Assembled concrete box retaining wall and construction method thereof

Abstract

The invention discloses an assembled concrete box retaining wall and a construction method thereof, comprising a cast-in-place foundation and a wall body arranged above the cast-in-place foundation, wherein the upper surface of the cast-in-place foundation is provided with an inwardly concave string-shaped groove, and the wall body is a multi-layer structure, wherein each layer of the wall body comprises a plurality of interconnected prefabricated concrete box monomers, and the ends of two adjacent prefabricated concrete box monomers in the single-layer wall body are connected by side wall blocks. Compared with a traditional gravity retaining wall, the invention adopts a hollow concrete box to fill abandoned earth and stone materials, which can reduce about 40% of the masonry or concrete volume, reasonably utilizes the abandoned earth and stone materials of the project, reduces the abandoned materials of the project, and can reduce the project cost by more than 15%. The assembled retaining wall provided by the invention has a minimum assembly unit which is a prefabricated concrete box monomer, and all the prefabricated concrete box monomers have the same size, which is convenient for standardized production, and the assembly construction is convenient, and the on-site construction period can be reduced by more than 30%.

Description

Technical Field

[0001] The present invention belongs to the field of geotechnical engineering technology, and specifically relates to an assembled concrete box retaining wall and a construction method thereof, which is suitable for rapid slope support and protection of new construction projects such as highways, railways, and municipal projects, and can also be used for rapid reinforcement and control of slope instability diseases during operation. Background Art

[0002] Retaining wall is one of the most commonly used retaining structures in geotechnical engineering. The main structural forms of retaining wall include gravity type, buttress type, reinforced type, anchor type, pile plate type, etc. In the construction of highway, railway, municipal, water conservancy and other projects, gravity retaining wall is the most widely used. Traditional gravity retaining wall is generally built by stone stacking and concrete pouring on site, which requires a large amount of masonry, many consumables, and high cost. At the same time, the on-site construction is not highly mechanized, the efficiency is low, and the construction period is long.

[0003] In order to reduce construction costs and shorten construction periods, gravity-type prefabricated retaining walls have appeared in the prior art in recent years. For example, invention patents ZL201720712366.0 and ZL201721376162.0 respectively disclose a prefabricated assembled retaining wall, in which the overall retaining wall is composed of a number of box units assembled on site through plates, beams and connectors, and the box units can be filled with soil and slag, which can effectively reduce the masonry consumption of traditional assembled retaining walls and reduce the construction cost. However, the on-site assembly units of this type of structure are too small, the components are numerous, the assembly process requirements are high, and the overall self-stability of the retaining wall is difficult to ensure. The invention patents with application numbers 201610479129.4, 201810570406.1 and 201810167122.8 are respectively disclosing a prefabricated assembled concrete box-type gravity retaining wall. These three new retaining walls are all composed of prefabricated concrete square box units (the detailed structures of the three box units are different). During on-site construction, the prefabricated square box units are directly stacked in layers, and soil and stone materials are filled into the empty boxes, which is convenient for construction. However, the cross-sections of these types of retaining walls have the same width from top to bottom and are all composed of a row of boxes. According to the distribution characteristics of the soil pressure of the retaining wall, which is small at the top and large at the bottom, these retaining walls should not be too high. At the same time, the overall stability of the retaining wall has extremely high requirements on the assembly process. When the retaining wall is high, the risk of overall overturning is relatively high. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, one of the purposes of the present invention is to provide an assembled concrete box retaining wall, which has safe and reliable structural performance, is economical and practical, energy-saving and environmentally friendly, and has wide applicability. It can be used for rapid support and protection of slopes in newly built roads, railways, municipal engineering, etc., and can also be used for rapid reinforcement and control of slope instability diseases during operation.

[0005] The second purpose of the present invention is to provide a construction method for an assembled concrete box retaining wall. The main advantage of the present invention is to implement standardized and industrialized construction of the retaining wall, while maximizing the safety performance and energy-saving and environmental protection functions of the retaining wall. It not only has a simple structure and rapid construction, but also has convenient structural repair, and the project is safe, economical and environmentally friendly.

[0006] To achieve the above purpose, the technical solution provided by the present invention is as follows:

[0007] An assembled concrete box retaining wall comprises a cast-in-place foundation and a wall body arranged above the cast-in-place foundation, wherein the upper surface of the cast-in-place foundation is provided with an inwardly concave string-shaped groove, the wall body is a multi-layer structure, each layer of the wall body comprises a plurality of mutually connected precast concrete box monomers, the ends of two adjacent precast concrete box monomers in the single-layer wall body are connected by side wall clamping blocks, the bottom surface of the precast concrete box monomer protrudes outward with a string-shaped convex ridge corresponding to the string-shaped groove, the top surface of the precast concrete box monomer is provided with a strip-shaped groove matched with the string-shaped convex ridge, and the precast concrete box monomer arranged on the bottom wall is correspondingly installed on the string-shaped groove on the cast-in-place foundation through the string-shaped convex ridge;

[0008] Every two layers of the wall above the cast-in-place foundation form a group, and the width of the multiple groups of walls decreases from bottom to top, and the decreasing width is equal to the width of the precast concrete box body. An interlayer clamp block prefabricated by a steel mesh and concrete is provided between two adjacent groups of walls, and the top surface of the interlayer clamp block is provided with a string-shaped groove matched with the string-shaped convex ridge, and the bottom surface of the interlayer clamp block is concave with an I-shaped groove, and the interlayer clamp block is installed above the two precast concrete box bodies arranged side by side below;

[0009] The prefabricated concrete box units in two adjacent layers of walls are staggered.

[0010] Preferably, the precast concrete box unit is a hollow structure with an open top precast by steel mesh concrete, and its outer contour length, width and height are 200cm, 100cm and 100cm respectively. The wall thickness of the precast concrete box unit is 8-15cm. Rectangular windows for installing side wall blocks are provided at the two side walls of the precast concrete box unit. The side wall blocks are precast by steel mesh and concrete as a whole. The rectangular window is 40cm long and 20-30cm wide. The strip groove is provided at the upper edge of the side walls at both ends, with a length of 50cm and a width of 10cm. The thickness of the string-shaped convex ridge is 8-15cm.

[0011] Preferably, drainage holes with a diameter of 10 cm are provided on the front and rear sides of the precast concrete box unit, and each precast concrete box unit has four drainage holes, which are distributed in pairs on the front and rear side walls of the precast concrete box unit.

[0012] Preferably, the cavity of the prefabricated concrete box unit is filled with waste soil.

[0013] Preferably, the exposed surface of the waste soil is planted with grass and shrubs.

[0014] The waste soil materials mentioned above are the waste slag discarded from engineering excavation or the soil and stone materials mined from the adjacent borrow pit, etc., which can be high-quality fillers such as crushed stone soil and sand and gravel, or poor fillers such as expansive soil, high liquid limit soil, soft rock, weathered rock, residual soil, etc. The waste soil materials are used to fill the concrete box cavity of the retaining wall to increase the weight of the retaining wall.

[0015] The grass and shrub vegetation is grass seeds, shrub seeds, or climbing vine seeds adapted to local growth habits, which are sown in the soil layer of the retaining wall platform to green the slope surface.

[0016] Preferably, the cross-section of the side wall block is a "door"-shaped structure, each wall thickness of the "door"-shaped structure is 10-15 cm, and the outer contour dimensions of the side wall block are 40 cm in length, 20-30 cm in width, and 20-30 cm in height, respectively.

[0017] Preferably, the cast-in-place foundation is a thin concrete slab cast on the foundation, with a thickness of 20-30 cm and a width of 3-5 m. In the length direction, an expansion joint is provided every 10 m.

[0018] The present invention also provides a construction method for the above-mentioned assembled concrete box retaining wall, comprising the following steps:

[0019] Step 1: Process a certain number of prefabricated concrete box units, interlayer blocks, and side wall blocks according to standard sizes at the prefabrication site, maintain them to the designed strength, and transport them to the construction site for assembly;

[0020] Step 2: Level the site, compact the foundation, and construct a certain length of cast-in-place foundation on the foundation to be built according to the designed length of the retaining wall. According to the designed cross-sectional size of the retaining wall, use the template to synchronously make a series of groove arrays on the cast-in-place foundation when casting the foundation;

[0021] Step 3: Use a truck crane to hoist the precast concrete box monomers, and place them one by one in the cast-in-place foundation string groove array. The two adjacent precast concrete box monomers on the left and right are connected by side wall blocks, and then waste soil is loaded into the cavities of the precast concrete box monomers one by one to form the first layer of retaining wall;

[0022] Step 4: Install prefabricated concrete box units one by one on the top surface of the first retaining wall in a staggered manner according to step 3, so as to form a second retaining wall with equal cross-section;

[0023] Step 5: on the top surface of the second layer retaining wall, place the interlayer clamping blocks one by one through the I-shaped grooves on the top of the side walls of the two adjacent precast concrete box monomers, forming a clamping block array with one row less than the second layer, and then install the precast concrete box monomers on the interlayer clamping blocks according to the front and back staggered seams to form the third layer retaining wall;

[0024] Step 6: Repeat the installation of prefabricated concrete box units by changing the cross-sectional width every two layers until the designed height of the retaining wall is reached, thus forming a long strip of 'Tower of Hanoi'-style concrete box retaining wall.

[0025] Step 7: Backfill the gravel soil filling material on the back of the retaining wall and compact it layer by layer with a small machine;

[0026] Step 8. Plant grass, shrubs or climbing plants in the platform on one side of the retaining wall and in the soil layer of the top concrete box to green the wall.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) Economical and practical: Compared with traditional gravity retaining walls, the present invention uses hollow concrete boxes to fill waste earth and stone materials, which can reduce about 40% of the masonry or concrete volume, rationally utilize the waste earth and stone materials of the project, reduce the waste volume of the project, and reduce the project cost by more than 15%.

[0029] (2) Quick construction: The smallest assembly unit of the prefabricated retaining wall provided by the present invention is a prefabricated concrete box unit, and all prefabricated concrete box units have the same size, which is convenient for standardized production and quick assembly and construction, and the on-site construction period can be reduced by more than 30%.

[0030] (3) Safety and durability: Compared with prefabricated assembled concrete box-type gravity retaining walls, the assembled retaining wall of the present invention innovatively adopts a "Tower of Hanoi" cross-section. Compared with the existing assembled retaining walls with equal cross-section structures, the retaining wall provided by the present invention has better self-stability. At the same time, the present invention adopts left-right clamping and upper-lower staggered assembly construction. The retaining wall has good integrity and higher safety. It has higher applicable slope support strength. The maximum retaining wall height of the present invention is more than 20% higher than that of the existing assembled retaining wall.

[0031] (4) Environmentally friendly: Compared with the existing prefabricated retaining walls, the present invention utilizes the retaining wall platform and the top open concrete box soil layer to plant grass and shrubs and green the retaining wall slope; at the same time, the retaining wall structure rationally utilizes the waste earth and stone of the project, reduces the amount of engineering masonry, saves resources, and is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 This is an overall three-dimensional structural diagram of an assembled concrete box retaining wall of the present invention;

[0034] Figure 2 It is a cross-sectional view of an assembled concrete box retaining wall of the present invention;

[0035] Figure 3 This is a front view of an assembled concrete box retaining wall of the present invention;

[0036] Figure 4 It is a three-dimensional structural diagram of the prefabricated concrete box monomer of the present invention;

[0037] Figure 5 It is a side view of the prefabricated concrete box unit of the present invention;

[0038] Figure 6 It is a front view of the prefabricated concrete box unit of the present invention;

[0039] Figure 7 It is a bottom view of the prefabricated concrete box unit of the present invention;

[0040] Figure 8 It is a three-dimensional structural diagram of the interlayer sandwich block of the present invention;

[0041] Fig. 9 It is a top view of the interlayer sandwich block of the present invention;

[0042] Fig.10 It is a bottom view of the interlayer sandwich block of the present invention;

[0043] Fig.11 It is a three-dimensional structural diagram of the side wall block of the present invention;

[0044] Fig.12 It is a three-dimensional structural diagram of the cast-in-place foundation of the present invention.

[0045] The following are the descriptions of the reference numerals:

[0046] 1. Prefabricated concrete box unit; 2. Interlayer blocks; 3. Side wall blocks; 4. Cast-in-place foundation; 5. Waste soil; 6. Grass and shrub vegetation; 7. Drainage outlet; 8. Rectangular window; 9. Strip groove; 10. String-shaped ridge; 11. String-shaped groove; 12. I-shaped groove; 13. Expansion joint; 14. String-shaped groove. DETAILED DESCRIPTION

[0047] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0048] As shown in the figure, the present invention provides an assembled concrete box retaining wall, including a cast-in-place foundation 4 and a wall body arranged above the cast-in-place foundation 4, the upper surface of the cast-in-place foundation 4 is provided with an inwardly concave string-shaped groove 14, and the string-shaped groove 14 is arranged in three rows; the wall body is a multi-layer structure, and each layer of the wall includes a plurality of interconnected prefabricated concrete box monomers 1, specifically, the ends of two adjacent prefabricated concrete box monomers 1 in a single-layer wall are connected by side wall blocks 3, and the side wall blocks 3 are installed in a rectangular window 8 opened on the side of the prefabricated concrete box monomer 1, and the bottom surface of the prefabricated concrete box monomer 1 protrudes outward with a groove corresponding to the string-shaped groove 14 The bottom wall is also provided with three rows of precast concrete box monomers 1. When the bottom wall is installed, the string-shaped ridges 10 below the precast concrete box monomers 1 are correspondingly installed in the string-shaped grooves 14 on the upper surface of the cast-in-place foundation 4, which can limit the horizontal movement of the precast concrete box monomers 1. Under the action of gravity, the precast concrete box monomers 1 are stationary on the cast-in-place foundation 4 and remain stable. The top surface of the precast concrete box monomers 1 is provided with strip grooves 9 that match the string-shaped ridges 10. The precast concrete box monomers 1 arranged on the bottom wall are correspondingly installed on the string-shaped grooves 14 on the cast-in-place foundation 4 through the string-shaped ridges 10.

[0049] Every two layers of the wall above the cast-in-place foundation 4 form a group, and the width of the multiple groups of walls decreases from bottom to top, and the decreasing width is equal to the width of the precast concrete box monomer 1. This arrangement is to form a long strip of "Tower of Hanoi" type cross-section concrete box retaining wall structure, which can improve the stability of the retaining wall. An interlayer clamp 2 is provided between two adjacent groups of walls. The interlayer clamp 2 is a rectangular concrete block. The top surface of the interlayer clamp 2 is provided with a string-shaped groove 11 that matches the string-shaped convex ridge 10, and the bottom surface of the interlayer clamp 2 is concave with an I-shaped groove 12. The interlayer clamp 2 is installed above the two precast concrete box monomers 1 arranged side by side below, and the interlayer clamp 2 is used to play a transition connection role in the transition area where the width of the retaining wall narrows;

[0050] The prefabricated concrete box units 1 in two adjacent layers of walls are staggered, so that each prefabricated concrete box unit 1 can be evenly stressed and stable.

[0051] As an optional embodiment, the precast concrete box monomer 1 is a hollow structure with an open top, and its outer contour length, width and height are 200 cm, 100 cm and 100 cm respectively. The wall thickness of the precast concrete box monomer 1 is 15 cm. The two side walls of the precast concrete box monomer 1 are provided with rectangular windows 8 for installing side wall blocks 3. The rectangular windows 8 are 40 cm long and 20 cm wide. The strip grooves 9 are provided at the upper edges of the two end side walls, with a length of 50 cm and a width of 15 cm. The thickness of the string-shaped ridges 10 is 15 cm.

[0052] The front and rear side surfaces of the precast concrete box unit 1 are provided with drainage holes 7 with a diameter of 10 cm. There are four drainage holes 7 on each of the precast concrete box units 1. The four drainage holes 7 are distributed in pairs on the front and rear side walls of the precast concrete box unit 1. The drainage holes 7 are used for rainwater to penetrate the waste soil 5 on rainy days and finally be discharged from the drainage holes 7 to avoid the collapse of the retaining wall.

[0053] The cavity of the prefabricated concrete box monomer 1 is filled with waste soil 5, wherein the waste soil 5 is waste slag discarded from engineering excavation or soil and stone materials mined from adjacent borrow pits, etc., and can be high-quality fillers such as crushed stone, sand and gravel, or poor fillers such as expansive soil, high liquid limit soil, soft rock, weathered rock, residual soil, etc. The waste soil 5 is used to fill the concrete box cavity of the retaining wall to increase the weight of the retaining wall.

[0054] The waste soil material 5 is planted with grass and shrub vegetation 6, which is grass seeds, shrub seeds, or climbing vine seeds that are adapted to the local growth habits and are sown in the soil layer of the retaining wall platform to green the slope.

[0055] The side wall block 3 is a steel mesh concrete soil strip block with a "door" shaped cross section. The thickness of each wall of the "door" shaped structure is 15 cm. The outer contour dimensions of the side wall block 3 are 40 cm in length, 20 cm in width, and 20 cm in height, respectively. The two adjacent prefabricated concrete box units 1 are connected by the side wall block 3, thereby improving the stability of the retaining wall.

[0056] The cast-in-place foundation 4 is a concrete slab cast on the foundation, with a thickness of 30 cm and a width of 5 m. The length is determined according to the design length of the retaining wall. In the length direction, an expansion joint 13 is provided every 10 m to prevent the concrete slab from cracking due to thermal expansion and contraction.

[0057] This embodiment also provides a construction method for the above-mentioned assembled concrete box retaining wall, comprising the following steps:

[0058] Step 1: Process a certain number of prefabricated concrete box monomers 1, interlayer blocks 2, and side wall blocks 3 according to standard sizes in the prefabrication yard, maintain them to the designed strength, and transport them to the construction site for assembly;

[0059] Step 2: Level the site, compact the foundation, and construct a cast-in-place foundation 4 of a certain length on the foundation to be built according to the designed length of the retaining wall. According to the designed cross-sectional size of the retaining wall, use a template to synchronously make a series of grooves 14 arrays on the cast-in-place foundation 4 when casting the foundation 4;

[0060] Step 3: Use a truck crane to hoist the precast concrete box monomers 1, and place them one by one in the array of the string-shaped grooves 14 of the cast-in-place foundation 4. The two adjacent precast concrete box monomers 1 on the left and right are connected by the side wall blocks 3, and then the waste soil 5 is loaded into the cavity of the precast concrete box monomers 1 one by one to form the first layer of retaining wall;

[0061] Step 4: Install the prefabricated concrete box units 1 one by one on the top surface of the first retaining wall in a staggered manner according to step 3, so as to form a second retaining wall with a uniform cross-section;

[0062] Step 5: on the top surface of the second layer retaining wall, place the interlayer clamping blocks 2 one by one on the top of the side walls of the two adjacent precast concrete box monomers 1 through the I-shaped grooves to form a clamping block array with one row less than the second layer, and then install the precast concrete box monomers 1 on the interlayer clamping blocks 2 in a staggered manner to form the third layer retaining wall;

[0063] Step 6: Repeat the installation of the prefabricated concrete box unit 1 by changing the cross-sectional width every two layers until the designed height of the retaining wall is reached, thereby forming a long strip of 'Tower of Hanoi' type cross-sectional concrete box retaining wall.

[0064] Step 7: Backfill the gravel soil filling material on the back of the retaining wall and compact it layer by layer with a small machine;

[0065] Step 8. Plant grass, shrubs or climbing plants in the platform on one side of the retaining wall and in the soil layer of the top concrete box to green the wall.

[0066] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An assembled concrete box retaining wall, characterized in that: The invention comprises a cast-in-place foundation (4) and a wall arranged above the cast-in-place foundation (4), wherein the upper surface of the cast-in-place foundation (4) is provided with an inwardly concave string-shaped groove (14), and the wall is a multi-layer structure, wherein each layer of the wall comprises a plurality of interconnected precast concrete box units (1), wherein the precast concrete box units (1) are an open-top hollow box structure precast from reinforced mesh concrete, and the ends of two adjacent precast concrete box units (1) in the single-layer wall are connected via a side wall block (3), and the bottom surface of the precast concrete box units (1) is provided with a string-shaped convex ridge (10) protruding outwardly and corresponding to the string-shaped groove (14), and the top surface of the precast concrete box units (1) is provided with a strip-shaped groove (9) matching the string-shaped convex ridge (10), and the precast concrete box units (1) arranged on the bottom wall are correspondingly mounted on the string-shaped groove (14) on the cast-in-place foundation (4) via the string-shaped convex ridge (10); Wherein, every two layers of the wall above the cast-in-place foundation (4) form a group, and the widths of the multiple groups of walls decrease from bottom to top, and the decreasing width is equal to the width of the precast concrete box monomer (1). An interlayer sandwich block (2) prefabricated from a steel mesh and concrete is provided between two adjacent groups of walls, and the top surface of the interlayer sandwich block (2) is provided with a string-shaped groove (11) matching with the string-shaped convex ridge (10), and the bottom surface of the interlayer sandwich block (2) is concave with an I-shaped groove (12). The interlayer sandwich block (2) is installed above the two precast concrete box monomers (1) arranged side by side below; the precast concrete box monomers (1) in the two adjacent layers of the wall are staggered. The cross section of the side wall block (3) is a "door"-shaped structure, the thickness of each wall of the "door"-shaped structure is 10-15 cm, and the outer dimensions of the side wall block (3) are 40 cm in length, 20-30 cm in width, and 20-30 cm in height, respectively; The cast-in-place foundation (4) is a thin concrete slab cast on the foundation, with a thickness of 20-30 cm and a width of 3-5 m. In the length direction, an expansion joint (13) is provided every 10 m.

2. According to claim 1, the assembled concrete box retaining wall is characterized in that: The outer contour length, width and height of the precast concrete box monomer (1) are 200 cm, 100 cm and 100 cm respectively. The wall thickness of the precast concrete box monomer (1) is 8-15 cm. The two side walls of the precast concrete box monomer (1) are provided with rectangular windows (8) for installing side wall blocks (3). The side wall blocks are integrally prefabricated by steel mesh and concrete. The rectangular windows (8) are 40 cm long and 20-30 cm wide. The strip grooves (9) are provided at the upper edges of the side walls at the two ends, with a length of 50 cm and a width of 10 cm. The thickness of the string-shaped convex ridges (10) is 8-15 cm.

3. According to claim 2, the assembled concrete box retaining wall is characterized in that: Drainage openings (7) with a diameter of 10 cm are provided at the front and rear side positions of the precast concrete box monomer (1), and there are four drainage openings (7) on each precast concrete box monomer (1). The four drainage openings (7) are distributed in pairs on the front side wall and the rear side wall of the precast concrete box monomer (1).

4. The assembled concrete box retaining wall according to claim 2 is characterized in that: The cavity of the prefabricated concrete box unit (1) is filled with waste soil (5).

5. The assembled concrete box retaining wall according to claim 4 is characterized in that: The exposed surface of the waste soil (5) is planted with grass and shrub vegetation (6).

6. A construction method for an assembled concrete box retaining wall according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: Process a certain number of prefabricated concrete box units (1), interlayer blocks (2), and side wall blocks (3) according to standard sizes at the prefabrication site, maintain them to the designed strength, and transport them to the construction site for assembly; Step 2: Level the site, compact the foundation, and construct a cast-in-place foundation (4) of a certain length on the foundation to be built according to the designed length of the retaining wall. According to the designed cross-sectional dimensions of the retaining wall, use a template to synchronously make a series of grooves (14) arrays on the cast-in-place foundation (4) when the cast-in-place foundation (4) is constructed; Step 3: Use a truck crane to hoist the precast concrete box units (1), and place them one by one in the array of the serial grooves (14) of the cast-in-place foundation (4). The two adjacent precast concrete box units (1) on the left and right are connected by the side wall blocks (3), and then waste soil (5) is placed one by one in the cavities of the precast concrete box units (1) to form the first layer of retaining wall; Step 4: Install the prefabricated concrete box units (1) one by one on the top surface of the first layer retaining wall in a staggered manner according to step 3, so as to form a second layer retaining wall with a uniform cross-section; Step 5: on the top surface of the second layer retaining wall, the interlayer clamping blocks (2) are placed one by one on the top of the side walls of the two adjacent precast concrete box monomers (1) through the I-shaped grooves to form a clamping block array with one row less than the second layer, and then the precast concrete box monomers (1) are installed on the interlayer clamping blocks (2) in a staggered manner to form the third layer retaining wall; Step 6: Repeat the installation of the prefabricated concrete box unit (1) by changing the cross-sectional width every two layers until the designed height of the retaining wall is reached, thereby forming a long strip of 'Tower of Hanoi' type cross-sectional concrete box retaining wall; Step 7: Backfill the gravel soil filling material on the back of the retaining wall and compact it layer by layer with a small machine; Step 8. Plant grass, shrubs or climbing plants in the platform on one side of the retaining wall and in the soil layer of the top concrete box to green the wall.

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