Bamboo reinforcement system for reinforcing high-fill roadbed in mountainous area and construction method
Technical Field
The invention relates to a high fill roadbed processing construction method, in particular to a bamboo wood reinforcement system for reinforcing a high fill roadbed in a mountainous area and a construction method.
Background
As the construction of the expressway in China gradually advances to the mountainous areas in the west, the construction of a plurality of roadbeds needs to be completed by filling rock and soil mass materials on the original slope and compacting the rock and soil mass materials. Because one side of the roadbed is an original state slope and the other side is other rock-soil body materials, a natural interface exists between the filling section and the original state slope, and because of the difference of the rock-soil body materials at the two sides of the interface in the aspects of composition, physical and mechanical properties, compactness and the like, the two sides of the interface are easy to slide or settle unevenly especially under the condition of influence of rainwater or underground water; meanwhile, the high-fill roadbed adopts layered filling and compaction construction processes for the same or different filling materials, and the processes easily cause the problems of uneven rolling at layered interfaces, inconsistent compactness of upper and lower layers, difficulty in forming a stable whole body in the whole embankment and the like.
The problems of relative sliding, uneven settlement, inconsistent compactness and the like of two sides of the interface easily cause damage and destruction of the roadbed, and further cause pavement cracking seriously, so that the problem of the interface between a filling material and an original slope, between different filling materials and between layered filling surfaces is one of important problems in the construction of high-fill roadbed engineering.
At present, the construction method of excavating steps, filling in layers and laying geogrids is generally adopted in high fill embankment engineering, and four problems mainly exist:
(1) the filling mode of the excavation step, the problem such as slippage, uneven settlement and the like easily occur at the interface.
(2) The problems of uneven rolling, inconsistent compactness and the like easily occur at the interface of the upper layer and the lower layer in a layered filling mode.
(3) When the geogrid is used for reinforcing, one part of the geogrid is located on an original slope surface, the other part of the geogrid is located on a filling material, and the geogrid is easy to form an arch shape in a structure during later rolling, so that the roadbed is very unfavorable for stability.
(4) Geogrids are made of chemical synthetic materials, the materials are buried in soil for a long time, soil pollution is serious, a large amount of energy is consumed in the production process, a large amount of waste residues, waste water and waste gas are generated, and the geogrids are seriously inconsistent with the design concept of energy conservation, environmental protection and sustainable development advocated in the current engineering construction.
Disclosure of Invention
The invention aims at the problems that in the existing construction method, the interface of the excavation step filling mode is easy to slide and settle unevenly, and the interface of the upper layer and the lower layer of the layered filling mode is easy to roll unevenly and have inconsistent compactness; the use of geogrids, which are chemically synthesized materials, consumes a large amount of energy in the production process and causes problems of a large amount of waste residues, waste water and waste gas. The bamboo wood reinforcement system and the construction method for reinforcing the high-fill roadbed in the mountainous area have the advantages of resource saving, environment-friendly materials, low cost and convenience in construction, and can meet various functional requirements.
In order to achieve the purpose, the invention adopts the following technical scheme:
a bamboo wood reinforcement system for reinforcing a high-fill roadbed in a mountainous area and a construction method thereof comprise the following steps:
(1): grading the site according to soil texture, terrain and gradient, wherein the grading of the site can be divided into four grades I, II, III and IV;
(2): determining a site reinforcement mode, wherein the site reinforcement mode comprises the following steps: in the I-level field, steps are excavated on the original slope ground, and roadbed layered filling and rolling are directly carried out without reinforcing ribs; in the level II field, bamboo vertical reinforcement needs to be added on the basis of the construction process of the level I field; in the level III site, bamboo vertical ribs and bamboo horizontal ribs are added on the basis of the level I site construction process; in the IV-level site, bamboo vertical ribs, bamboo horizontal ribs and bamboo cavity grouting need to be added on the basis of the construction process of the I-level site.
(3): processing bamboo wood; the bamboo processing comprises the following steps:
manufacturing ① A type bamboo tube sections;
② B type bamboo tube section production;
③ preparing bamboo ribs;
④ performing insect-proof, antiseptic and waterproof treatment on the A-type bamboo tube section, the B-type bamboo tube section and the strip bamboo reinforcement respectively.
(4): performing reinforcement construction and filling and rolling; the reinforcement construction and filling rolling comprises the following processes:
①, processing the substrate;
②, excavating slope steps;
③, carrying out vertical reinforcement on the bamboo tube, leading holes on the compacted filling layer, driving A-type or B-type bamboo tube sections into the holes, and carrying out vertical reinforcement, wherein the depth of the bamboo tube sections in the ground is 400mm, the transverse spacing of the bamboo tube sections is 700mm within the range of the transverse extension of 1000mm of the excavation step part, the longitudinal and transverse spacing of the bamboo tube sections of the other filling parts are 1000mm, and the bamboo tube sections are arranged between the upper filling layer and the lower filling layer in a crossed manner, wherein the transverse spacing of the A-type or B-type bamboo tube sections arranged at the base is 700mm, and the longitudinal spacing of the A-type or B-type;
④, horizontally reinforcing the bamboo ribs, horizontally paving the bamboo ribs above the compacted filling layer along the transverse direction and the longitudinal direction, and fixedly connecting the bamboo ribs with the A or B type bamboo tube sections by using steel wires to form a rectangular bamboo rib grid, wherein the strip bamboo ribs with insufficient length can be spliced with each other, the spliced parts are firmly bound by using the steel wires, the superposed length of the two strip bamboo ribs is not less than 100mm, and diagonal bamboo ribs can be properly arranged within 2000mm of the filling interface for reinforcement;
⑤, grouting the bamboo tube, pressing cement slurry into the cavity of the B-shaped bamboo tube, and sealing the bamboo tube cavity, wherein the original slope part and the base part are dense-grouting sections, and the other parts for filling the roadbed are dilute-grouting sections;
⑥, filling roadbed, reinforcing, filling and compacting single layer of embankment, and constructing layer by layer upwards, wherein the filling height of each layer of the same material is not less than 500mm, and different filling materials need to be layered;
⑦ smoothing and rolling.
Further, the site grading mode in the step (1) is specifically as follows:
the I-level field is as follows: (1) the soil compactness is better, the gradient is less than 1: 5(2), the soil compactness is better, the gradient is more than 1: 1.5, less than 1: 2.5(3) loose soil and crushed soil stones, the gradient is less than 1: 5;
the II-level field is as follows: (1) the soil has good compactness, the gradient is larger than 1: 2.5(2), the loose soil and the crushed stone are clamped, the gradient is larger than 1: 1.5 and smaller than 1: 2.5(3), the weathered rock mass and the loose crushed stone soil are formed, and the gradient is smaller than 1: 5;
the III-grade site is as follows: (1) loose soil and crushed soil stones, weathered rock bodies and loose crushed soil with the gradient larger than 1: 2.5(2), weak soil such as paddy fields, lakes and the like with the gradient larger than 1: 1.5 and smaller than 1: 2.5(3), and weathered crushed rock bodies and expanded soil with the gradient smaller than 1: 5;
the IV-level site is as follows: (1) the slope of the weathered rock mass and the loose gravel soil is greater than 1: 2.5(2) of the soft soil such as the rice field and the lake, and the slope of the weathered broken rock mass and the expansive soil is greater than 1: 1.5 and less than 1: 2.5(3) of the soft soil such as the rice field and the lake and greater than 1: 2.5 of the weathered broken rock mass and the expansive soil.
Further, the bamboo wood processing in the step (3) comprises specific manufacturing modes of ①, ② and ③ as follows:
① A type bamboo tube section is prepared by selecting Mao bamboo material with outer diameter of 40-60 mm, cutting into bamboo tube section with length of 800mm, and sharpening one end of the bamboo tube section;
② B type bamboo tube section is prepared by selecting Mao bamboo material with outer diameter of 40-60 mm, cutting into bamboo tube section with length of 800mm, opening bamboo joint of the bamboo tube section, making the interior of the bamboo tube section into one-way through type bamboo tube cavity, leaving a section of bamboo joint at the bottom of the bamboo tube section without through, sharpening one end of the bamboo joint, and arranging a hole in the range of 300mm upward from the bottom of the bamboo tube section;
③ preparing bamboo rib by making the rest bamboo material into strip bamboo rib with width of 15-30 mm and length of more than 50 mm.
Further, the treatment at the site of the flow ① in the step (4) is embodied in such a manner that the roadbed filling should first remove the turf, humus, etc. of the substrate and the substrate should be properly chiseled.
Furthermore, the flow ② in the step (4) is specifically to excavate the slope steps, excavate the steps at the interface of the filling section, the transverse length of the steps is not less than 2000mm, the vertical height is not more than 3000mm, and the upper step and the lower step are continuous.
Further, in step (4), the flow ⑦ is specifically leveling and rolling, layering and compacting in sections are performed along the longitudinal direction of the road, so that the construction of a new filling layer is completed, and then the construction of the next layer can be repeated from step ② to the top surface of the roadbed.
Drawings
FIG. 1 is a schematic view of a type A bamboo tube segment according to the present invention;
FIG. 2 is a schematic view of a type B bamboo tube segment according to the present invention;
FIG. 3 is a schematic view of the bamboo vertical reinforcement of the present invention;
FIG. 4 is a plan view of the bamboo material of the present invention, with vertical and horizontal ribs;
FIG. 5 is a top view of the vertical and horizontal reinforcement of the bamboo material of the present invention;
FIG. 6 is a schematic view of vertical and horizontal reinforcement and bamboo cavity grouting of bamboo material in the invention;
wherein, 1 is a grouting port; 2 is a bamboo tube cavity; 3 is a grouting hole; 4 is a bamboo joint; 5 is a roadbed roof; 6, filling a rolling layer; 7 is an A-shaped bamboo tube section; 8 is bamboo reinforcement; 9 is cement slurry; 10 is a substrate; 11, excavating steps; 12 is an original slope surface line; 13 is a catch water ditch; 14 is a slope body.
Detailed Description
The invention is further described with reference to the following drawings and detailed description.
Example 1:
and (3) roadbed filling construction under I-level working conditions:
foundation treatment step ① roadbed filling is performed by first removing the turf, humus, etc. of the foundation and then appropriate roughening treatment is performed on the foundation.
And ②, excavating slope steps, excavating the steps at the interface of the filling section, wherein the transverse length of the steps is not less than 2000mm, the vertical height of the steps is not more than 3000mm, and the upper step and the lower step are continuous.
And ③, filling a roadbed, filling the embankment layer by layer, wherein the filling height of each layer of the same material is not less than 500mm, different filling materials need to be layered, the roadbed is filled by adopting a transverse segmentation and vertical layering mode to construct layer by layer from the lowest part upwards, and the same layer is constructed by adopting a mode of filling from two sides to the middle.
And ④, leveling and rolling, primarily leveling the newly-filled layer to ensure that the layer surface has no obvious local concave-convex, layering and compacting in sections along the longitudinal direction of the line to finish the construction of the newly-filled layer, and then repeating the step ② to carry out the construction of the next layer until the height of the top surface of the roadbed.
Example 2:
for roadbed filling construction under II-level working conditions, as shown in figure 3:
foundation treatment step ① roadbed filling is performed by first removing the turf, humus, etc. of the foundation and then appropriate roughening treatment is performed on the foundation.
And ②, excavating slope steps, excavating the steps at the interface of the filling section, wherein the transverse length of the steps is not less than 2000mm, the vertical height of the steps is not more than 3000mm, and the upper step and the lower step are continuous.
③, vertically reinforcing the bamboo tube, leading holes in the compacted filling layer and driving A-shaped bamboo tube sections, as shown in figure 1, vertically reinforcing the bamboo tube sections, wherein the ground penetration depth of the bamboo tube sections is 400mm, the leading hole depth is slightly less than 400mm, the sharpening treatment of one end of the bamboo tube sections can facilitate the bamboo tube sections to be driven into the ground, the transverse distance of the bamboo tube sections is 700mm within the range that the excavation step part is transversely extended by 1000mm, the longitudinal and transverse distances of the bamboo tube sections of the rest filling parts are 1000mm, the bamboo tube sections are arranged between the upper filling layer and the lower filling layer in a crossing mode, and further, the transverse distance of the A-shaped bamboo tube sections arranged at the base is 700mm and the longitudinal distance is 1000 mm.
The vertical reinforcement of the bamboo tube improves the vertical bearing capacity of the filled roadbed on one hand, and on the other hand, the interfaces between the upper layer and the lower layer of the same material and at the layering positions of different materials are not easy to slide during rolling or later service, so that the problems of uneven settlement, inconsistent compactness and the like at the interfaces are effectively prevented;
and ④, performing roadbed filling, vertical reinforcement, filling and compaction on a single layer of the embankment, and further performing upward construction layer by layer, wherein the filling height of each layer of the same material is not less than 500mm, different filling materials need to be layered, the roadbed filling adopts a transverse segmentation and vertical layering mode to perform upward layer by layer from the lowest part, and the same layer adopts a mode of filling from two sides to the middle.
And ⑤, leveling and rolling, primarily leveling the newly-filled layer to ensure that the layer surface has no obvious local concave-convex, layering and compacting in sections along the longitudinal direction of the line to finish the construction of the newly-filled layer, and then repeating the step ② to carry out the construction of the next layer until the height of the top surface of the roadbed.
Example 3:
for roadbed filling construction under the III-level working condition, as shown in figure 4:
foundation treatment step ① roadbed filling is performed by first removing the turf, humus, etc. of the foundation and then appropriate roughening treatment is performed on the foundation.
And ②, excavating slope steps, excavating the steps at the interface of the filling section, wherein the transverse length of the steps is not less than 2000mm, the vertical height of the steps is not more than 3000mm, and the upper step and the lower step are continuous.
③, vertically reinforcing the bamboo tube, leading holes in the compacted filling layer and driving A-shaped bamboo tube sections into the holes for vertically reinforcing, wherein the depth of the bamboo tube sections in the ground is 400mm, the depth of the leading holes is slightly less than 400mm, the bamboo tube sections can be conveniently driven into the stratum by sharpening one end of each bamboo tube section, the transverse distance of the bamboo tube sections is 700mm within the range that the excavation step part is transversely prolonged by 1000mm, the longitudinal and transverse distances of the bamboo tube sections of the rest filling parts are 1000mm, the bamboo tube sections are arranged between the upper filling layer and the lower filling layer in a crossed mode, and the transverse distance of the A-shaped bamboo tube sections arranged at the base is 700mm and the longitudinal distance of the A-shaped bamboo tube sections is 1000 mm.
And ④, horizontally reinforcing the bamboo ribs, horizontally paving the bamboo ribs above the compacted filling layer along the transverse direction and the longitudinal direction, fixedly connecting the bamboo ribs and the A-shaped bamboo tube sections by using steel wires to form a rectangular bamboo rib grid, wherein the bamboo rib grid is tightly attached to the compacted filling layer as shown in figure 5, the strip bamboo ribs with insufficient length can be spliced with each other, the spliced parts are firmly bound by the steel wires, the superposition length of the two strip bamboo ribs is not less than 100mm, and further, diagonal bamboo ribs can be properly arranged within 2000mm of the filling interface for reinforcement.
Bamboo muscle level is strengthened muscle and is connected vertical thick bamboo tube crowd as a whole, has effectively increased the intensity and the steadiness of whole muscle system that adds, and the bamboo muscle graticule mesh that fixed connection formed between bamboo muscle and thick bamboo tube is similar with conventional "geogrid" reinforcement mode in certain meaning, has effectively prevented the inhomogeneous settlement of road bed, avoids the road bed filling layer to slide, and traditional geogrid is compared to the mode that the bamboo timber adds the muscle, and its material is more green, the cost is lower, it is better to add the muscle effect.
And ⑤, performing roadbed filling, vertical reinforcement, filling and compaction on a single layer of the embankment, and further performing upward construction layer by layer, wherein the filling height of each layer of the same material is not less than 500mm, different filling materials need to be layered, the roadbed filling adopts a transverse segmentation and vertical layering mode to perform upward layer by layer from the lowest part, and the same layer adopts a mode of filling from two sides to the middle.
And ⑥, leveling and rolling, primarily leveling the newly-filled layer to ensure that the layer surface has no obvious local concave-convex, layering and compacting in sections along the longitudinal direction of the line to finish the construction of the newly-filled layer, and then repeating the step ② to carry out the construction of the next layer until the height of the top surface of the roadbed.
Example 4:
for roadbed filling under IV-class working conditions, as shown in FIG. 6:
foundation treatment step ① roadbed filling is performed by first removing the turf, humus, etc. of the foundation and then appropriate roughening treatment is performed on the foundation.
And ②, excavating slope steps, excavating the steps at the interface of the filling section, wherein the transverse length of the steps is not less than 2000mm, the vertical height of the steps is not more than 3000mm, and the upper step and the lower step are continuous.
③, vertically reinforcing the bamboo tube, leading holes in the compacted filling layer and driving B-shaped bamboo tube sections, as shown in figure 2, vertically reinforcing the bamboo tube sections, wherein the ground penetration depth of the bamboo tube sections is 400mm, the leading hole depth is slightly less than 400mm, and the sharpening treatment of one end of the bamboo tube sections can facilitate the bamboo tube sections to be driven into the stratum;
step ④, horizontally reinforcing the bamboo ribs, horizontally paving the bamboo ribs above the compacted filling layer along the transverse direction and the longitudinal direction, and fixedly connecting the bamboo ribs and the B-shaped bamboo tube sections by using steel wires to form a rectangular bamboo rib grid, wherein the bamboo rib grid is tightly attached to the compacted filling layer;
and ⑤, grouting the bamboo tube, connecting one end of a high-pressure pipe with a high-pressure grouting pump, connecting the other end of the high-pressure pipe with a grouting opening of the bamboo tube, starting the high-pressure grouting pump to press cement grout into the cavity of the bamboo tube, stopping grouting and stabilizing pressure for five minutes when the grouting cement amount reaches the position of a grouting hole of the bamboo tube, namely the grouting height is more than 300mm, or the surface of the bamboo tube is raised or seeped, pulling out the high-pressure pipe, sealing the cavity of the bamboo tube after grouting, and further arranging a small number of grouting holes in the B-shaped bamboo tube section implanted into the original slope body part and the base part so that more cement grout flows into the original slope body part through the grouting holes in the cavity of the bamboo tube after grouting, wherein the original slope body part and the base part are dense grouting sections, and other roadbed filling parts are thin grouting sections.
The cement slurry of the close-grouting section cements the original slope body, the base material and the filling material into a whole, so that the integral stability degree of the original broken slope body, the original weak roadbed or the original expansive soil roadbed such as the rice field and the like is effectively improved, and the strength of the filling roadbed is improved; the cement slurry of the diluted injection section can effectively stabilize the position of the bamboo tube section in the stratum, so that a stable pile pier is formed around the bamboo tube section, the bearing capacity of the roadbed is improved, and slippage and uneven settlement at an interface are effectively prevented; the targeted grouting technology effectively prevents the waste of grout and has pertinence to the reinforcement treatment of the roadbed;
step ⑥, roadbed filling, vertical reinforcement, filling and compaction are carried out on single layer of the embankment, and then upward construction is carried out layer by layer, the filling height of each layer of the same material is not less than 500mm, layering is needed among different filling materials, roadbed filling is carried out layer by layer from the lowest position upward by adopting a transverse segmentation and vertical layering mode, and construction is carried out on the same layer from two sides to the middle
And ⑦, leveling and rolling, primarily leveling the newly-filled layer to ensure that the layer surface has no obvious local concave-convex, layering and compacting in sections along the longitudinal direction of the line to finish the construction of the newly-filled layer, and then repeating the step ② to carry out the construction of the next layer until the height of the top surface of the roadbed.
The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention.