CN210712595U

CN210712595U - Cement member crossing road

Info

Publication number: CN210712595U
Application number: CN201921304035.9U
Authority: CN
Inventors: 贾殿录
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-08-13
Filing date: 2019-08-13
Publication date: 2020-06-09
Anticipated expiration: 2029-08-13

Abstract

Across the road cement structure. At present, when the traditional cast-in-place construction mode is adopted, the construction process is complicated, the construction site requirement is high, the construction period is long, and the maintenance cost is high. The cross road cement member comprises the following components: assembled box culvert (1), processing of assembled box culvert top mould port has protruding slot (2), processing of bottom port department of assembled box culvert has protruding draw-in groove (3) that have annular opening, and insert protruding draw-in groove in the protruding slot on another assembled box culvert, and the four corners setting in protruding slot is used for forming PE pipe (4) in prestressing tendons pore, the pre-buried four corners position department in assembled box culvert top of PE pipe straight line, then pore (5) are reserved in the four corners of the coupling of PE pipe, wear steel strand wires in the pore, stretch-draw, carry out seam treatment and pore grout after the stretch-draw is accomplished, then carry out wing wall and handle the side backfill of culvert. The utility model discloses be applied to road construction field.

Description

Cement member crossing road

The technical field is as follows:

the utility model relates to a cross highway cement component.

Background art:

the snow municipal engineering Limited liability company in seven rivers establishes a ' Brand of province, the same river and the same river to Wang Qing highway, Brilliant to Brilliant junior, the construction government and the social capital cooperation (PPP) mode, the project comprises two sub-projects of a ' Bollidon export to south export first-level road section (K367 +200-K374+456) ' and a ' Bollinan export to Bolliant junior second-level road section (K374 +456-K390+ 134) ', the planned cooperation period is temporarily set to be 17 years (including a construction period of 2 years and an operation period of 15 years), and the project is started and constructed in 2018 years. The section from the export of the Boleinan to the Secondary road section (K374 +456-K390+ 134) of the Bolilin boundary section is reconstructed from an old road, the main engineering content comprises 280.12 long meters/20 channels of reconstructed and expanded culverts, wherein 8 channels of 3.0 multiplied by 2.0m box culverts and 12 channels of 1.5 multiplied by 1.25m box culverts, the original design scheme adopts a cast-in-place mode for construction, and when the cast-in-place mode is adopted for construction, the construction process is complicated, the requirement on the construction site is high, the construction period is short, and the maintenance cost is high.

According to the contract of the project government and the social capital cooperation (PPP) mode of reconstruction and extension in the section from Boliqing to Wangqing highways from the same river to the same river of province, the project planning period is 2 years and is short. After the project manager enters the construction site, when a construction scheme of a second-level road section is formulated, the construction of the section is found to be the transformation of an old road, the construction needs to be carried out while the vehicle is turned on, the number of culverts in the section is large, one road is prolonged by 150 meters on average, the required working face is large, if the construction is carried out in a cast-in-place mode according to the original design, the time of dragging the road surface is long, and great inconvenience is brought to the trip of villagers along the line. Through investigation, local villagers adopt a motorcycle mode to travel more, often carry cargo and carry people, according to the construction experience of the conventional cast-in-place culvert, the villagers sometimes fall into the pit slot due to the fact that the road conditions of the construction sidewalks are not mature or the marks are not observed carelessly, personal damage and economic loss are caused, disputes often occur with construction units, manpower and material resources of the construction units are greatly wasted, and great potential safety hazards exist.

The invention content is as follows:

the utility model aims at providing a cross highway cement component.

The above purpose is realized by the following technical scheme:

a cross-road cementitious structure comprising: assembled box culvert, assembled box culvert top mould port processing have protruding slot, the bottom port department processing of assembled box culvert have the protruding draw-in groove that has annular opening, and will protruding draw-in groove insert another assembled box culvert on in the protruding slot, and the four corners setting of protruding slot be used for forming the PE pipe in prestressing tendons pore, PE pipe straight line pre-buried be in assembled box culvert top four corners position department, then the four corners of the tube coupling of PE pipe reserve the pore, wear steel strand wires in the pore, carry out the stretch-draw, carry out seam treatment and pore stretch-draw grout after the completion, then carry out wing wall and handle the backfill of culvert side.

The cross highway cement component, assembled box culvert adopt the mould molding, assembled box culvert include that reinforced concrete culvert body, prestressing steel strand wires, wing wall, basis, movement joint, assembled box culvert's culvert body be by the nonstandard festival and standard culvert the whole closed reinforced concrete frame structure that the festival combination formed, wherein two assembled box culvert butt joint through the socket joint mode, assembled box culvert on seted up the grout pore.

The transverse road cement component is characterized in that when the assembly box culvert is of a rectangular structure, an upper lifting ring and a lower lifting ring are symmetrically arranged on two sides of a short side of the assembly box culvert, and the upper lifting ring and the lower lifting ring are of a structure perpendicular to each other by 90 degrees.

The utility model has the advantages that:

1. the utility model discloses can overcome the defect of cast-in-place box culvert technology, adopt prefabricated site prefabricated box culvert pipe coupling, hoist and mount to the job site installation back, use steel strand wires to carry out stretch-draw fixed. The box culvert is composed of a reinforced concrete culvert body, prestressed steel strands, wing walls, a foundation and deformation joints, and the box culvert body is an integrally closed reinforced concrete frame structure formed by combining nonstandard culvert sections and standard culvert sections. Under the prerequisite of guaranteeing the culvert quality, can carry out mass production, on-the-spot assembly, a large amount of road surface fluting's time that has reduced for the culvert construction progress, shortened construction cycle, effectively avoided construction potential safety hazard. The problems that the construction period of a cast-in-place culvert is long and the quality of an assembled culvert is difficult to control in the conventional highway construction are solved.

2. The utility model discloses at first prefabricate box culvert pipe coupling in prefabricated place, the box transports through the butt joint of socket joint mode to construction site back, then wears steel strand wires in the pore that the pipe coupling four corners was reserved, carries out stretch-draw, carries out seam processing and pore grout after the stretch-draw is accomplished, then carries out wing wall and handles the side of culvert and backfill. The process enables each sectional assembly type box body to be a whole and has certain prestress, thereby greatly improving the integrity and the bearing capacity of each box body and achieving or even exceeding the strength of a cast-in-place box body.

3. The utility model adopts the construction method to avoid the defects of large working surface and long construction and maintenance time in the construction of cast-in-place box culvert, effectively saves time and cost, and avoids other hidden expenses; meanwhile, the problems that a common assembly type box culvert cannot form a whole and pipe joints are not uniformly settled are solved. The process is used for box culvert construction, the time for opening the working face is greatly shortened, the next procedure can be quickly carried out, the construction investment is increased less, the manpower and the later maintenance cost are greatly saved, and the engineering quality is ensured. The construction period dragging condition caused by construction factors such as limited site and damaged environment is improved, the construction task is ensured to be completed within the contract construction period, the construction progress of the project which does not meet the construction conditions due to external factors and is short in construction period is solved more properly, and the social benefit is remarkable.

4. The utility model overcomes ordinary assembled box culvert segmentation tube coupling can not effectively link up, appears the tube coupling dislocation easily, seam warp, the not strong scheduling problem of wholeness, and this technology will respectively segment the box through steel strand wires and connect into a whole, applys certain prestressing force simultaneously, very big improvement the wholeness and the bearing capacity of each box, reach the intensity that surpasss cast-in-place box even.

5. The utility model discloses the construction is simple and convenient:

(1) the prefabrication of the components is not restricted by weather and can be completed in the best time period as much as possible. The construction organization plan is completed on time to be guaranteed.

(2) The structural design can be accurately carried out, and the designed product can be accurately realized. The consumption of steel, cement and other materials can be controlled.

(3) The structure construction becomes very easy, just like "assembling building blocks". The process is simplified, the construction is safe, and the work point is clean.

(4) Because the component is designed to be self-stable, a large amount of supports and scaffolds are not needed. The amount of temporary engineering material used is correspondingly reduced.

(5) The technical characteristics of each work point are outstanding, the construction equipment is centralized, the high efficiency of the work and the continuity of the quality control are ensured, and the technical consumption on some fine levels is not needed.

(6) The technical and quality advantages enable the problems of stability, corrosion resistance, leakage prevention and the like of the structure to be reduced, and meanwhile, the maintenance consumption of the structure is reduced to the maximum extent.

(7) The prestress assembly type box culvert has good integrity and earthquake resistance, can adapt to culverts with various spans, is made into a multi-box form according to the length of the culvert and is easy to build.

The construction period is short:

the prestress assembly type box culvert can be produced in batches, is quick to install, and can save about 1 month in the construction period.

The economic benefit is better:

if a new mixing site is built and supporting equipment materials are purchased at one time, the construction investment of the prestress assembly box culvert is slightly higher than that of a cast-in-place box culvert, and is increased by about 10 percent; if the mixing station and the turnover equipment are made of materials owned by construction units, the process can greatly save the labor cost in the construction period, shorten the construction period, avoid hidden expenses such as safety accidents and the like, reduce the cost of the whole life cycle and has higher comprehensive economic benefit.

The safety is high:

by adopting the process, the road slotting time is greatly shortened, the probability of safety accidents is effectively avoided, meanwhile, the investment of personnel in site construction is reduced, and the construction safety is improved.

The technology applies 'new technology, new equipment, new material and new technology' with high efficiency and high level as principle. The advanced scientific and technological achievements are actively applied, and the mechanized operation level of construction is improved, so that the box culvert construction can be finished with high quality, rapidness, safety and high efficiency. Is a process which is beneficial to the nation and the people and is worthy of deep research and wide popularization.

Description of the drawings:

fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a top view of fig. 1.

Fig. 3 is a left side view of fig. 1.

Fig. 4 is a bottom view of fig. 1.

Fig. 5 is a sectional view a-a of fig. 2.

Figure 6 is a schematic diagram of the square structure of the fabricated box culvert.

Fig. 7 is a top view of fig. 6.

In the figure, the prefabricated box culvert comprises 1, 2, a convex slot, 3, a convex clamping groove, 4, a PE pipe, 5, a reserved hole channel, 6, a grouting hole channel, 7, an upper hanging ring, 8 and a lower hanging ring.

The specific implementation mode is as follows:

example 1:

the cross-road cementitious structure of embodiment 1, comprising: assembled box culvert 1, assembled box culvert top mould port processing have protruding slot 2, the bottom port department processing of assembled box culvert have the protruding draw-in groove 3 that has annular opening, and will protruding draw-in groove insert another assembled box culvert on in the protruding slot, and the four corners setting of protruding slot be used for forming the PE pipe 4 in prestressing tendons pore, PE pipe straight line pre-buried the four corners position department of assembled box culvert top, then the four corners of the tube coupling of PE pipe reserve pore 5, wear steel strand wires in the pore, carry out the tensioning and carry out the seam processing and pore grout after the tensioning is accomplished, then carry out wing wall processing and contain the side backfill.

Example 2:

according to embodiment 1 the crossing highway cement component, assembled box culvert adopt the mould molding, assembled box culvert constitute by reinforced concrete culvert body, prestressing steel strand wires, wing wall, basis, movement joint, assembled box culvert's culvert body be by the non-standard culvert festival with standard culvert festival combination form whole closed reinforced concrete frame structure, wherein two assembled box culvert butt joint through the socket joint mode, assembled box culvert on seted up grout pore 6.

Example 3:

according to

embodiment

1 or 2, when the assembly box culvert is in a rectangular structure, the upper lifting ring 7 and the lower lifting ring 8 are symmetrically arranged on two sides of the short side of the assembly box culvert, and the upper lifting ring and the lower lifting ring are in a structure perpendicular to each other by 90 degrees.

Example 4:

(1) preparation for construction

According to the construction requirements, temporary construction facilities are set up, and mechanical equipment and personnel are organized to enter the field.

And organizing technicians to learn and understand design drawings and recheck the structural size, the specification size of the steel bars, the engineering quantity and the like of the assembled box culvert.

And (3) testing various raw materials and steel bar welding joints entering a field, performing concrete trial, optimizing the mix proportion and reporting to a supervision engineer for approval. And prefabricating protective layer mortar cushion blocks of the same concrete label.

Processing and manufacturing of steel bar

The steel reinforcement framework of the prefabricated part is processed in batch after being molded, and the processing technology meets the requirements of JTG/TF50-2011 Highway bridge and culvert construction technical specification. And welding and assembling the forming die of the steel bar framework according to the size given by the drawing, and directly finishing the processing of the semi-finished product of the framework on the forming die. The longitudinal and transverse ribs, the stirrups and the vertical ribs of the framework are connected by spot welding.

(1) Processing technology of steel bar

① the specification, grade and steel grade of the steel bar meet the requirements of design drawings and technical specifications;

② cleaning the surface of the steel bar, and removing oil stain and paint coat before use;

③ straightening the steel bar before use without local bending, and straightening the coiled steel bar and the bent steel bar by a straightener;

④ steel bar skeleton installation, the reinforced concrete protective layer thickness accords with the design requirement, in order to control beam slab protective layer qualification rate, my project department introduction concrete cushion equipment, satisfy the design requirement with control concrete protective layer thickness, improve the protective layer qualification rate, cushion intensity C50, the cushion is laid firmly, it is inseparable with the reinforcing bar contact, phenomenons such as unsettled rake angle do not, fix with double-deck ligature silk, guarantee that the cushion does not take place the aversion at the concrete placement in-process of vibrating, and the ligature silk head is uniformly buckled to the reinforcing bar inboard, uniformly can not get into in the protective layer.

(2) The processing method of the steel bar comprises the following steps:

① derusting steel bars, if the steel bars are rusted before use, the artificial derusting is mainly adopted, i.e. floating skin, rust and oil stain are removed by using tools such as a wire brush, a sand disc and the like.

② the steel bar is processed by newly purchased WG120D-2 numerical control steel bar hoop bending machine, YFH-32 type numerical control steel bar bending center and XQ120 numerical control bar shearing production line, three sets of numerical control steel bar processing equipment can meet the requirements of various stirrup specifications of drawings, and ensure the geometric dimension of the steel bar and control the processing quality of the steel bar.

③ welding steel bars, wherein the welding steel bars adopt a double-sided welding mode, and the length of the lap joint double-sided welding seam is not less than 5 cm.

Template manufacturing and assembling:

(1) requirements of formwork construction process

① the engineering adopts large steel templates;

② the basic requirements of template installation are that the surfaces of the template are flat, the wiring is tight, the grout does not leak, the exposed surface of the structure is beautiful, and the lines are smooth;

③, the template installation is matched with the steel bar installation work, and the template influencing the steel bar installation is installed after the steel bar installation;

④ after the template is installed, checking the plane position, top elevation, node connection and longitudinal and transverse stability of the template;

⑤ when the concrete strength of the box culvert reaches 50% of the design strength, and the form can be removed when the corner of the component is complete, when the form is removed, the form is prohibited to be hit or pried, avoiding causing the form to deform locally or damage the corner of the concrete.

(2) The template is a steel template processed in a factory. Assembling on site, wherein each surface is an integral steel die, and special treatment is carried out on the surface to meet the requirement of smoothness; the strip line is adjusted to be linear after the integral installation, so that the geometric dimension of the component is met; the template seam is specially treated, and the water is stopped by the soft foam for the template seam, so that the slurry leakage is prevented, and the seam flatness is ensured.

The template is polished and cleaned before being erected, a release agent is coated, the formwork erection is carried out according to a control line, after the template is installed, field technicians carry out self-inspection on the stability, the screw spacing, the geometric dimension, the abutted seam, the connection firmness and the like of the template, and written records are made. And the flatness of the joint is ensured; and (3) coating a release agent on the surface of the template to ensure smooth release. The template needs to be straight, the corner needs to be smooth, the welding line needs to be smooth, and the welding line needs to be polished and ground; the dispatching of the template bolt holes is accurate, when the template is assembled, the relative position is accurate, and the welding seam is smooth; the corner template and the bottom die are required to be flat, and the positions of the reserved holes are required to be accurate.

(3) Form assembly

Basic requirements for template installation: the surface of the plate is flat, the wiring is tight, the grout does not leak, the appearance of the exposed surface of the structure is ensured to be attractive, the lines are smooth, and the plate separation seams are not treated by adopting foaming agents. And after the template is installed, checking the plane position, the node relation and the longitudinal and transverse stability of the template.

The installation of the template is matched with the operation of the steel bars, and the template which obstructs the binding of the steel bars is installed after the steel bars are installed. Generally, the bottom die is flat, the inner die and the outer die are installed after the reinforcement cage is installed, the inner die and the outer die can be installed at first, and in addition, the deformation of the template caused by manual operation needs to be prevented.

The precision of the formwork installation is higher than the precision requirement of the prefabricated parts. After the template is installed, the next procedure can be performed after the template is qualified through inspection and acceptance. The precision requirement of the template needs to meet the relevant regulations in construction specifications and drawing descriptions. In order to protect the template to be convenient to disassemble, the contact surface of the template and the concrete, the contact surface of the integrally moving inner mold and the outer mold and the concrete are coated with salad oil or special release agent and other treatment measures before use.

The entrance template is a large steel mould, the bottom mould is directly placed on the hardened and leveled place in a pier mode, and the top mould is composed of sectional shaped steel mould cover plates. When the template is assembled, the two sides are symmetrically assembled from the middle.

Stirring, transporting, vibrating and curing the concrete:

according to the construction quantity and the construction characteristics of the components, a mixing site is built and 2 sets of HZS120 type mixing stations are equipped.

(1) Before concrete is mixed, a mixing station and various metering devices are installed, debugged and calibrated to ensure accurate metering;

(2) measuring the water content of various aggregates and adjusting the construction mixing proportion;

(3) the sufficient time for concrete mixing is ensured, the uniform mixing and the consistent color of the concrete mixture are ensured, and the phenomena of segregation and bleeding are avoided;

(4) concrete transportation is carried out by adopting a concrete tank truck, and the transportation capacity needs to adapt to the requirements of the concrete setting speed and the pouring speed. (5) Arranging PE pipes for forming prestressed tendon ducts at four corners of the box culvert;

(6) technical requirements for concrete placement

① checking the uniformity and slump of the concrete before pouring, and preventing the concrete from separating when pouring from high place;

②, pouring concrete layer by layer along the direction with the thickness of 30cm, wherein the concrete pouring is continuously carried out, and the interruption time is less than the initial setting time of the front layer concrete if the concrete pouring is interrupted for reasons;

③ it is tamped by inserted vibrating rod whose moving distance is not more than 1.5 times of its radius, and it is inserted into the concrete in lower layer by 50-100 mm while keeping a distance of 50-100 mm from side mould, and the vibrating rod is pulled out slowly after each position is vibrated.

(7) Stacking and curing finished components:

finished product component handling is to component storage area, and the component horizontal spacing is 0.5m, and the finished product component is stacked and is adopted artifical watering health preserving in storage area, and every batch of component guarantees to be no less than 7 d's health preserving time.

(8) Demolding and marking:

the quality of the form removal relates to the quality of the prefabricated part and the turnover use of the form. The non-bearing side template can be disassembled when the strength of concrete can ensure that the surface and edges and corners of the non-bearing side template are not damaged due to template removal, and the side template can be disassembled when the compressive strength of the concrete reaches 2.5MPa generally. And (5) hanging and moving for storage. After the template leaves the member, the template still needs to be moved out of a certain gap more and then lifted, so that the member and the template are prevented from colliding during lifting, and then the template is lifted to a storage place for cleaning, maintenance, oiling and maintenance for next use.

After demolding is completed, the number is marked for installation.

Excavation and inspection of a foundation pit:

(1) the foundation pit is excavated by manually matching an excavator, and 10cm of pit bottom is reserved for manually cleaning and leveling the bottom. Excavating according to the design size and the excavating depth and according to the following steps of 1: a width of 0.75 relief and a base reserve working width (0.5 m per side). The reserved working width of 0.5m outside the foundation size of the foundation pit is used as a water collecting well, a drainage ditch land and a reserved construction operation space so as to ensure that the foundation soil is not soaked by water and facilitate the hoisting of the template and the prefabricated part.

(2) Excavation foundation pit soil is stacked and a guard way with the width not less than 1m is reserved on the top edge of the pit, the construction sidewalk and the position of a hoisting platform planned in advance are avoided, a special person is required to command the excavation site, the slope rate and the pit wall safety are checked while excavation is carried out, excavated soil cannot be stacked at will, the foundation pit soil is not suitable for filling, is cleaned and discharged, and is loaded to a nearby spoil yard by a dumper in time for uniform stacking, so that excavation of the foundation pit and other operations are not influenced.

(3) After the foundation pit is excavated, the periphery of the top of the pit is timely surrounded and blocked, and when the depth of the foundation pit exceeds more than 2m, a crawling ladder for people to go up and down is arranged in the pit.

(4) The plane position, the geometric dimension, the elevation and the bearing capacity of the base are required to be reported and tested immediately after the foundation pit is dug to the designed elevation, and cushion layer construction is required to be carried out in time after the requirement is met, so that the exposure time of the foundation pit is prevented from being overlong.

Gravel cushion layer:

setting a thickness scale of the backfill sand layer, and controlling the thickness of each blank sand layer within 30 cm. Selecting medium coarse sand with reasonable gradation and extremely small mud content, and adopting mechanical transportation, artificial backfilling and leveling. After the sand of the first blank layer is backfilled, a proper amount of clean water is injected immediately, and the water level is controlled to be slightly higher than the surface layer of the backfilled sand. After the water is injected, inserting and vibrating are sequentially carried out by adopting an inserting type vibrator according to the distance between the diagonal lines not exceeding 30cm, and the vibrating time is not less than 40 s. After the backfilled sand is completely shocked by water, a pump is started to pump water in time, and a flat vibrator is used for vibrating in a criss-cross mode to be compact during water drainage until the water is dry.

Concrete foundation:

(1) the mode of assembling by adopting a common plane steel die is adopted, the thickness of the plane steel die panel is 5mm, and the assembling is realized by adopting M16 bolt connection. Because the thickness of the concrete base layer is 10cm, the template with the height of only 30cm is adopted, and only manual assembly is needed. Before the template is installed, polishing and derusting are carried out, and a contact surface of the template and concrete is coated with a release agent.

(2) After the template and the support are firmly reinforced, the abutted seams of the template are checked, the number and fastening degree of connecting pieces and screws are checked, the firmness degree of a support system is checked, the surface flatness, the inner side line straightness and the inner size of the template are checked, and concrete can be poured after the design and specification requirements are met and the approval of a supervision engineer is reported.

(3) Pouring of concrete

① concrete pouring adopts mixing station centralized mixing and concrete tank truck transportation, before the concrete leaves factory, the slump test is carried out by a laboratory and a supervision engineer together, the workability of the concrete is checked, and the concrete can be used only after the test result meets the standard requirement.

② after the concrete is transported to the site, the concrete is poured by a crane and a whole hopper, the distance between the discharge port and the pouring surface is controlled within 2m when the concrete is poured, so as to prevent the concrete from separating, when the height of the pouring exceeds 2m, a string cylinder is arranged, the concrete is vibrated by a 50-type plug-in vibrator, the distance of l00mm is kept between the vibrator and the side mold when the vibrator is vibrated, the moving radius of a vibrating rod is controlled according to 35cm, the vibrator must vibrate until the concrete at the position is compact, the compact mark is that the concrete stops sinking, no air bubble is generated, the surface is flat and starching, during the concrete pouring, a specially-assigned person is arranged to check the stability of the support and the template, and when the looseness, the deformation and the displacement are found, the treatment is carried out in time.

③ the concrete of the hole body is poured, vibrated and compacted and then leveled by a 3m ruler, the levelness of the cross section direction is checked by a level ruler, the levelness still needs to be checked again when the hole body is subjected to secondary slurry collection, the elevation error is controlled within 10mm, and the leveling bottom is controlled within 3 mm.

(4) Maintenance and form removal

① after the concrete is finally solidified, covering with geotextile, sprinkling water and preserving for at least 7 days, and dispatching a specially-assigned person for sprinkling water and preserving for at least 7 days, wherein the sprinkling time is determined by keeping the surface of the concrete in a wet state frequently.

② when the strength of the concrete reaches 2.5Mpa, the form can be removed, the construction process should be specially careful not to generate impact on the concrete surface to avoid damaging the concrete corners, the removal of the form is not allowed to be done by violent hammering and strong twisting, the form is strictly forbidden to be thrown away when being removed, after the form and the support are removed, the surface mortar and dirt of the form should be cleaned, maintained, sorted and stored properly for the next use.

Hoisting and transporting the box culvert:

(1) the quality of the culvert sections is checked and accepted in a prefabricated site before hoisting the culvert sections. And checking whether the inner and outer diameter sizes and the thickness are consistent with the design drawing, and whether the overall deformation condition, the appearance and the defect repair condition of the culvert section are within the specified range.

(2) And (5) detecting the strength of the concrete. And (3) carrying out rebound mixing detection on box culverts which are not aged in a laboratory, and hoisting the box culverts when the strength of the concrete reaches 100% of the designed strength.

(3) And (5) identifying culvert sections. And marking the dimensions, specifications, casting date, culvert mileage and box culvert number on culvert sections.

(4) And when the strength of the concrete reaches 100% of the designed strength, carrying out hoisting transportation according to the box culvert number and the installation sequence.

(5) And hoisting (manually matching) the culvert sections by using a truck crane, and transporting the culvert sections to a construction site by using a transport vehicle. The corner protectors are adopted to protect the corners of the box culvert before the box culvert is lifted, when the lifting starts, the box culvert is slowly stressed to be lifted to a transport vehicle at normal speed after being lifted off the ground stably, and sleepers are added to the transport vehicle for supporting. After the culvert sections fall down, the culvert sections are pulled and fixed by steel wire ropes, and the contact friction positions are protected by adding pads to prevent the culvert sections from being damaged in the transportation process.

And (3) box culvert installation:

(1) before assembly, the components should be placed at designated positions, the operation positions of equipment such as a crane and the like, and the material, equipment access routes and the like should be properly arranged in advance.

(2) The structural members are trial-assembled before assembly, and the structural stability and positioning adjustment implementation scheme of the system is provided.

(3) The installation sequence is from high to low, and if necessary, the support rod and the steel wire rope can be used for assisting the stabilization. Collision should be avoided during assembly, and the damaged component should be evaluated, repaired in time, and replaced if necessary. The order and location of the placement of the components and segments must not be confused.

(4) Before the box culvert is installed, the contact surface is cleaned, and meanwhile, the box culvert is subjected to transverse and longitudinal lofting on the basis of the culvert. Leveling is carried out on the surface of the culvert foundation during installation, and the box culvert is hung to the specified position of the culvert foundation by a crane. When in place, the positions of the box culvert sections are controlled by adopting culvert axis hanging lines.

(5) When the box culvert is installed, the staggered platforms of culvert sections are accurately controlled, and particularly the staggered platforms of the top surface and the two side surfaces of the box culvert are controlled after the box culvert is in place.

(6) And (5) washing and wetting the concrete surfaces on two sides of the construction joint, filling small broken stones in the joint between the joints and filling cement mortar. The outer side is filled with asphalt floc, and the construction of the water stop belt is carried out by an outer wrapping method.

(7) The inner side of the settlement joint hole body is filled with cement mortar, the filling depth is 15cm, and clay is filled in the middle. The outer side is filled with asphalt floc, and the construction of the water stop belt is carried out by an outer wrapping method.

(8) The inner side of the joint is pointing by mortar, and the width of the joint is 5 cm. The thickness is uniform, and the straight and beautiful appearance of the inner side line of the box culvert is ensured. In order to ensure the firm connection between the mortar and the box culvert, the mortar is recommended to be mixed with glue.

Pre-stress tension:

the prestress tension process flow comprises the following steps: the method comprises the steps of steel strand threading → installation of a working anchor → installation of a matched limiting plate → installation of a jack → installation of a matched tool anchor → two ends of symmetrical tensioning → tensile force of 15% → tensile force of 30% → tensile force of 100% → tensile force of 103% → load holding 2min anchoring → correction, and after the elongation value is qualified, next tensioning → tensioning operation is finished. During tensioning, the following matters need to be taken into consideration:

(1) before tensioning, carefully checking whether the steel strand, the anchorage device and the anchor backing plate are damaged or not, and whether the anchor backing plate is inclined or not, if so, timely adjusting the steel strand, the anchorage device and the anchor backing plate in place, and then tensioning.

(2) An obvious mark is set on the construction site, and necessary safety protection measures are made. During tensioning, people are prohibited from standing behind the jack.

(3) The operators in the tensioning class should be familiar with the tensioning process, and strictly and rigorously treat each procedure in the construction, so that the operators cannot get the tiger half-way, and need to carry out safety technology training before tensioning.

(4) Each batch of the incoming materials is subjected to sampling inspection according to the batch number, and can be put into use after being detected to be qualified, the materials such as the steel strand, the anchorage device, the PE pipe and the like are kept and stored properly, and are rain-proof and waterproof, and the PE pipe is prevented from being bent.

(5) Pulling-through bundle

① the steel strand is fed according to the designed length plus the length of the tension device, and the rest is fed with the total length of no less than 100mm outside the anchor, the feeding is cut flatly by a grinder, and the cut steel strand is laid on the ground, and measures are taken to prevent the steel strand from loosing ends.

② the steel strands are cut and then arranged in order according to each bundle, and the bundle penetrating through the same pore passage is suitable for the whole bundle penetrating.

③ the tying can be done manually or mechanically, and the tying head should be smooth to prevent wall breakage.

(6) Pre-stress tension:

① cleaning the concrete in the anchor backing plate, and checking whether the grouting holes of the anchor backing plate are blocked.

② remove rust and mud on the steel strand.

③ checking if there is any slurry leakage in the prestressed duct and if necessary, removing it.

④ installing the working anchor plate, the anchor plate should be aligned with the front edge of the anchor backing plate.

⑤ A working clip is mounted in each tapered hole of the working anchor plate and is flush after mounting, and the clip is tapped by a special tool if necessary but is not damaged by tapping.

⑥ the tensioning jack is installed to connect it with high-pressure oil pump.

⑦ a jack is used to stretch the prestressed tendon, the stretching sequence is symmetrical from outside to inside, the prestressed tendon is pre-stressed by double control measures, the stress value is mainly read by an oil pressure gauge, and the elongation value of the prestressed tendon is checked.

Grouting the pore channel:

(1) and (4) cleaning the grouting hole channel by pressing water, checking whether the grouting hole and the air outlet are communicated with the prestressed tendon hole channel, and otherwise, processing in advance.

(2) After the prestressed tendon is tensioned, the hole grouting is carried out as early as possible to reduce the loss of prestress.

(3) The grouting pressure is generally 0.4 to 0.6 MPa.

(4) The grouting sequence is that the lower layer of pore canal is stopped by slurry leakage of the upper layer of pore canal, the lower layer of pore canal is stopped after thick slurry is discharged from the exhaust hole, the exhaust hole is stopped, the slurry is pressed to 0.6MPa, and the grouting hole can be stopped after the thick slurry is kept for l-2 min.

(5) And (5) making a test block and paying attention to maintenance.

(6) Pouring end-sealed concrete or performing end protection treatment, and paying attention to concrete curing;

sealing an anchor:

the end beam sealing anchor is finished before hoisting. When the anchor is sealed, a shaped steel template is required to be adopted for supporting, and concrete vibration is enhanced. And when the anchor is sealed, the length of the beam plate is strictly controlled. The position, the height and the angle of the embedded steel bars of the expansion joint of the end beam meet the design requirements, and the expansion joint and the embedded steel bars are ensured to be well connected; the template is firmly supported without deformation and running; otherwise, the process must be reworked.

Backfilling the culvert side:

The prestress assembly type box culvert construction key points are as follows:

processing and installing steel bars:

the numerical control bending machine is adopted in the processing of the reinforcing steel bars, the accuracy of the size of the reinforcing steel bars is ensured, binding and forming are carried out by adopting a positioning frame, and the reinforcing steel bars are installed in an integral hoisting mode after forming. The position of the structural steel bar is accurately marked on the positioning frame, so that the accuracy of the installation position of the steel bar is ensured, and the steel bar loss is avoided. When the steel reinforcement framework is installed, a gantry crane or a truck crane is adopted to hoist and enter the die at one time, and the reinforcement of a hoisting point and the control of the position of the hoisting point are noticed in the hoisting process, so that the deformation of the steel reinforcement framework is prevented.

The crossing point of the reinforcing steel bar is bound firmly by using an iron wire and is firmly welded by spot welding if necessary. The wire heads of the iron wires for binding are bent inwards and cannot extend into the concrete protective layer.

And (3) template manufacturing and installation:

the template is an integral steel mold which has enough strength, rigidity and stability and can bear various loads generated in the construction process. The back of the template is provided with a main rib and a secondary rib which are used as supporting beams, so that the integral rigidity of the template is enhanced. The thickness of the template is not less than 6 mm.

Concrete construction:

before the concrete is prepared and mixed, all mechanical equipment, tools and used materials are carefully checked, and the normal and continuous operation of mixing and pouring of the concrete is ensured.

The concrete mixture batching adopts automatic metering device, and the measurement should be accurate. In order to control the metering error, a black box is arranged for supervision. Measuring the water content of the coarse aggregate and the fine aggregate before opening the tray, and simultaneously adjusting the water consumption, the use amount of the coarse aggregate and the use amount of the fine aggregate according to the actual measured value; and (5) adding water after the concrete is forbidden to leave the machine.

The concrete is intensively mixed and transported by a concrete tank truck. Stirring at a slow speed of 2-4 r/min during transportation, and stirring at a constant speed before discharging. The concrete is poured continuously and formed in one step, and the pouring time is not longer than 3 h. And selecting a reasonable vibrating radius, improving the vibration frequency, controlling the vibrating radius to be 45-75 cm, controlling the insertion distance to be less than 60cm, and preferably controlling the vibrating time of each vibrating point to be 20-30 s. The layering thickness is controlled not to be larger than 0.8 time of the length of the vibrating rod head, the vibrator is required to be inserted quickly, so that the upper concrete and the lower concrete are vibrated in the same time, the pulling-out speed is required, otherwise, the position of the vibrating rod is not easy to be filled by concrete mixture, a gap is easy to form, and the gap is slowly polymerized and filled in the vibrating process by slow pulling, so that the bubble escaping is facilitated. During vibration, the concrete is subject to floating slurry, no obvious bubbles emerge and does not sink remarkably.

When concrete is poured, a specially-assigned person is required to monitor the formwork, measures are taken in time to treat the formwork such as loosening of connecting bolts, deformation of the formwork or slurry leakage, and the top surface is leveled as required after the concrete is poured.

Concrete curing:

the precast box culvert concrete curing adopts a spraying and watering curing mode. Spray the pre-buried maintenance pipe-line system of watering maintenance when site construction in advance, maintenance pipeline branch pipe causes every prefabricated pedestal next door, ensures that the box culvert component is moist during the health preserving.

Hoisting and transporting the box culvert:

the quality of the culvert sections is checked and accepted in a prefabricated site before hoisting the culvert sections. And checking whether the inner and outer diameter sizes and the thickness are consistent with the design drawing, and whether the overall deformation condition, the appearance and the defect repair condition of the culvert section are within the specified range.

The culvert sections are hoisted (manually matched) by using a gantry crane or a truck crane, and the transport vehicles are transported to a construction site. The corner protectors are adopted to protect the corners of the box culvert before the box culvert is lifted, when the lifting starts, the box culvert is slowly stressed to be lifted to a transport vehicle at normal speed after being lifted off the ground stably, and sleepers are added to the transport vehicle for supporting. After the culvert sections fall down, the culvert sections are pulled and fixed by steel wire ropes, and the contact friction positions are protected by adding pads to prevent the culvert sections from being damaged in the transportation process.

And (3) box culvert installation:

before the box culvert is installed, the contact surface is cleaned, and meanwhile, the box culvert is subjected to transverse and longitudinal lofting on the basis of the culvert. Leveling is carried out on the surface of the culvert foundation during installation, and the box culvert is hung to the specified position of the culvert foundation by a crane. When in place, the positions of the box culvert sections are controlled by adopting culvert axis hanging lines.

When the box culvert is installed, the staggered platforms of culvert sections are accurately controlled, and particularly the staggered platforms of the top surface and the two side surfaces of the box culvert are controlled after the box culvert is in place.

Claims

1. A cross-road cementitious structure comprising: assembled box culvert, characterized by: assembled box culvert top mould port processing have protruding slot, the bottom port department processing of assembled box culvert have the protruding draw-in groove that has annular opening, protruding draw-in groove insert another assembled box culvert on in the protruding slot the four corners setting of protruding slot be used for forming the PE pipe in prestressing tendons pore, PE pipe straight line pre-buried the four corners position department of assembled box culvert top, the four corners reservation of the tube coupling of PE pipe have the pore, the pore in wear the steel strand wires, after the stretch-draw completion seam crossing and pore position fill have the grout blanket, the side of wing wall has backfill part.

2. The cross-road cementitious structure of claim 1, wherein: the assembled box culvert adopts the mould molding, the assembled box culvert include reinforced concrete culvert body, prestressing steel strand wires, wing wall, basis, movement joint, the culvert body of assembled box culvert for the whole closed reinforced concrete frame structure that the festival combination formed, wherein two the assembled box culvert dock through the socket joint mode, the assembled box culvert on seted up the grout pore.

3. The cross-road cementitious structure as defined in claim 2, wherein: when the assembly type box culvert is of a rectangular structure, the two sides of the short side of the assembly type box culvert are symmetrically provided with an upper hanging ring and a lower hanging ring, and the upper hanging ring and the lower hanging ring are of a structure perpendicular to each other by 90 degrees.