Construction method of prestressed reinforced soil embankment

Abstract

The invention relates to the technical field of road construction, and discloses a prestressed reinforced soil embankment construction method which comprises the steps of site leveling, wall surface foundation construction, retaining structure and embankment core construction, tie bar net layer construction, prestressed rib net layer construction, cast-in-place outer wall surface and wall top pressing plate construction, formwork removal and prestressed tensioning. Each layer of the embankment filler and each layer of the reverse osmosis filler can be compacted, the compaction degree of the embankment filler and the reverse osmosis filler is improved, and due to the fact that the reinforced net reversely wraps the geotechnical bags of the geotechnical bag layer and then extends into the embankment core, the integrity and stability of the embankment can be improved. The wall face foundation supports the geotechnical bag blocking body and the cast-in-place outer wall face, the reinforced net plays a role in connecting the embankment core and the geotechnical bag blocking body together, the tie bar net plays a role in connecting the embankment core and the cast-in-place outer wall face together, and the embankment core and the cast-in-place outer wall face are connected together through the pressure plate, the prestressed rib net and the anchor head. The integrity and the stability of the embankment are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of road construction, in particular to a construction method of a prestressed reinforced earth embankment. Background Art

[0002] Anchor plate retaining walls and tension retaining walls are common forms of embankment support. The walls of traditional anchor plate retaining walls are usually assembled from prefabricated plates or modules, or directly adopt a wall-less reverse-wrapped anchor plate retaining wall structure. Traditional anchor plate retaining walls have the following disadvantages: (1) The compaction of the filler near the wall surface is insufficient, which is not conducive to the stability and deformation control of the retaining wall; (2) The assembled wall surface is not integral, and it is a typical flexible retaining wall, which may cause large local deformation or even collapse and failure of the wall surface; (3) Unlike prestressed soil, which actively applies stress, the reinforcement of traditional reinforced soil is passively stressed. The price of the reinforcement material is the relative deformation (trend) of the reinforcement / soil, and the deformation of the reinforcement / soil and the embankment is large. The stability and bearing capacity of the double-tension retaining wall are both high, but it has the following disadvantages: (1) When the embankment width is large, the force transmission path of the retaining wall becomes longer, and the lateral soil stress level is unevenly distributed. The soil stress level at the position far from the retaining wall is significantly lower than that at the wall panel, which causes large deformation in the middle of the road and reduces the bearing capacity. (2) The double-tension retaining wall relies on the tie bars connecting the two retaining walls to provide balancing force. Once the tie bars are damaged, the retaining walls on both sides will be damaged at the same time, which has a high risk factor. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a construction method for a prestressed reinforced earth embankment, which produces an embankment with small deformation, high integrity and stability.

[0004] A construction method for a prestressed reinforced earth embankment according to an embodiment of the present invention includes the following steps.

[0005] Site leveling: Level the site and compact the site in the designed embankment area; Wall foundation construction: excavating a foundation trench for the wall foundation outside the embankment area and constructing the wall foundation; Construction of retaining structure and embankment core: one end of a reinforcement net is placed in the embankment area, the other end of the reinforcement net extends to above the wall foundation, a plurality of geobags filled with geotextile fillers are stacked on the reinforcement net at a position corresponding to the wall foundation to form a geobag layer, the other end of the reinforcement net is wrapped around the geobag layer, embankment fillers are filled in the embankment area, reverse osmosis fillers are filled in the area between the embankment fillers and the geobag layer, and the reverse osmosis fillers and the embankment fillers are compacted to obtain a retaining structure layer and an embankment core layer; Construction of the reinforcement mesh layer: When the height of the retaining structure layer and the embankment core layer reaches the designed height of the reinforcement mesh layer, the reinforcement mesh is first laid on the retaining structure layer and the embankment core layer, and the reinforcement mesh is extended to the outside of the geobag layer, thereby completing the construction of one reinforcement mesh layer to obtain the reinforcement mesh layer; Construction of prestressed tendon mesh layer: when the height of the retaining structure layer and the embankment core layer reaches the designed height of the prestressed tendon mesh layer, first bury at least a pair of pressure plates in the embankment filler, and then lay prestressed tendons on the retaining structure layer and the embankment core layer, one end of the prestressed tendon is connected to the pressure plate, and the other end of the prestressed tendon passes through the pressure plate on the opposite side and extends to the outside of the designed cast-in-place exterior wall surface, the prestressed tendon located on the left side of the embankment area is connected to the pressure plate located on the right side of the embankment area, and the prestressed tendon located on the right side of the embankment area is connected to the pressure plate located on the left side of the embankment area, and the construction of one layer of prestressed tendon mesh layer is completed to obtain a prestressed tendon mesh; Construction of cast-in-place exterior wall and wall top plate: on the basis of the wall, reinforcement of the cast-in-place exterior wall and wall top plate is arranged on the outer side of the geobag layer, the reinforcement is connected to the reinforcement mesh, a template is arranged on the outer side of the reinforcement, the template is provided with an avoidance hole, the prestressed tendons are passed through the avoidance hole and extend to the outside of the template, and then concrete is poured in the template to obtain the cast-in-place exterior wall and wall top plate; Removing the formwork and prestressing tensioning: after the concrete curing is completed, the formwork is removed, the prestressed tendons extending outside the formwork are connected to the anchor heads, and prestress is applied to the prestressed tendons. The left and right sides of the same embankment area are constructed simultaneously, and finally the anchors are sealed.

[0006] It has at least the following beneficial effects: During construction, the embankment already possesses self-stability even before prestressing is tightened, thanks to the reverse-wrapped connection of the reinforced mesh and the initial stabilizing anchoring force provided by the tensioning mesh. This self-stability ensures that both the embankment fill and the reverse-seepage fill near the cast-in-place exterior wall are effectively compacted during construction. After prestressing is tightened, the ultimate anchoring force and stiffness of the dual pressure zones between the left and right pressure plates increase significantly under the action of prestressing, greatly enhancing the embankment's stability and reducing its deformation under additional loads. Compared to traditional double-tension retaining wall embankments, this embankment offers a more even distribution of soil pressure and a higher degree of safety redundancy. Even after the prestressing tendons on one side are damaged, the embankment remains stable.

[0007] Each layer of the embankment filler and each layer of the reverse osmosis filler can be compacted to improve the compaction of the embankment filler and the reverse osmosis filler. Moreover, since the reinforced mesh wraps around the geobag layer and extends into the embankment core formed by the multiple embankment core layers, the integrity and stability of the embankment can be improved. The wall foundation supports the geobag retaining body and the cast-in-place exterior wall. The reinforced mesh connects the embankment core and the geobag retaining body together. The tensioned mesh connects the embankment core and the cast-in-place exterior wall together. The embankment core and the cast-in-place exterior wall are connected together by pressure plates, prestressed mesh, and anchor heads, ensuring the integrity and stability of the embankment.

[0008] According to some embodiments of the present invention, the initial steps of constructing the retaining structure and the embankment core include installing a plurality of drainage pipes at the bottom of the geobag, with one end of the drainage pipe extending to the bottom of the reverse osmosis filler and the other end of the drainage pipe extending to the outside of the cast-in-place exterior wall.

[0009] According to some embodiments of the present invention, in the construction step of the prestressed tendon mesh layer, all the pressure plates are provided with a first through hole, the prestressed tendons located on the left side of the embankment pass through the first through hole of the pressure plate located on the left side of the embankment from the outside of the cast-in-place exterior wall on the left side and are connected to the pressure plate located on the right side of the embankment, and the prestressed tendons located on the right side of the embankment pass through the first through hole of the pressure plate located on the right side of the embankment from the outside of the cast-in-place exterior wall on the right side and are connected to the pressure plate located on the left side of the embankment.

[0010] According to some embodiments of the present invention, a plurality of pairs of pressure plates are provided according to the width of the embankment and the distribution of horizontal earth pressure between the left and right cast-in-place exterior walls.

[0011] According to some embodiments of the present invention, the prestressed tendons include multiple steel strands or prestressed steel bars, a protective tube is provided on the steel strands or the prestressed steel bars, and a lubricant is provided between the steel strands or the prestressed steel bars and the protective tube.

[0012] According to some embodiments of the present invention, the reinforcing mesh is a geosynthetic material or a metal material, and both ends of the reinforcing mesh are arranged between two upper and lower adjacent layers of the embankment core layer. The length of the reinforcing mesh after passing through the reverse osmosis filler and entering the embankment core layer is greater than 3m, and the interval between the two upper and lower adjacent layers of the reinforcing mesh is 0.3m-0.6m.

[0013] According to some embodiments of the present invention, the reinforcement mesh includes a plurality of steel bars arranged at intervals and perpendicular to the cast-in-place exterior wall surface, one end of the steel bar is connected to an L-shaped anchor, and the anchor is arranged between two upper and lower adjacent layers of the embankment core layer, and the other end of the steel bar is elbow-shaped and connected to the reinforcement of the cast-in-place exterior wall surface.

[0014] According to some embodiments of the present invention, the geobag is a geosynthetic material, and the geofill is soil, sand or crushed soil.

[0015] According to some embodiments of the present invention, the reverse osmosis filler is made of graded sand and gravel.

[0016] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which: Figure 1 A schematic diagram of a semi-longitudinal section of a prestressed reinforced earth embankment constructed according to an embodiment of the present invention; Figure 2 This is a schematic structural diagram of the geobag retaining body, reinforcement mesh and cast-in-place exterior wall of the prestressed reinforced earth embankment constructed in accordance with an embodiment of the present invention; Figure 3 This is a schematic structural diagram of the geobag retaining body, reinforcement mesh and tension mesh of the prestressed reinforced earth embankment constructed according to an embodiment of the present invention; Figure 4 Schematic diagram of the prestressed reinforcement mesh structure corresponding to the I-type prestressed retaining wall; Figure 5 Schematic diagram of the prestressed reinforcement mesh structure corresponding to the Type II prestressed retaining wall; Figure 6 Schematic diagram of the cross-sectional earth pressure distribution of the embankment corresponding to the anchor plate retaining wall, tension retaining wall, type I prestressed retaining wall and type II prestressed retaining wall.

[0018] Figure Number: Wall foundation 100; Reverse osmosis layer 200; Geobag retaining body 300; Reinforced mesh 400; Cast-in-place exterior wall 500; Reinforcement mesh 600; anchor 610; reinforcement 620; Prestressed tendon mesh 700; pressure plate 710; anchor head 720; prestressed tendon 730; Drain pipe 800; Wall top pressure plate 900. DETAILED DESCRIPTION

[0019] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0020] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0021] In the description of the present invention, "a plurality" refers to more than two, and "a number" refers to one, two, or more. The terms "first" and "second" are used solely to distinguish technical features and are not to be construed as indicating or implying relative importance, or as implicitly indicating the number of the technical features, or as implicitly indicating the order of the technical features.

[0022] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0023] Reference Figures 1 to 5 The present invention discloses a construction method of a prestressed reinforced earth embankment, which includes the following steps: site leveling step, wall foundation construction step, retaining structure and embankment core construction step, reinforcement mesh layer construction step, prestressed reinforcement mesh layer construction step, cast-in-place exterior wall and wall top pressure plate construction step, and formwork removal and prestressing tensioning step.

[0024] Site leveling: Level the site and compact the site in the designed embankment area; Wall foundation construction: excavate a foundation trench for the wall foundation 100 on the outside of the embankment area, and construct the wall foundation 100. The outside of the embankment area refers to the left and right sides of the embankment area. Retaining structure and embankment core construction: One end of the reinforcement net 400 is placed in the embankment area, and the other end of the reinforcement net 400 extends to the top of the wall foundation 100. A number of geobags filled with geotextile fillers are stacked on the reinforcement net 400 at positions corresponding to the wall foundation 100 to form a geobag layer. The other end of the reinforcement net 400 is wrapped with the geobag layer. The embankment area is filled with embankment fillers, and the area between the embankment fillers and the geobag layer is filled with reverse osmosis fillers. The reverse osmosis fillers and the embankment fillers are compacted to obtain a retaining structure layer and a embankment core layer. Reinforcement mesh layer construction: When the height of the retaining structure layer and the embankment core layer reaches the designed height of the reinforcement mesh layer, first lay the reinforcement mesh 600 on the retaining structure layer and the embankment core layer, and extend the reinforcement mesh 600 to the outside of the geobag layer, thus completing the construction of one reinforcement mesh layer and obtaining the reinforcement mesh layer; Construction of the prestressed tendon mesh layer: When the height of the retaining structure layer and the embankment core layer reaches the designed height of the reinforcement mesh layer, first bury at least a pair of pressure plates 710 in the embankment filler, and then lay the prestressed tendons 730 on the retaining structure layer and the embankment core layer. One end of the prestressed tendon 730 is connected to the pressure plate 710, and the other end of the prestressed tendon 730 passes through the pressure plate 710 on the opposite side and extends to the outside of the designed cast-in-place exterior wall. The prestressed tendon 730 on the left side of the embankment area is connected to the pressure plate 710 on the right side of the embankment area, and the prestressed tendon 730 on the right side of the embankment area is connected to the pressure plate 710 on the left side of the embankment area. The construction of one layer of prestressed tendon mesh is completed, and the prestressed tendon mesh 700 is obtained. Construction of cast-in-place exterior wall and top plate: Reinforcement for the cast-in-place exterior wall and top plate is installed on the wall foundation 100, corresponding to the outer side of the geobag layer. The reinforcement is connected to the reinforcement mesh 600. A formwork is installed on the outer side of the reinforcement. The formwork is provided with avoidance holes. Prestressed tendons 730 are inserted through the avoidance holes and extend outside the formwork. Concrete is then poured inside the formwork to obtain the cast-in-place exterior wall 500 and top plate 900. Removing the formwork and prestressing tensioning: After the concrete is cured, the formwork is removed, and the prestressed tendons 730 extending outside the formwork are connected to the anchor heads 720, and prestress is applied to the prestressed tendons 730. The left and right sides of the same embankment area are constructed symmetrically and synchronously, and finally the anchors are sealed.

[0025] After each retaining structure and embankment core construction step, the reinforcement mesh layer construction step is carried out. After multiple reinforcement mesh layer construction steps, the prestressed reinforcement mesh layer construction step is carried out. Then the retaining structure and embankment core construction steps are carried out again. And so on, a multi-layered reinforcement mesh 400 distributed vertically, a multi-layered reinforcement mesh 600 distributed vertically, and a multi-layered prestressed reinforcement mesh 700 distributed vertically are obtained. Then the cast-in-place exterior wall and wall top pressure plate construction steps are carried out. Finally, the formwork is removed and the prestressed tensioning construction steps are carried out. The multi-layered reverse osmosis fillers distributed vertically form the reverse osmosis layer 200, the multi-layered geobag layers distributed vertically form the geobag retaining body 300, the multi-layered retaining structure layers distributed vertically form a compact embankment retaining structure, and the multi-layered embankment core layers distributed vertically form a compact embankment core. The prestressed reinforced earth embankment is obtained by the construction method of the prestressed reinforced earth embankment.

[0026] Of course, the tensioning mesh 600 and the prestressed tendons 730 of the prestressed tendon mesh 700 can pass through the geobag layer wrapped at the other end of the reinforcement mesh 400.

[0027] The prestressed reinforced earth embankment includes a wall foundation 100, an anti-seepage layer 200, a geobag retaining body 300, a cast-in-place exterior wall 500, a multi-layer reinforcement mesh 400, a multi-layer tensioning mesh 600 and a multi-layer prestressed reinforcement mesh 700.

[0028] The wall foundation 100 is arranged at the outer bottom of the embankment area; the anti-osmosis layer 200 is arranged at the edge of the embankment area; the geobag barrier 300 is arranged on the outside of the anti-osmosis layer 200, and the geobag barrier 300 includes multiple layers of geobag layers, the geobags in the geobag layers are filled with fillers, and the multiple layers of geobag layers are stacked on the wall foundation 100 and are located on the outside of the anti-osmosis layer 200; one end of the multi-layer reinforcement net 400 is distributed up and down in the embankment core, and the other end of the multi-layer reinforcement net 400 is reversed to wrap several layers of geobag layers and extend into the embankment core; the cast-in-place external wall 500 is arranged on the wall foundation 100 and is located on the outside of the geobag barrier 300; one end of the multi-layer reinforcement net 600 is located in the embankment core, The other end of the multi-layer reinforcement mesh 600 passes through the anti-osmosis layer 200 and the geobag barrier 300, and the other end of the multi-layer reinforcement mesh 600 is connected to the reinforcement of the cast-in-place exterior wall 500; multiple pressure plates 710 are distributed up and down in the embankment core, and there are several pairs of pressure plates 710 at the same height. The prestressed tendons 730 on the left side of the embankment core are connected to the pressure plate 710 on the right side of the embankment core, and the prestressed tendons 730 on the right side of the embankment core are connected to the pressure plate 710 on the left side of the embankment core. The other end of the prestressed tendons 730 passes through the anti-osmosis layer 200 and the geobag barrier 300, and the other end of the prestressed tendons 730 are connected to the cast-in-place exterior wall 500 through the anchor head 720.

[0029] During the construction process, each layer of embankment filler and each layer of reverse osmosis filler can be compacted to improve the compaction degree of the embankment filler and the reverse osmosis filler. Moreover, since the geobags of the geobag layer are wrapped by the reinforcement net 400 and extend into the embankment core, the reinforcement net 400 can improve the local stability of the embankment.

[0030] The wall foundation 100 plays a supporting role, the reinforcement mesh 400 connects the embankment core and the geobag retaining body 300 together, and the tensioning mesh 600 connects the embankment core and the cast-in-place outer wall 500 together. The embankment core and the cast-in-place outer wall 500 are connected together through the pressure plate 710, the prestressed reinforcement mesh 700 and the anchor head 720 to ensure the integrity and stability of the embankment and improve the bearing capacity of the embankment.

[0031] During the construction process, the formwork used to shape the cast-in-place exterior wall 500 can be connected to the reinforcement mesh 600 to ensure the stability of the reinforcement and formwork of the cast-in-place exterior wall 500; after the cast-in-place exterior wall 500 is formed, under the tensioning action of the pressure plate 710, the prestressed reinforcement mesh 700 and the anchor head 720, all the fillers between the pressure plates 710 on the left and right sides and between the pressure plates 710 and the cast-in-place exterior wall 500 increase their strength and rigidity due to the lateral compressive stress, and provide the pressure plate 710 with a large ultimate pull-out resistance, thereby reducing the risk of failure of the prestressed reinforcement mesh 700, reducing the deformation of the retaining structure and the embankment core, and reducing the risk of embankment collapse.

[0032] The reinforcement mesh 400, the tie mesh 600, and the prestressed tendons 730 provide triple stability for the retaining structure. The reinforcement mesh 400 primarily ensures the local stability of the embankment behind the vertical geobag fill during construction. The tie mesh 600 ensures formwork stability during the cast-in-place exterior wall construction process and integrates the tie mesh 600 with the wall. Both meshes also play a role in maintaining the structural stability of the retaining structure during operation. The prestressed tendons 730 apply pretension to the cast-in-place exterior wall 500, ensuring the overall stability of the retaining structure.

[0033] The embankment area between two adjacent pressure plates 710 constitutes a double pressure zone, while the embankment area between the pressure plates 710 and the cast-in-place exterior wall 500 constitutes a single pressure zone. Under the action of the tensioned prestressed tendons 730, the two adjacent pressure plates 710 squeeze the filler in the double pressure zone, significantly increasing the strength and stiffness of the filler in the central part of the embankment area, thereby increasing the ultimate anchoring force of the pressure plates 710. When the width of the double pressure zone is small, as long as the prestressed tendons 730 and pressure plates 710 do not break, the theoretical ultimate anchoring force can be increased infinitely. Moreover, because the two cast-in-place exterior walls are not directly connected by prestressed tendons 730, failure of the prestressed tendons 730 on one side will not affect the embankment structure on the opposite side, thereby increasing safety redundancy and significantly increasing the overall safety factor of the embankment.

[0034] The single pressure zone stress model can be simplified as follows: the geobags wrapped around the reinforcement mesh 400 can ensure that the filler near the cast-in-place exterior wall 500 reaches a high degree of compaction. The reinforcement mesh 400 and the tie mesh 600 jointly ensure the stability of the construction of the cast-in-place exterior wall 500. The tie mesh 600 is connected to the reinforcement of the cast-in-place exterior wall 500, so that the cast-in-place exterior wall 500 is connected to the retaining structure and embankment core behind the wall, thereby strengthening the integrity and seismic resistance of the cast-in-place exterior wall 500. After the prestressed tendons 730 are tensioned, the stability of the cast-in-place exterior wall 500 is no longer controlled by the reinforcement mesh 400 and the tie mesh 600, but by the prestressed tendon mesh 700. At this time, the overall stability of the cast-in-place exterior wall 500, the bearing capacity of the embankment and its ability to resist deformation are significantly increased.

[0035] Reference Figure 1and Figure 4 A pair of pressure plates 710 are set in the left and right directions of the embankment area. The positions of the pair of pressure plates 710 are symmetrical with the center of the embankment, or the positions of the pair of pressure plates 710 are not symmetrical with the center of the embankment, which is an I-type prestressed retaining wall.

[0036] Reference Figure 5 Two pairs of pressure plates 710 are set in the left and right directions of the embankment area, which is a Type II prestressed retaining wall. The two pairs of pressure plates 710 include a pair of first pressure plates and a pair of second pressure plates. The positions of the pair of first pressure plates are symmetrical with the center of the embankment, or the positions of the pair of first pressure plates are not symmetrical with the center of the embankment, and the positions of the pair of second pressure plates are symmetrical with the center of the embankment, or the positions of the pair of second pressure plates are not symmetrical with the center of the embankment.

[0037] See also Figure 6 Schematic diagram of the earth pressure distribution in the cross section of the embankment corresponding to different retaining walls, including the embankments corresponding to anchor plate retaining walls, tension retaining walls, type I prestressed retaining walls, and type II prestressed retaining walls. The horizontal axis represents the width of the embankment, the wall positions on the left and right sides of the horizontal axis represent the installation locations of the cast-in-place exterior wall 500, the pressure plate positions represent the installation locations of the pressure plates 710 on the embankment, and the vertical axis represents the horizontal earth pressure. The greater the horizontal earth pressure, the greater the bearing capacity, integrity, and stability of the embankment. Compared with anchor plate retaining walls and tension retaining walls, the embankment corresponding to type I prestressed retaining walls has higher bearing capacity, integrity, and stability; compared with anchor plate retaining walls, tension retaining walls, and type I prestressed retaining walls, the embankment corresponding to type II prestressed retaining walls has higher bearing capacity, integrity, and stability.

[0038] Prestressed reinforced earth embankment has the following advantages: 1. Stronger integrity. The cast-in-place exterior wall 500 avoids the shortcomings of traditional assembled panels or reverse-wrapped anchor plate retaining walls, which have weak integrity and are prone to local failure or large deformation under rain or earthquake. The cast-in-place exterior wall 500 is subjected to stress as a whole, and has a stronger protective effect on materials such as the filler and reinforcement mesh 400 behind the wall.

[0039] 2. The backfill behind the wall is more compacted. The reinforcement mesh 400, which wraps around the earthbag layer and extends into the backfill, provides greater stability during construction. The cast-in-place exterior wall and top plate construction steps are completed after the backfill is placed and compacted. This prevents the reinforcement mesh 400 from excessively bending and stretching near the cast-in-place exterior wall 500 due to compaction, thereby preventing the mesh from weakening.

[0040] 3. Smaller deformation. Pairs of pressure plates 710 are arranged opposite to each other or distributed left and right, which can improve the strength and stiffness of the filler between the pressure plates 710 and the cast-in-place exterior wall 500, thereby providing a higher ultimate pull-out resistance. The prestressed tendons 730 tensioned between the cast-in-place exterior wall 500 and the pressure plates 710 can apply a greater pre-tension force. Compared with the embankment corresponding to the traditional anchor plate retaining wall, the embankment obtained by this construction method has a greater overall stiffness and smaller deformation.

[0041] 4. Higher safety. If the prestressed reinforcement of the traditional double-tension retaining wall structure fails, the retaining walls on both sides will collapse at the same time. In this method, the prestressed reinforcement mesh 700 connected to the left and right cast-in-place exterior walls 500 is relatively independent. The failure of the prestressed reinforcement mesh 700 on one side will not cause the cast-in-place exterior wall 500 on the other side to lose its anchoring force. Similarly, the prestressed reinforcement mesh 700 on one side will have less impact on the cast-in-place exterior wall 500 on the other side. Therefore, it is safer to resist local failure of the prestressed reinforcement mesh 700 and is more convenient for construction and later maintenance.

[0042] 5. Prestress loss is smaller. Compared with the traditional tension retaining wall, the length of each prestressed tendon 730 in this method is shorter and the compression range is reduced, thereby greatly reducing prestress loss.

[0043] The prestressed tendon mesh 700 includes multiple horizontally arranged prestressed tendons 730, with no fewer than two horizontally distributed prestressed tendons 730 connected to each pressure plate 710. Pairs of pressure plates 710 are arranged side by side, positioned within the embankment pressure zone between the opposing pressure plates 710 and the geobag retaining element 300, to ensure sufficient force applied by the embankment core to the pressure plates 710. The pressure plates 710 are rectangular reinforced concrete structures, with reinforcement at the anchor points to ensure the connection strength between the prestressed tendons 730 and the pressure plates 710, as well as the strength of the pressure plates 710 themselves.

[0044] It is conceivable that the prestressed tendon 730 and the pressure plate 710 are connected by another anchor head. The pressure plate 710 is provided with a mounting hole that passes through both sides of the pressure plate 710. The end of the prestressed tendon 730 passes through the mounting hole and is threadedly connected to the other anchor head. The other anchor head rests on the side of the pressure plate 710 that is away from the prestressed tendon 730.

[0045] The simultaneous construction of the retaining structure and embankment core enabled rapid embankment filling, sufficient compaction of various fill materials, and the casting of the exterior walls using 500-degree single-sided formwork. This leveraged the advantages of the 710-degree directional pressure plates, resulting in strong ultimate pullout resistance and overall stability. The retaining structure and embankment core offer excellent seismic resistance, high bearing capacity, minimal foundation bearing capacity requirements, and resistance to large deformation, thereby improving the quality of the embankment.

[0046] It can be imagined that during the construction steps of the retaining structure and the embankment core, a vibrating rod or a hand-held vibrating roller is inserted into the reverse osmosis filler near the cast-in-place outer wall to improve the compaction of the reverse osmosis filler at the cast-in-place outer wall, thereby obtaining a retaining structure layer and an embankment core layer.

[0047] Reference Figure 1 In some embodiments, the initial retaining structure and embankment core construction steps include arranging multiple drainage pipes 800 at the bottom of the geobag, with one end of the drainage pipe 800 extending to the bottom of the reverse osmosis filler, and the other end of the drainage pipe 800 extending to the outside of the geobag, and the length of the drainage pipe 800 extending to the outside of the geobag is greater than the thickness of the cast-in-place exterior wall 500. The thickness direction of the cast-in-place exterior wall 500 is the left-right direction. After the construction of the cast-in-place exterior wall 500 is completed, the other end of the drainage pipe 800 is connected to the outside of the cast-in-place exterior wall 500, and the water in the embankment core and the reverse osmosis layer 200 can be drained to the outside of the cast-in-place exterior wall 500 through the drainage pipe 800, thereby increasing the drainage speed of the embankment core and the reverse osmosis layer 200, ensuring the drainage effect of the embankment filler and the reverse osmosis filler, and further reducing the risk of deformation, settlement and collapse of the retaining structure and the embankment core.

[0048] Reference Figure 1 and Figure 2 In some of the embodiments, in the prestressed reinforcement mesh layer construction step, the pressure plate 710 located on the left side of the embankment area and the pressure plate 710 located on the right side of the embankment area are distributed left and right, and each pressure plate 710 is provided with a first through hole. The prestressed reinforcement mesh 700 located on the left side of the embankment area is passed through the first through hole of the pressure plate 710 located on the left side of the embankment area and is connected to the pressure plate 710 located on the right side of the embankment area. The prestressed reinforcement mesh 700 located on the right side of the embankment area is passed through the first through hole of the pressure plate 710 located on the right side of the embankment area and is connected to the pressure plate 710 located on the left side of the embankment area.

[0049] The first through hole is used to lay out the prestressed tendons 730 of the prestressed tendon mesh 700, and a double pressure zone is formed between the pressure plates 710 on the left and right sides, which is conducive to limiting the position of the pressure plates 710 so that the pressure plates 710 can apply sufficiently large tension to the prestressed tendon mesh 700 and the cast-in-place exterior wall 500.

[0050] Reference Figure 1 In some embodiments, during the construction of the cast-in-place exterior wall and the wall top plate, the reinforcement extends above the topmost geobag layer. During concrete pouring, a wall top plate 900 is formed on the geobag layer. The wall top plate 900 is positioned atop the geobag retaining element 300 and the cast-in-place exterior wall 500. Pressing downward on the geobag retaining element 300 and the cast-in-place exterior wall 500, the wall top plate 900 acts like a baffle. The height of the wall top plate 900 is no less than the height of the embankment.

[0051] In some embodiments, the prestressed reinforcement mesh 700 includes multiple steel strands or prestressed steel bars, which are prestressed bars 730. A protective tube is provided on the steel strands or prestressed steel bars, and a lubricant is provided between the steel strands or prestressed steel bars and the protective tube. The protective tube protects the steel strands or prestressed steel bars, and the lubricant lubricates the space between the steel strands or prestressed steel bars and the protective tube. The steel strands or prestressed steel bars can move in the protective tube to facilitate installation and adjustment of the steel strands or prestressed steel bars.

[0052] In some of the embodiments, the reinforcing mesh 400 is made of geosynthetics or metal materials, both ends of the reinforcing mesh 400 are arranged in the embankment core, at least one end of the reinforcing mesh 400 is arranged in the embankment core with a length greater than 3m, and the interval between two adjacent layers of reinforcing mesh 400 is 0.3m-0.6m, which ensures the connection between the embankment core and each layer of reinforcing mesh 400, improves the integrity between the embankment core and the retaining structure, and the strength of the embankment core and the retaining structure itself.

[0053] Reference Figure 1 In some embodiments, one end of the reinforcement mesh 600 is connected to an L-shaped anchor 610, which is arranged in the embankment core. The anchor 610 serves to reinforce the reinforcement mesh 600 in the embankment core. The other end of the reinforcement mesh 600 is elbow-shaped and connected to the reinforcement of the cast-in-place exterior wall 500. The elbow structure is conducive to strengthening the connection between the reinforcement mesh 600 and the cast-in-place exterior wall 500.

[0054] In some embodiments, the geobag layer includes multiple geobags, the geobags are geosynthetics, and the geofill is soil, sand or crushed soil. The geofill can be obtained nearby and has low cost, and the structure of the geobag layer formed by the geobags is relatively stable.

[0055] In some embodiments, the reverse osmosis filler is made of graded sand and gravel and has sufficient permeability and support.

[0056] In some embodiments, the cast-in-situ exterior wall 500 is a 0.2-0.5 m thin-wall structure.

[0057] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0058] Of course, the present invention is not limited to the above-mentioned embodiments. Those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A construction method for a prestressed reinforced earth embankment, characterized in that: The following steps are included: Site leveling: Level the site and compact the site in the designed embankment area; Wall foundation construction: excavating a foundation trench for the wall foundation (100) outside the embankment area, and constructing the wall foundation (100); Retaining structure and embankment core construction: one end of the reinforcement net (400) is arranged in the embankment area, the other end of the reinforcement net (400) extends to the top of the wall foundation (100), a plurality of geobags filled with geotextile fillers are stacked on the reinforcement net (400) at a position corresponding to the wall foundation (100) to form a geobag layer, the other end of the reinforcement net (400) is reversed to wrap the geobag layer, the embankment area is filled with embankment fillers, the area between the embankment fillers and the geobag layer is filled with reverse osmosis fillers, the reverse osmosis fillers and the embankment fillers are compacted to obtain a retaining structure layer and a embankment core layer; Construction of the reinforcement mesh layer: when the height of the retaining structure layer and the embankment core layer reaches the designed height of the reinforcement mesh layer, the reinforcement mesh (600) is first laid on the retaining structure layer and the embankment core layer, and the reinforcement mesh (600) is extended to the outside of the geobag layer, thereby completing the construction of one reinforcement mesh layer and obtaining the reinforcement mesh layer; Construction of prestressed tendon mesh layer: when the height of the retaining structure layer and the embankment core layer reaches the designed height of the prestressed tendon mesh layer, first bury at least one pair of pressure plates (710) in the embankment filler, and then lay prestressed tendons (730) on the retaining structure layer and the embankment core layer, one end of the prestressed tendon (730) is connected to the pressure plate (710), and the other end of the prestressed tendon (730) passes through the pressure plate (710) on the opposite side and extends to the outside of the designed cast-in-place exterior wall surface, the prestressed tendon (730) located on the left side of the embankment area is connected to the pressure plate (710) located on the right side of the embankment area, and the prestressed tendon (730) located on the right side of the embankment area is connected to the pressure plate (710) located on the left side of the embankment area, and the prestressed tendon (730) located on the right side of the embankment area is connected to the pressure plate (710) located on the left side of the embankment area, and the construction of one layer of prestressed tendon mesh layer is completed to obtain a prestressed tendon mesh (700); Construction of cast-in-place exterior wall and wall top pressure plate: reinforcement for the cast-in-place exterior wall and wall top pressure plate is arranged on the wall foundation (100) corresponding to the outer side of the geobag layer, the reinforcement is connected to the reinforcement mesh (600), a template is arranged on the outer side of the reinforcement, the template is provided with an avoidance hole, the prestressed tendons (730) are passed through the avoidance hole and extended to the outside of the template, and then concrete is poured in the template to obtain the cast-in-place exterior wall (500) and wall top pressure plate (900); Removing the formwork and prestressing tensioning: after the concrete curing is completed, the formwork is removed, the prestressed tendons (730) extending outside the formwork are connected to the anchor heads (720), and prestressing is applied to the prestressed tendons (730), wherein the left and right sides of the same embankment area are constructed simultaneously, and finally the anchors are sealed.

2. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: The initial steps of constructing the retaining structure and the embankment core include installing a plurality of drainage pipes (800) at the bottom of the geobag, one end of the drainage pipe (800) extending to the bottom of the reverse osmosis filler, and the other end of the drainage pipe (800) extending to the outside of the cast-in-place exterior wall (500).

3. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: During the construction step of the prestressed tendon mesh layer, a first through hole is provided on all the pressure plates (710); the prestressed tendons (730) located on the left side of the embankment pass through the first through hole of the pressure plate (710) located on the left side of the embankment from the outside of the cast-in-place exterior wall (500) on the left side and are connected to the pressure plate (710) located on the right side of the embankment; the prestressed tendons (730) located on the right side of the embankment pass through the first through hole of the pressure plate (710) located on the right side of the embankment from the outside of the cast-in-place exterior wall (500) on the right side and are connected to the pressure plate (710) located on the left side of the embankment.

4. A construction method for a prestressed reinforced earth embankment according to any one of claims 1 to 3, characterized in that: Several pairs of pressure plates (710) are provided according to the width of the embankment and the distribution of horizontal earth pressure between the cast-in-place exterior walls on the left and right sides.

5. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: The prestressed tendons (730) include a plurality of steel strands or prestressed steel bars, a protective tube is provided on the steel strands or the prestressed steel bars, and a lubricant is provided between the steel strands or the prestressed steel bars and the protective tube.

6. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: The reinforcing net (400) is made of geosynthetics or metal. Both ends of the reinforcing net (400) are arranged between two upper and lower adjacent layers of the embankment core layer. The length of the reinforcing net (400) that passes through the reverse osmosis filler and enters the embankment core layer is greater than 3m. The interval between the two upper and lower adjacent layers of the reinforcing net (400) is 0.3m-0.6m.

7. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: The reinforcement mesh (600) comprises a plurality of steel bars (620) arranged at intervals and perpendicular to the cast-in-situ exterior wall surface (500), one end of the steel bar (620) being connected to a plurality of rows of L-shaped anchors (610), the anchors (610) being arranged between two upper and lower adjacent layers of the embankment core, and the other end of the steel bar (620) being elbow-shaped and connected to the reinforcement of the cast-in-situ exterior wall surface (500).

8. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: The geobag is a geosynthetic material, and the geofill is soil, sand or crushed stone soil.

9. The construction method of a prestressed reinforced earth embankment according to claim 1, characterized in that: The reverse osmosis filler is made of graded sand and gravel.

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