivity inspection, and the use of the bamboo scraps, thin bamboo strips, bamboo columns and bamboo reinforcement materials corroded by rainwater and insects is strictly forbidden. All inspection results can be used after meeting the requirements of national and industry related construction technical specifications, product standards or technical documents.

6. Soaking the surfaces of the bamboo ribs and the bamboo columns. In order to prevent the fiber-reinforced toughening effect of bamboo ribs and bamboo columns, the bamboo ribs and the bamboo columns are not weakened in the cement paste alkaline solution soaking process, and before use, the bamboo ribs and the bamboo columns are soaked in an A latex solution with the mass concentration of 10% for 24 hours and then drained into a natural drying state for later use.

S102, preparation of construction site

1. Constructing a road base layer and a pavement structure base layer on the original ground of the selected road section to complete quality inspection and acceptance of the pavement structure base layer;

2. roadbed settlement observation and base layer inspection and repair;

3. removing floating soil and broken stone sundries on the surface of the base layer of the pavement structure;

4. and (4) mounting the bamboo columns and the bamboo reinforcement net on the top surface of the base layer of the pavement structure.

(1) And mounting the bamboo columns. The design position of the bamboo columns (the bamboo columns are arranged at the vertical and horizontal intervals and are designed to be 1000mm multiplied by 500mm) on the top surface of the pavement structure base layer is drilled with a percussion drill to obtain round holes with the diameter of 50mm and the depth of 150mm, stone residues in the holes are taken out, and dust in the holes is blown clean. And (2) pouring waterproof mortar (the mixing ratio of the waterproof mortar is cement to sand to water to a waterproof agent is 1: 3: 3.25: 0.05 (mass ratio)) into the circular hole to the top surface of the hole, vertically inserting the bamboo column which is soaked and drained on the surface into the hole for 120mm of depth, repeatedly inserting the bamboo column into the hole for 3-5 times from top to bottom, enabling the waterproof mortar to overflow out of the top surface of the hole, ensuring that the waterproof mortar is tightly filled with the bamboo column and the hole wall pores in the hole, mounting the bamboo rib net after the waterproof mortar is finally set, cutting off the redundant part of the height of the bamboo column after the top layer bamboo rib net is mounted, enabling the height of the mounted bamboo column to be slightly higher than that of the top layer bamboo rib net by 20-30 mm, and enabling the bamboo column to be provided with a 120-130 mm concrete protective layer on the top surface of the pavement structure, and enabling the bamboo column to be free from corrosion caused by wetting by insects and rainwater.

(2) And installing the bamboo reinforcement net. Firstly, when the bottom layer bamboo rib net is installed, the bamboo ribs which are soaked on the surface and drained are sequentially wound around each bamboo column for one circle along the horizontal length direction to form warp-direction bamboo ribs, and the bamboo ribs are woven in a staggered mode along the horizontal width direction to form the bottom layer bamboo rib net. The crossed nodes of the bamboo rib grids are firmly bound by adopting bamboo ropes, the binding is bound by adopting an 8-shaped mode of changing the direction of the bamboo ropes point by point in a staggered way or a cross mode of double diagonal lines, and the side length of the grids is 200 mm; secondly, the installation of the top layer bamboo rib net is finished by adopting the same method at the installation design position of the top layer bamboo rib net. And thirdly, the two bamboo ribs are connected by adopting a rope knot method, and the connection needs to be firm and not to loosen.

(3) And a bamboo reinforcement net concrete protective layer. After the bamboo reinforcement net is installed, the distance of 100mm is kept between the bottom layer bamboo reinforcement net and the top surface of the pavement structure base layer; the distance between the bottom layer bamboo rib net, the top layer bamboo rib net and the steel formworks at the construction joints or expansion joints of the pavement structure surface layer is kept at 100mm, so that the bamboo rib net has a concrete protective layer with enough thickness and is prevented from being corroded by insects and rainwater; the distance of 150mm is kept between the top layer bamboo rib net and the top surface of the pavement structure surface layer, so that the condition that the stress of the bamboo ribs and the bamboo rib net is influenced by cutting and breaking the bamboo ribs when the pavement structure surface layer contracts and cuts seams. The erection height of the double-layer bamboo rib net is determined by deducting the thickness of the upper and lower concrete protective layers of the bamboo rib net according to the thickness of the pavement structural surface slab.

5. Erecting an L-shaped steel template, and installing and fixing a dowel bar.

6. The concrete discharging device which can automatically walk back and forth and has the functions of stirring and vibration control and can move left and right of the discharging opening is arranged at the top of the steel template.

7. The concrete vibrator capable of automatically walking is installed on the top of the steel formwork.

8. And a three-roller shaft leveling machine is arranged at the top of the steel template.

9. And other auxiliary equipment and tools such as a vibrating machine, a grinding machine and the like required by the paving construction of the bamboo concrete pavement.

10. The power supply equipment and the power supply circuit required by construction site illumination, concrete vibrator, three-roller shaft leveler, and grinding machine are installed.

11. Measurement, test and quality detection equipment and detection tools.

S2, paving construction verification

Outside a paving construction area of a bamboo wood concrete pavement on a construction site, an embankment and cutting transition section with the length of no less than 100m and the width of 3.5m or a half-filled and half-dug embankment or a soft soil foundation is selected to treat an embankment or an easily subsided and unstable section of a high embankment with the maximum filled soil slope height of more than 20m for paving construction verification.

S201, verifying contents of paving construction

1. And determining the mixing parameters, the actual production capacity and the batching precision of a mixing plant of the mixing station.

2. And (5) inspecting the construction performance and technical parameters of the concrete.

3. And (5) checking the paving machinery, process parameters and the matching condition with the mixing capability.

4. Actually measuring the temperature of the bamboo wood concrete pavement paving construction site, and determining the component design components of the bamboo wood concrete pavement used by the temperature.

5. And actually measuring the finish time of the concrete surface finish surface after the bamboo wood concrete mixture is discharged to the paving construction site, and verifying whether the initial setting time and the final setting time of the concrete of the indoor design components of the bamboo wood concrete meet the paving construction requirements of the construction site.

6. Actually measuring slump, segregation, bleeding quantity, bamboo chip and bamboo strip filament dispersibility, bamboo chip and bamboo strip filament volume ratio, loose paving coefficient, paving speed, vibration time and frequency, bending strength, splitting strength and durability (early crack resistance and abrasion loss) of the bamboo concrete.

7. Actually measuring the anti-skid structure depth and the friction coefficient of the bamboo concrete pavement concrete;

8. and (3) actually measuring the bubble spacing coefficient of the bamboo concrete pavement concrete by drilling a core sample, checking the size and uniformity of bubbles and the compactness of the bamboo concrete pavement concrete, and verifying the adaptability of the bamboo concrete pavement component design components and the concrete vibrator paved on a construction site.

S202, mixing bamboo wood concrete

According to the temperature condition of the day, the mixing station selects the component design components of the bamboo wood concrete pavement of the corresponding temperature section, and detects the water content of sand, crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm in a field preparation storage warehouse of the mixing station. And (3) mixing the concrete according to the mixing verification step of the bamboo concrete mixing plant, and carrying out temperature, apparent density, slump, cohesiveness, water retention, gas content, condensation time, segregation, bleeding, bamboo chip and bamboo strip filament dispersibility and bamboo chip and bamboo strip filament volume ratio inspection on the concrete mixture at the discharge port of the mixing plant.

And S203, transporting the bamboo concrete. Transporting the bamboo wood concrete mixture which is stirred and qualified by inspection to a bamboo wood concrete paving site on a construction site by adopting a self-unloading type transport vehicle; the bamboo wood concrete mixture is transported to a bamboo wood concrete paving site in a construction site within the initial setting time, and concrete vibration and concrete surface smoothing are completed.

And S204, discharging the bamboo concrete. In order to protect the bamboo reinforcement net installed on the top surface of a road surface structure base layer of a processed embankment or a road surface structure base layer of a high embankment section with the maximum slope height of filled soil larger than 20m at an embankment and cutting transition section or a half-filled and half-dug embankment or a soft soil foundation from being rolled and damaged by a transport vehicle, concrete mixture conveyed to a construction site by a lane outside the bamboo concrete pavement needs to be unloaded from a self-unloading transport vehicle into a concrete unloading device which can automatically walk forwards and backwards, has the stirring and vibration control functions and can move left and right at an unloading opening to carry out secondary stirring before paving. The uniformity and the color consistency of the bamboo concrete mixture are ensured, and the bamboo chips and the bamboo skin wires are uniformly dispersed in the concrete stirring. Performing slump, cohesiveness, water retention, segregation and bamboo chip and thin bamboo strip wire dispersibility test on the concrete mixture stirred for the second time, and adding a water reducing agent when the slump is smaller than 20mm and does not meet the construction requirement of 20-40 mm on-site slump under the faithful measurement, keeping the raw water-cement ratio unchanged, and stirring again; if the actually measured slump is larger than 40mm and does not meet the construction requirement of 20-40 mm on-site slump, the raw water-cement ratio of the bamboo concrete is kept unchanged during mixing the bamboo concrete, the mass mixing amount of the water reducer is reduced, and the concrete can not be paved until the uniformity and the slump of the bamboo concrete mixture meet the construction requirement.

S205, paving the bamboo wood concrete. A hanging plate with the width being 3.5m as that of the paving is welded at the tail part of the forward walking of the concrete discharging device, concrete mixture is automatically hung and leveled while the concrete discharging device discharges, and the height of the bamboo wood concrete mixture after being hung and leveled is not higher than the top surface of the L-shaped steel template by 50 mm; the forward traveling speed of the concrete discharging device is 2 m-3 m/min, and the distance between the concrete discharging device and the vibrating position of the concrete vibrator is 3 m-5 m; the bamboo wood concrete paving speed is adaptive to the bamboo wood concrete mixture conveying speed, and the phenomenon that more raw materials are wasted or the materials are stopped when the materials are equal is avoided.

And S206, vibrating the bamboo concrete. In order to ensure the dispersion uniformity of bamboo chips and thin bamboo strips in bamboo concrete, an inserted vibrating rod is not allowed to be used for vibrating the concrete. During vibration, a concrete vibrating plate with the power of 9kW, the length of 3.5m and the width of 3.00m is adopted to vibrate and discharge slurry comprehensively. The forward running speed of the concrete vibrator is 1-2 m/min.

S207, leveling three rollers of bamboo concrete, finely leveling, curing, grooving, slitting, joint filling, water proofing and corrosion proofing, and quality acceptance and assessment of the bamboo concrete pavement, and construction, quality acceptance and assessment are carried out according to relevant regulations in Highway concrete pavement construction technical Specifications (JTG/T F30-2014).

Wherein, the waterproof and anticorrosion construction comprises the following steps:

1. and (5) constructing a waterproof coating. After the L-shaped steel template is removed in each construction operation section, two SY-J CCCW C type cement-based capillary crystalline waterproof coatings are respectively coated on the exposed surfaces of the two ends of the bamboo concrete layer in the length direction and the two sides of the bamboo concrete layer in the width direction in time to form a waterproof coating, so that the corrosion caused by wetting by insects and rainwater is prevented.

2. And (5) waterproof and anticorrosion construction of the joint filling layer. The gap filling layer comprises a construction gap or an expansion gap or a contraction gap. The joint filling construction is carried out at the construction joint, the expansion joint or the contraction joint of the pavement structure surface layer according to relevant regulations in the highway cement concrete pavement construction technical rules (JTG/T F30-2014) standard, so that the phenomenon that the surface water of the pavement structure surface layer permeates into the construction joint, the expansion joint or the contraction joint, soaks bamboo chips, bamboo thin bamboo strips, bamboo columns and bamboo ribs, is corroded by insects and rainwater, the filling compactness of the bamboo chips is reduced, and the mechanical properties of the bamboo thin bamboo strips, the bamboo columns and the bamboo ribs are reduced. After the construction of joint filling, the center of the joint filling surface is higher than the top surface of the bamboo concrete layer panel of the pavement structure at the two sides of the joint filling layer by 2-3 mm and is in a convex shape, and the joint filling width covers the bamboo concrete layer of the pavement structure at the two sides of the joint filling layer and each side of the waterproof coating by 2-3 mm. The center of the joint filling surface at the contraction joint is kept flush with the top surfaces of the bamboo concrete layer panels of the pavement structure at the two sides of the contraction joint. Traffic must be closed during the curing of the joint compound.

3. And (5) maintaining. And after the bamboo concrete is paved and formed, a plastic film is adopted to cover and maintain in time, and the maintenance time is not less than 7 d.

S3, paving construction summary

And after the quality of the bamboo wood concrete pavement is checked, accepted and evaluated, the component design and the paving construction verification of the bamboo wood concrete pavement are summarized in time for paving construction, and construction guidance is provided for the formal paving construction of the bamboo wood concrete pavement in the later period.

S4, construction of formal pavement

And (3) carrying out bamboo concrete pavement paving construction on the road or the terrace pavement according to the technical parameters summarized by the bamboo concrete pavement paving construction verification steps and the paving construction.

Also comprises a control method for preventing the bamboo wood from water resistance, corrosion resistance and fiber reinforcement and toughening function reduction

1. Bamboo scraps and thin bamboo strips. Before use, the bamboo chips and the thin bamboo strips are soaked in an A latex solution with the mass concentration of 10% for 24 hours and then drained to be in a natural dry state, so that the fiber reinforcement and toughening effects of the bamboo chips and the thin bamboo strips are prevented, and the bamboo chips and the thin bamboo strips are not weakened in the cement paste alkaline solution soaking process.

2. Bamboo rib net. (1) Before the bamboo reinforcement is used, the bamboo reinforcement is soaked in an A latex solution with the mass concentration of 10% for 24 hours and then drained to be in a natural dry state, so that the fiber reinforcement and toughening effects of the bamboo reinforcement are prevented, and the bamboo reinforcement is not weakened in the cement paste alkaline solution soaking; (2) controlling the thickness of the concrete protective layer of the bamboo rib net: after the bamboo reinforcement net is installed, the distance of 100mm is kept between the bottom layer bamboo reinforcement net and the top surface of the pavement structure base layer; the distance between the bottom layer bamboo rib net, the top layer bamboo rib net and the steel formworks at the construction joints or expansion joints of the pavement structure surface layer is kept at 100mm, so that the bamboo rib net has a concrete protective layer with enough thickness and is prevented from being corroded by insects and rainwater; the distance of 150mm is kept between the top layer bamboo rib net and the top surface of the pavement structure surface layer, so that the bamboo ribs are prevented from being cut off when the pavement structure surface layer is subjected to shrinkage joint cutting, and the stress of the bamboo ribs and the bamboo rib net is prevented from being influenced; the erection height of the double-layer bamboo rib net is determined by deducting the thickness of the upper and lower concrete protective layers of the bamboo rib net according to the thickness of the pavement structural surface slab.

3. Bamboo column. Before the bamboo column is used, the bamboo column is soaked in an A latex solution with the mass concentration of 10% for 24 hours and then is drained into a natural dry state, so that the fiber reinforcement and toughening effects of the bamboo column are prevented and the bamboo column is not weakened in the cement paste alkaline solution soaking process; when the bamboo columns are installed, the bamboo columns which are soaked on the surfaces and drained are vertically inserted into the holes for a depth of 120mm, and the bamboo columns are repeatedly inserted for 3-5 times from top to bottom, so that the waterproof mortar overflows the top surfaces of the holes, and the waterproof mortar is guaranteed to be tightly filled with the bamboo columns and the holes of the holes in the holes; after the top layer bamboo rib net is installed, the redundant part of the height of the bamboo column is cut off, the height of the installed bamboo column is slightly higher than that of the top layer bamboo rib net by 20-30 mm, and a concrete protective layer with the thickness of 120-130 mm is arranged on the top surface of the pavement structure surface layer, so that the bamboo column is prevented from being corroded by insects and rainwater in a soaking mode.

4. Bamboo wood concrete waterproof coating. After the L-shaped steel template is removed in each construction operation section, two SY-J CCCW C type cement-based capillary crystalline waterproof coatings are respectively coated on the exposed surfaces of the two ends of the bamboo concrete layer in the length direction and the two sides of the bamboo concrete layer in the width direction in time to form a waterproof coating, so that the corrosion caused by wetting by insects and rainwater is prevented.

5. And (5) waterproof and anticorrosion construction of the joint filling layer. The gap filling layer comprises a construction gap or an expansion gap or a contraction gap. The joint filling construction is carried out at the construction joint, the expansion joint or the contraction joint of the pavement structure surface layer according to the relevant regulations in the highway cement concrete pavement construction technical rules (JTG/T F30-2014), so that the surface water of the pavement structure surface layer is prevented from permeating into the construction joint, the expansion joint or the contraction joint, the bamboo chips, the bamboo thin bamboo strips, the bamboo columns and the bamboo ribs are prevented from being soaked, and the corrosion of insects and rainwater is avoided, the filling compactness of the bamboo chips is reduced, and the mechanical properties of the bamboo thin bamboo strips, the bamboo columns and the bamboo ribs are reduced. After the joint filling construction, the center of the joint filling surface is 2-3 mm higher than the top surfaces of the bamboo concrete layer panels of the pavement structures at the two sides of the joint filling layer and is in a convex shape, and the joint filling width covers 2-3 mm of each side of the bamboo concrete layer and the waterproof coating of the pavement structures at the two sides of the joint filling layer; the center of the joint filling surface at the contraction joint is kept flush with the top surfaces of the bamboo concrete layer panels of the pavement structure at the two sides of the contraction joint. Traffic must be closed during the curing of the joint compound.

6. And (5) maintaining. And after the bamboo concrete is paved and formed, a plastic film is adopted to cover and maintain in time, and the maintenance time is not less than 7 d.

When the varieties and the quality of all the components of the bamboo concrete pavement are obviously changed, or the difference value of the fineness modulus of the front batch and the rear batch of the sand exceeds 0.3, or other transportation modes and paving methods are adopted for paving construction, the component design of the bamboo concrete pavement needs to be carried out again according to the steps.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A bamboo concrete, comprising:

the mass ratio of the cement to the sand to the broken stone to the bamboo chips to the thin bamboo strips to the water reducing agent is (335-347), to (667-707), to (1185-1257), to (0.357-0.363), to (1.783-1.817), to (146-148) to (3.04-5.17).

2. Bamboo concrete according to claim 1,

the crushed stone comprises crushed stone with the granularity of 4.75-9.5 mm and crushed stone with the granularity of 9.5-19 mm;

the mass ratio of the crushed stone with the granularity of 4.75-9.5 mm to the crushed stone with the granularity of 9.5-19 mm is (557-591): (628-666).

3. Bamboo concrete according to claim 1,

the bamboo wood concrete with the air temperature of 10 +/-5 ℃ in the air temperature section comprises the following components:

the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (3.04-3.10); and/or

The bamboo wood concrete with the air temperature of 20 +/-5 ℃ in the air temperature section comprises the following components:

the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin bamboo strips, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (4.05-4.13); and/or

The bamboo wood concrete with the air temperature of 30 +/-5 ℃ in the air temperature section comprises the following components:

the mass ratio of cement, sand, broken stone with the granularity of 4.75-9.5 mm, bamboo chips, bamboo thin-bamboo-strip filaments, water and water reducing agent is (335-347), to (667-707), to (557-591), to (628-666), to (0.357-0.363), to (1.783-1.817), to (146-148) to (5.07-5.17).

4. Bamboo concrete according to claim 1,

the granularity of the bamboo dust is less than or equal to 0.6 mm; and/or

The bamboo thin bamboo strip filaments have the length of 15-20 mm, the width of 2.0-3.0 mm and the thickness of 1.0-1.5 mm; and/or

The surface shape of the bamboo skin silk adopts one or more of a strip shape, a trapezoid shape, a needle point shape, an arrow tail shape and an ellipse shape.

5. A method for preparing bamboo concrete according to any one of claims 1 to 4, characterized by comprising the following steps:

6. The method for preparing bamboo concrete according to claim 5,

the preparation of the bamboo scraps and thin bamboo strips in the step S3 comprises the following steps:

(1) determining the length and unit dosage of the thin bamboo strips:

the volume ratio of the thin bamboo strips is selected to be 0.20-0.30%, and the unit consumption of the thin bamboo strips is 1.44kg/m³～2.16kg/m³；

The unit dosage of five samples with the lengths of 5-10 mm, 10-15 mm, 15-20 mm, 20-25 mm and 25-30 mm which are subjected to surface soaking treatment and drained is 1.44kg/m³、1.80kg/m³、2.16kg/m³The bamboo skin wires are respectively mixed with the standard design components in the cement concrete chamber to prepare concrete mixtures, and the workability, segregation, bleeding amount and the dispersibility of the concrete mixtures are tested to determine the length and unit dosage of the bamboo skin wires;

(2) determining the unit dosage of the bamboo dust:

calculating according to the total volume rate of the bamboo scraps and the thin bamboo strips not exceeding 0.30 percent, and determining the volume rate and unit dosage of the bamboo scraps;

(3) preparing bamboo scraps and thin bamboo strips and surface soaking:

preparing materials according to the specifications of selected bamboo scraps and thin bamboo strips, stacking the materials according to classes and specifications in separate bins, soaking the materials in an A latex solution with the mass concentration of 10% for at least 24 hours before use, and draining.

7. The method for preparing bamboo concrete according to claim 5,

the indoor trial mixing and quality inspection of bamboo wood concrete components in the step S3 comprises the following steps:

(1) the feeding method, the feeding sequence and the stirring time of the components of the bamboo wood concrete are as follows:

mixing bamboo chips with sand for at least 60s, adding cement, sand and bamboo chips, mixing for at least 30s, adding broken stone, sand, bamboo chips and cement, mixing for at least 60s, adding bamboo skin silk, sand, bamboo chips, cement and broken stone, mixing for at least 90s, adding a water reducing agent, sand, bamboo chips, cement, broken stone and bamboo skin silk, mixing for at least 60s, and adding mixing water, sand, bamboo chips, cement, broken stone, bamboo skin silk and the water reducing agent, and mixing for at least 180 s;

(2) mixing bamboo wood concrete indoors;

(3) and (5) quality inspection.

8. A pavement paving construction method of bamboo concrete according to any one of claims 1 to 4, characterized by comprising the steps of:

9. The bamboo concrete pavement paving construction method according to claim 8,

the preparation of each component material in the step S1 includes:

preparing bamboo ribs, twisting long thin bamboo strips with the length of 2000-2500 mm, the width of 5-10 mm and the thickness of 2-3 mm into bamboo ropes with spiral surfaces, twisting at least 2 bamboo ropes into bamboo ribs, and arranging knots on the surfaces of the bamboo ribs at intervals;

preparing bamboo columns, namely preparing bamboo stalks into the bamboo columns with the length of 400-500 mm and the width of 20-30 mm;

soaking the surfaces of the bamboo ribs and the bamboo columns for at least 24 hours in an A latex solution with the mass concentration of 10% before use, and draining.

10. The bamboo concrete pavement paving construction method according to claim 8,

the job site preparation in step S1 includes:

installing the bamboo columns, drilling holes at the designed positions of the bamboo columns on the top surface of the pavement structure base layer to obtain blind holes, filling the blind holes with waterproof mortar, inserting the bamboo columns into the blind holes, and waiting for the waterproof mortar to be condensed;

the bamboo rib net is arranged at the lower part of the bamboo column, the bamboo ribs are sequentially wound around each bamboo column for one circle along the horizontal length direction to form warp-direction bamboo ribs, the bamboo ribs are woven in a staggered mode with the warp-direction bamboo ribs one above another along the horizontal width direction to form a bottom layer bamboo rib net, the bamboo rib net is arranged at the upper part of the bamboo column, and a top layer bamboo rib net is formed by adopting the same method as the bottom layer bamboo rib net;

the distance from the top end of the bamboo column to the top layer bamboo rib net is 20-30 mm;

the distance from the bottom layer bamboo rib net to the top surface of the pavement structure base layer is more than or equal to 100 mm.