CN117306587A - Construction method of assembled upward-inclined retaining wall - Google Patents

Abstract

The invention discloses an assembled type inclined retaining wall construction method, which comprises a prefabricating method of concrete blocks, a method for calculating data and establishing a standard model of the retaining wall, a method for measuring and lofting, a method for excavating a foundation pit and carrying out foundation treatment, a method for pouring a foundation, a method for inlaying unitized blocks, a method for filling and compacting back filler of a wall and a method for closing a wall top.

Description

Construction method of assembled upward-inclined retaining wall

Technical Field

The invention relates to the technical field of highway slope protection construction, in particular to an assembly type upward inclined retaining wall construction method.

Background

Reference document "construction technology research of highway subgrade arch skeleton protection engineering" mentions a method for protecting highway subgrade side slope by adopting a cast-in-situ concrete arch skeleton, brushing the side slope after the roadbed is filled, digging a groove on the slope manually after the brushing meets the standard and design requirements, erecting a template, pouring concrete on the slope to form an arch skeleton, and protecting the road subgrade side slope, wherein the method has the following defects: manually digging a groove on the slope of the formed roadbed, so that the slope is greatly disturbed, slope collapse is easily caused, and quality and safety accidents are generated; each layer of roadbed needs to be filled in an ultra-wide way in the construction process, after the roadbed is integrally formed and stable, the roadbed is brushed again, and the earthwork of the brushed slope is reworked, so that extra construction cost is generated; the slope gradient of the side slope is controlled according to the ratio of 1:1.5, and the higher the roadbed filling height is, the larger the occupied area is; the construction organization is difficult, the working procedures of road bed slope brushing, trench excavation, concrete pouring and the like are required to be coordinated well, and the quality accidents of landslide, slumping and the like caused by the fact that the concrete pouring cannot be completed in time after the slope is molded are avoided.

Reference "exploring the construction technology of inclined retaining wall" mentions the construction process: and (3) adopting a mode of pouring concrete to form a retaining wall to carry out highway subgrade slope protection, and finishing the treatment on the retaining wall substrate. After the templates are erected, concrete is poured and the concrete is cured, an inclined retaining wall is formed to support and protect the roadbed slope, and the method has the following defects: after the concrete pouring of the retaining wall is completed, at least 7d of curing is needed, and the roadbed can be filled after the wall meets the quality requirement, so that the construction period is long, and the construction progress is not facilitated; after the upward inclined retaining wall is poured, a triangular area is formed behind the wall, so that the construction machine is not beneficial to operation, local cannot be rolled in place, and hidden quality hazards are formed behind the wall; the retaining wall needs to be poured in a layered mode, backfilled in a layered mode, multiple layers of construction joints are generated in the construction process, and the integrity of the retaining wall is poor; the retaining wall is high in one-time casting height, accumulated water cannot be discharged in time in the process of filling the roadbed behind the wall, and quality hidden danger is easily formed behind the wall.

The construction process mentioned in reference "application of spray seeding grass planting in highway side slope protection" comprises the following steps: after roadbed construction is completed and stabilized, grass seeds are directly sprayed on a slope surface, water is sprayed and permeated through the sprinkler, and maintenance is carried out on the slope surface by utilizing the root systems of plants and soil layers to carry out anchor rod protection on the roadbed slope, and the method has the defects that: after the grass seeds are sprayed and the roadbed is integrally formed, the grass seeds are performed once, the grass seeds do not play a role in protection in the construction process, and the hidden quality trouble of slope collapse still exists; spraying grass seeds cannot be performed in winter with low temperature, and the survival rate of the grass seeds is greatly influenced by seasons, so that winter construction is influenced; the grass seed root system is shorter, can only play the guard action on the side slope top layer, has the quality hidden danger that the side slope wholly collapses.

It is therefore desirable to propose a new construction method to solve the above-mentioned drawbacks.

Disclosure of Invention

First, the technical problem to be solved

In order to overcome the defects of the prior art, the construction method of the assembled upward inclined retaining wall is provided, the integral concrete retaining wall panel is divided into independent and unitized wall panel concrete blocks which are manufactured in advance, the unitized concrete blocks with unique top grooves and bottom protruding falcon structures are gradually bonded and inlaid to form the integral wall panel, and the construction of the retaining wall panel construction and roadbed filling is synchronously carried out, so that the construction period is greatly shortened, the occupied area is saved, and the cost is saved.

(II) technical scheme

The invention is realized by the following technical scheme: the invention provides an assembled upward-inclined retaining wall construction method, which comprises a prefabricating method of concrete blocks, a method for calculating data and establishing a standard model of the retaining wall, a method for measuring lofting, a method for excavating a foundation pit and carrying out foundation treatment, a method for pouring a foundation, a method for embedding unitized blocks, a method for filling and compacting wall back filler and a method for sealing a wall top.

Further, the prefabrication method of the concrete block comprises the steps of processing a concrete block mold and producing and storing the concrete block, wherein the concrete block mold is a plastic mold, the plastic mold is formed by splicing an upper part and a lower part, the splicing part is fixed by screws, the production method of the concrete block is to pour concrete into the mold and transfer the concrete into a curing area to be cured by sprinkling water, the compressive strength of the concrete is measured, and the concrete is stored after meeting the standard.

Further, the method for calculating the data and establishing the retaining wall standard model comprises the steps of initially calculating elevation and offset of the concrete blocks, drawing a prefabricated block line pattern according to the calculated data, and carrying out data adjustment on the concrete blocks to form the retaining wall standard model.

Furthermore, the measuring and lofting method comprises the step of lofting the construction side line, the foundation position and the position of the concrete block according to the data.

Further, the method for excavating the foundation pit and performing foundation treatment comprises the steps of excavating the foundation pit and performing foundation treatment construction, wherein the foundation treatment construction comprises the steps of selecting materials and performing cushion treatment.

Further, the foundation pouring method comprises foundation trench excavation, broken stone strip foundation paving and concrete strip foundation pouring.

Further, the unitized block inlaying method comprises inlaying concrete strip-shaped foundation blocks, inlaying common blocks and inlaying drainage concrete blocks.

Further, the method for filling and compacting the wall back filling material comprises the steps of filling and compacting the wall back broken stone drainage layer, and constructing the retaining wall inlay and roadbed filling running water.

Furthermore, the method for closing the wall top adopts reinforced concrete bar-shaped capping to close the wall top.

(III) beneficial effects

Compared with the prior art, the invention has the following beneficial effects:

according to the construction method of the assembled type inclined retaining wall, disclosed by the invention, an assembled type inclined retaining wall process is adopted, so that the effect of synchronous construction molding of retaining wall embedding and roadbed filling can be formed, the concrete curing period is shortened, the labor and material consumption for retaining wall construction joint treatment are reduced, large templates, attached vibrators, concrete pump trucks and the like which are required to be used in the pouring process of the large-volume retaining wall are avoided, the working efficiency is improved, and the production cost is reduced; the method provides an assembly type upward-inclined retaining wall unit block embedding forming technology, a retaining wall unit block embedding and embankment filling layering synchronous forming technology and a retaining wall unit block dynamic monitoring and adjusting technology, solves the problems of long construction period and high construction difficulty of high and steep slope protection, and has the advantages of high construction efficiency, advanced technology and mature process; in the concrete block embedding process, the actual data is compared with the standard model, so that the dynamic monitoring and adjustment of the concrete block in the construction process are realized, the deviation of the concrete block is kept at 2mm, the influence of accumulated deviation on the construction is effectively reduced, and the once acceptance rate of the concrete retaining wall is improved from 90% to 97%. By prefabricating the concrete blocks in advance, the curing time of the concrete is prolonged, the wall panel strength is far higher than that of the cast-in-situ retaining wall panel, and the quality is reliable; the assembly type upward-inclined retaining wall construction adopts left and right side-to-side width division to perform retaining wall insert molding and roadbed filling construction, so that a linear flowing water section is formed, workers and machines are prevented from being on the same working surface, and the probability of accidents is effectively reduced; the concrete block is embedded and formed before the embankment is filled and formed, a barrier is formed at the roadbed slope, and the risk that constructors drop from the high slope is effectively reduced. And the assembly type construction is adopted, a high and large template is not required to be supported, and large-volume concrete is poured, so that potential safety hazards are reduced.

Detailed Description

The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

1. Precast concrete block

(1) Concrete block mould processing

According to the size preparation 5mm thick plastic mold of concrete block, plastic mold selects high-quality producer to concentrate production, divides upper and lower two parts concatenation to form, and the concatenation department adopts the screw fixed, and bottom tenon position is as the charging hole, and the length of mould is shorter than design 5mm, can solve the length accumulated error that produces when prefabricated block concatenation construction. The periphery of the die is welded into a framework by angle steel with the thickness of 50mm and 500mm as a supporting body, the charging die is welded by steel plates with the thickness of 3mm, and the periphery is welded by adoptingThe size of the feeding hole is consistent with the size of the protruding falcon of the prefabricated building block, and each die can be recycled for about 150 times.

(2) Production and storage of concrete blocks

Placing the filled building block mould on a vibrating table, starting the vibrating table to vibrate, pouring concrete through a charging port, and keeping the vibrating table to vibrate in the pouring process for 3 times, wherein after the charging is finished, the concrete on the surface is not sunk, no bubbles are generated, when the surface presents slurry, the mould is moved to a curing area to be sprayed with water for curing, and the concrete blocks poured on the same day are marked. When the compressive strength of the concrete reaches 2.5MPa, the molding die screw can be unscrewed, the concrete block can be taken out and transported to a storage site for curing until the design strength is reached. The surface of the concrete block in the curing process can be flooded to generate small subsidence, and the material is manually re-fed to finish and light before the initial setting of the concrete. And after the concrete curing is finished, detecting the strength by adopting a rebound instrument, and when the strength reaches the design strength of 30MPa, the concrete curing machine can be used for retaining wall construction.

2. Data preparation

(1) Data computation

1) Preliminary calculation of elevation and offset of concrete block

And preliminarily calculating the elevation and offset of each layer of prefabricated building block according to the design slope according to the design road surface edge position and the design slope according to the design drawing road surface width, slope gradient and the dimensions of the prefabricated building blocks, and drawing a CAD prefabricated building block line type diagram according to the calculated data.

2) Concrete block data adjustment

Four factors including a concrete block layered staggered joint embedding process, positions of water discharge holes, positions of expansion joints and sedimentation joints and a retaining wall layered embedded starting point are considered, influence is exerted on a concrete building position, the factors are analyzed gradually, the positions of the concrete blocks are adjusted, and a final layout of the concrete blocks is formed.

a. Layered staggered joint inlaying process for concrete block

In order to avoid the retaining wall to vertically form the expansion joint and subside the seam except the seam, the uneven subsidence of seam both sides appears, leads to the hidden danger that the wall top produced reflection crack finally. When each layer of concrete block is inlaid, the middle part of the upper layer of concrete block is adjusted to be pressed on the seam of the lower bearing layer of concrete block, and as the lengths of the concrete blocks are all integral multiples of 25cm, the concrete blocks of each layer can be uniformly distributed, so that the through seam is avoided.

b. The position of the water discharge hole

In order to prevent the water accumulation on the back of the retaining wall from damaging the retaining wall and causing wall dislocation and collapse, concrete blocks with phi 75PVC drainage pipes are embedded in the wall according to 2 x 2m plum blossom intervals, so that smooth drainage of the back of the wall is ensured.

c. The positions of the expansion joint and the sedimentation joint

In order to ensure that the concrete retaining wall is free to crack due to uneven settlement in the vertical direction, the concrete retaining wall can be freely stretched and contracted under the influence of temperature in the transverse direction, the wall structure is not damaged, expansion joints with the through length are arranged every 10m on the wall, the joint width is 2cm, 19I-shaped structural building blocks with the length of 50cm and 2 II-shaped adjusting building blocks with the length of 25cm can be arranged between the two expansion joints, and the concrete building block layout is adjusted again.

d. Start point for layering inlay of retaining wall

Because different types of curve roads exist on the standard ramp, the starting points of the layered inlay of the retaining wall are required to be arranged at the slope lifting position according to the road surface elevation of each gradient road, and the concrete retaining wall height and the road longitudinal gradient road surface are kept to be changed synchronously.

And (3) comprehensively considering the four factors, adjusting the positions of the concrete blocks, finally establishing a retaining wall plan at CAD, and establishing a retaining wall three-dimensional map at REVIT to form a standard model for site construction control.

3. Measurement lofting

The constructor uses GPS to loft construction sidelines, basic position, concrete block position etc. according to the data sheet, loft every 10m in straight line paragraph, loft every 2m in curve position, constructor follow the constructor to spill grey sign, after the loft is accomplished, use the lime line to connect all positions, clear position, be convenient for construction. When the concrete block is lofted, constructors drive steel drills into corresponding points of the roadbed, and the steel drills are tied to the lines to ensure that the lines are stable and do not fall down and serve as inner side control side lines when the concrete block is inlaid.

4. Pit excavation

And excavating to a stable bearing stratum according to project address investigation report content.

5. Foundation treatment

(1) Foundation treatment form and material selection

The method is characterized in that crushed stone filler with the grain diameter not larger than 30cm is selected as a crushed stone cushion layer and used for removing underground water, 6% of a lime-soil cushion layer is filled between crushed stone and fine-grained soil and used as a water-absorbing cushion layer between the crushed stone cushion layer and the fine-grained soil to intercept the underground water from rising to a embankment and retaining wall foundation, and meanwhile, the crushed stone filler is used as a transition layer between the crushed stone and the fine-grained soil to keep good combination of different filler layers.

(2) Foundation treatment construction

Construction of stone cushion

The broken stone cushion layer is transported to the foundation pit by using a transport vehicle, is discharged from far to near, is leveled by the cooperation of an excavator, keeps the filling compaction thickness of each layer to be 50cm, is close to the side slope of the foundation pit, is slowly pushed by using bucket teeth of the excavator, is evenly paved, and avoids disturbance to the side slope to collapse. After the broken stone is paved and leveled, the broken stone cushion layer is subjected to static pressure by using an excavator and a road roller, the surface is kept flat, no rolling track exists, and no slope shortage phenomenon exists in the construction of the lime-soil cushion layer

And after the loading of the transport vehicle, the material is discharged from the foundation pit from far to near, a bulldozer spreads and levels, a road roller rolls, the surface is kept smooth, no rolling track exists, layered construction is carried out, and finally the construction of a gray soil cushion layer is completed.

6. Foundation pouring

(1) Foundation trench excavation

The foundation trench is excavated downwards to the designed elevation by using the excavator according to the paying-off position of the measuring personnel, the measuring personnel can detect the excavation width and the elevation at any time by holding a GPS in the excavation process, the overexcavation and underexcavation are prevented, the foundation is leveled by using the excavator bucket teeth after the excavation is completed, and the leveling is kept.

(2) Stone strip foundation laying

And loading by using a loader, paving and leveling broken stone by using an excavator in combination with the loader, wherein the broken stone strip foundation is 50cm, and paving the broken stone strip foundation in two layers of 25cm in sequence, and manually holding the GPS to control the elevation of the substrate so as to prevent overexcavation and underexcavation.

(3) Concrete strip foundation pouring

After the broken stone strip foundation is paved, constructors prop up and establish the concrete template according to the paying-off position of measuring staff, brush isolating agent at the template inboard, be convenient for follow-up concrete drawing of patterns, throw in the reinforcing bar at every 1m at template inside and outside both sides and fix, fix at the reinforcing bar head ligature iron wire that stretches out, the horizontal impact force that produces when preventing to pour the concrete and the horizontal impact force that produces when vibrating the stick and vibrating, make the template slope. And marking the two side end templates, marking the positions of the concrete grooves, installing the groove templates by constructors, fixing the groove templates by iron, and keeping the heights of the tops of the groove templates consistent with the heights of the peripheral templates.

After the template is supported, a measurer rechecks the position of the inner edge line of the template, aligns with the design position, and carries out the next procedure after the report and supervision engineer passes the acceptance.

During concrete pouring, the distance between the discharge hole and the substrate is kept to be not more than 2m, segregation is prevented from occurring, in the concrete pouring process, the handheld vibrating rod vibrates, the groove template is strictly forbidden to touch in the vibrating process, inclination is avoided, the position of the groove is prevented from being deviated, and the concrete retaining wall cannot be inlaid. When the concrete is not sinking, no bubble appears, and the surface presents the magma, stop vibrating, begin to carry out the flattening and handle, use the scraping bar to scrape along template top back and forth and move, guarantee concrete top surface and template top surface parallel and level, when the hole appears on the concrete surface, the manual work uses the spatula to smear cement mortar and grinds the level, carries out the health preserving after accomplishing. And when the strength of the concrete reaches 2.5MPa, removing the template, and when the strength of the concrete reaches the design strength, performing the construction of the next working procedure.

7. Unitized block inlay

(1) Concrete strip foundation block inlay

The measuring staff is lofted every 10m in the straight line paragraph, lofted every 2m in the curve paragraph, the constructor uses the marker pen to mark the point position, uses the ink fountain elastic line to connect all the point positions, and is used as the control sideline of retaining wall concrete block. After paying off, constructors smear M10 cement binding mortar in the grooves, the smearing area is not smaller than 1/3 of the area of the grooves, the constructors move the concrete blocks to the grooves every 2 persons, the age difference among the concrete blocks of the same layer is kept within 10d, and the maximum age difference is not more than 30d, so that the quality hidden trouble caused by uneven strength among different blocks is prevented. The concrete block is connected with the concrete strip-shaped foundation through the bonding mortar, the bottom of the transverse concrete block is in close contact with the top surface of the concrete strip-shaped foundation, the concrete block is kept accurate in elevation, the edge of the vertical concrete block is kept vertically aligned with the ink duct line mark, and the concrete block offset distance is kept accurate.

(2) Common building block inlay

Because the retaining wall concrete block keeps higher than the retaining wall back filler 2 layers by 50cm consistently, guarantee constructor safety simultaneously, constructor is inboard at the building block, be close to filler one side, beat and establish the reinforcing bar as control point position, regard as concrete block control sideline at the reinforcing bar ligature cotton rope, constructor paints cement mortar in the concrete top recess, move the building block and inlay to the recess, keep concrete building block bottom and last layer building block top close joint, the side is vertically aligned with the cotton rope in the concrete building block, guarantee concrete building block position and design position accuracy.

(3) Water-draining concrete block inlay

According to the calculated data, concrete blocks provided with PVC drain pipes are embedded in corresponding positions to form drain holes of the retaining wall, the construction process is the same as that of common blocks, the PVC drain pipes are close to one side of the back of the wall, the pipeline ports are fully wrapped by geotechnical cloth, iron wires are used for binding and fixing, the PVC drain pipes are used as a reverse filtering layer, filler on the back of the wall is prevented from entering the drain holes, the drainage function is affected, the filler loss is prevented, holes appear behind the wall, and potential quality hazards are formed.

8. Wall back filling and compacting

(1) Filling and compacting of wall back broken stone drainage layer

The wall back is provided with a 300mm thick broken stone drainage layer, the drainage layer is made of graded broken stone materials with good water permeability, the graded broken stone materials and the wall back roadbed are filled synchronously according to the layer thickness of 15cm, firstly, a loader shovel is used, the cement is slowly poured on the inner side of a concrete block, a small rammer is used for rough leveling, then the wall back 6% lime soil roadbed is filled, a transport vehicle is used for transporting materials, a bulldozer is used for leveling, the grader is used for leveling and compacting by a road roller, and after the wall back 6% lime soil roadbed is compacted, the manual rammer and the small rammer are used for simultaneously compacting the 6% lime soil and the broken stone drainage layer within the range of 1m from the wall back, so that disturbance to the wall back is avoided.

(2) Retaining wall inlaid and roadbed filling flow construction

When the standard ramp is constructed, the whole area is divided into a left area and a right area, the wall back gray soil roadbed, the broken stone drainage layer and the concrete block embedding process are coordinated and arranged, a running water section construction method is formed, when the embedded construction team is on the left area, the embedded construction team is constructed on the right area, the embedded construction team is not interfered with each other, the influence caused by cross construction is avoided, the safety of operators of the embedded construction team is ensured, and the probability of safety accidents is reduced.

9. Wall top closure

When the retaining wall concrete block is inlaid to the design elevation, the reinforced concrete bar-shaped coping is adopted to seal the wall top, all the blocks at the top are rigidly connected together, the overall stability of the concrete retaining wall is enhanced, the coping and the line type synchronous change are consistent with the line forming surface, the starting points of the uneven concrete retaining wall inlaying layers are adjusted, and the overall attractiveness is ensured.

The above examples are merely illustrative of the preferred embodiments of the present invention and are not intended to limit the spirit and scope of the present invention. Various modifications and improvements of the technical scheme of the present invention will fall within the protection scope of the present invention without departing from the design concept of the present invention, and the technical content of the present invention is fully described in the claims.

Claims (9)

1. A construction method of an assembled upward-inclined retaining wall is characterized by comprising the following steps: the method comprises a prefabrication method of concrete blocks, a method for calculating data and establishing a retaining wall standard model, a method for measuring lofting, a method for excavating a foundation pit and carrying out foundation treatment, a method for pouring a foundation, a method for embedding unitized blocks, a method for filling and compacting a wall back filler and a method for sealing a wall top.

2. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the prefabrication method of the concrete block comprises the steps of processing a concrete block mold and producing and storing the concrete block, wherein the concrete block mold is a plastic mold, the plastic mold is formed by splicing an upper part and a lower part, the splicing part is fixed by screws, the production method of the concrete block is to pour concrete into the mold and transfer the concrete into a curing area to be cured by sprinkling water, the compressive strength of the concrete is measured, and the concrete is stored after meeting the standard.

3. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the method for calculating the data and establishing the retaining wall standard model comprises the steps of initially calculating elevation and offset of the concrete blocks, drawing a prefabricated block line type diagram according to the calculated data, and carrying out data adjustment on the concrete blocks to form the retaining wall standard model.

4. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the method for measuring and lofting comprises the step of lofting the construction side line, the foundation position and the position of the concrete block according to the data.

5. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the method for excavating the foundation pit and performing foundation treatment comprises the steps of excavating the foundation pit and performing foundation treatment construction, wherein the foundation treatment construction comprises the steps of selecting materials and performing cushion treatment.

6. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the foundation pouring method comprises foundation trench excavation, broken stone strip foundation paving and concrete strip foundation pouring.

7. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the unitized block inlaying method comprises inlaying concrete strip-shaped foundation blocks, inlaying common blocks and inlaying drainage concrete blocks.

8. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the method for filling and compacting the wall back filling material comprises the steps of filling and compacting the wall back broken stone drainage layer, and constructing the retaining wall inlay and roadbed filling running water.

9. The construction method of the assembled upward-inclined retaining wall according to claim 1, wherein the construction method comprises the following steps: the method for closing the wall top adopts a reinforced concrete strip-shaped capping to close the wall top.