A vertical panel reinforced retaining wall structure

Abstract

This utility model relates to a vertical panel reinforced retaining wall structure, belonging to the field of geotechnical technology. The structure includes a surface layer composed of vertical panels and a geogrid-reinforced wall. The vertical panels are cast-in-place concrete panels with a bidirectional geogrid vertically installed at their center. The reinforced wall consists of alternating layers of unidirectional geogrid and fill material. A gravel layer is placed between the panel and the reinforced wall. The unidirectional geogrid extends through the gravel layer into the panel and is connected to the bidirectional geogrid by cable ties. Anchor steel bars are installed at the connection points and anchored into the gravel layer. This structure effectively enhances the reliability and integrity of the connection between the panel and the reinforcement through a dual connection method, and is simple to construct and has good durability.

Description

Technical Field

[0001] This utility model belongs to the field of geotechnical technology, and in particular relates to a vertical panel type reinforced retaining wall structure. Background Technology

[0002] Retaining walls, a widely used structural form in civil engineering, primarily function to support soil, prevent soil slippage and collapse, and thus maintain slope stability. Their applications cover infrastructure construction in areas such as highways, railways, water conservancy, and municipal works, playing a crucial role in ensuring project safety and improving land use efficiency. However, with the continuous expansion of modern engineering construction scale and the increasing technical requirements, traditional retaining wall structures have gradually revealed certain limitations in terms of material consumption, construction efficiency, environmental impact, and long-term service performance. Common types of traditional retaining walls include gravity retaining walls and cantilever retaining walls, which mainly resist earth pressure acting on the wall through their own weight or structural stiffness. However, these structures often suffer from problems such as heavy weight, long construction periods, high requirements for foundation bearing capacity, low material utilization, and significant environmental disturbance during construction, making it difficult to fully meet the demands of green, efficient, and sustainable development in modern engineering.

[0003] To address the aforementioned issues, reinforced soil retaining wall technology has emerged and gradually developed into a new type of retaining structure system with broad application prospects. This technology involves laying reinforcing materials (such as geogrids and geotextiles) with a certain tensile strength into the fill soil. Utilizing the interfacial friction between the reinforcing material and the fill soil, the overall shear strength and deformation modulus of the soil are enhanced, thereby effectively improving the stability and bearing capacity of the structure. Compared to traditional retaining walls, reinforced soil retaining walls have advantages such as lightweight structure, convenient construction, lower cost, and strong adaptability, and have been widely applied in various engineering fields. However, conventional reinforced soil retaining wall structures still have some problems: (1) Insufficient reliability of the connection between the panel and the stiffener: Existing structures mostly use metal connectors to fix the panel and the stiffener. However, this type of connection is easily affected by environmental corrosion. After corrosion, the mechanical properties of the connection nodes tend to degrade over time, which in turn affects the durability and safety of the overall structure.

[0004] (2) Weak connection structure between panel units: For facade assembled reinforced soil retaining walls, the panels are usually connected by simple mechanical methods such as bolts and pins. The node structure lacks sufficient bearing capacity and is prone to local separation or even overall instability under external force, posing potential safety hazards.

[0005] (3) Construction process limitations lead to resource waste: Traditional panel construction often uses wire mesh sprayed concrete process, which not only makes it difficult to control the construction accuracy, but also has a high material loss rate, resulting in unnecessary economic cost increases, and does not conform to the current development direction of green building.

[0006] Therefore, conducting systematic research and technological improvements to address the above issues has significant theoretical value and engineering practical significance for enhancing the structural performance, construction efficiency, and environmental adaptability of reinforced soil retaining walls. Summary of the Invention

[0007] The purpose of this utility model embodiment is to provide a vertical panel-type reinforced retaining wall structure, which effectively solves key technical problems such as poor reliability of the connection between the panel and the reinforcement, weak connection between panel units, and serious concrete waste during construction, thereby improving the overall stability, construction efficiency and environmental adaptability of the structure.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is a vertical panel reinforced retaining wall structure, including a surface layer and a geogrid reinforced wall; the surface layer is composed of vertical panels, which are cast concrete panels; a bidirectional geogrid is vertically arranged in the center of the interior of the vertical panel; the geogrid reinforced wall is composed of alternating layers of unidirectional geogrid and filler material; a gravel layer is provided between the vertical panel and the geogrid reinforced wall; the unidirectional geogrid passes through the gravel layer and extends to the position of the bidirectional geogrid in the vertical panel, and is connected to the bidirectional geogrid by cable ties; the extension section of the unidirectional geogrid is also provided with anchoring steel bars at the fixing points on the bidirectional geogrid, the anchoring steel bars passing through the fixing points and anchored inside the gravel layer.

[0009] Furthermore, the crushed stone layer is composed of rectangular woven bags filled with single-graded crushed stone.

[0010] Furthermore, the unidirectional geogrid is arranged horizontally, and the upper and lower layers are connected by connecting rods, and the filler layer is plain fill soil.

[0011] Furthermore, both the unidirectional geogrid and the connecting rod are made of high-density polyethylene.

[0012] Furthermore, the distance between the fixed points of the extension sections of the upper and lower unidirectional geogrids on the bidirectional geogrid 1 is equal to the distance between the upper and lower unidirectional geogrids.

[0013] Furthermore, each anchoring steel bar is spaced 1m-1.5m vertically along the geogrid-reinforced wall and 1m-2m horizontally.

[0014] Furthermore, the extension section of the unidirectional geogrid is fixedly connected to the outer wall of the upright panel by a cable tie at the fixing point on the bidirectional geogrid, and each pair of adjacent fixing points shares a cable tie cap.

[0015] Furthermore, on the outer wall of the upright panel, the spacing between the strip caps is equal to the distance between the anchor bars, but the positions of the strip caps and the anchor bars are staggered.

[0016] Furthermore, the thickness of the upright panel is 0.2-0.3m.

[0017] Compared with existing technologies, the beneficial effects of this utility model are as follows: This utility model uses cable ties to fix the bidirectional steel-plastic geogrid, achieving a geogrid fixing process that keeps the bidirectional steel-plastic geogrid vertical and taut, thereby achieving the vertical reinforcement effect of the panel and significantly improving the overall mechanical properties of the panel. The connection between the panel and the reinforced retaining wall adopts a dual connection method of anchoring steel bars and back-wrap geogrid, combined with cast-in-place concrete panel construction, effectively enhancing the structural reliability and integrity of the connection. After the cast-in-place concrete is formed, this dual connection structure effectively wraps the anchoring steel bars and back-wrap geogrid, significantly reducing their risk of corrosion from the external environment and improving the durability of the structure. The cast-in-place concrete upright panel combined with the cable tie-fixed geogrid fixation adopted in this utility model greatly simplifies the panel construction process, significantly improves construction efficiency, and avoids the traditional complex prefabrication and installation process of retaining wall panels. The vertically taut steel-plastic geogrid effectively enhances the overall rigidity and stability of the panel, solving the technical problem of easy loosening of the connection between the panel and the retaining wall in existing technologies. Meanwhile, the formwork steel plates used for cast-in-place molding can be reused, significantly reducing the consumption of engineering materials and construction costs. The vertical panel of this invention forms a mechanical interlock with the pre-reserved length of geogrid through anchoring steel bars, and achieves rigid fixation with cable ties, constructing a multi-layered synergistic connection system between the panel and the reinforced body, significantly improving the overall integrity and long-term performance of the structure. Furthermore, this invention employs a composite reinforcement system composed of bidirectional steel-plastic geogrid and unidirectional geogrid. It fully utilizes the uniform stress distribution characteristic of bidirectional geogrid in the plane to enhance the overall integrity of the panel, while combining the high-strength mechanical properties of unidirectional geogrid in the main stress direction to achieve a synergistic reinforcement effect, thereby significantly improving the overall stability, deformation resistance, and service life of the retaining wall structure. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a structural diagram of a vertical panel-type reinforced retaining wall according to this embodiment; Figure 2 This is a diagram showing the cross-sectional arrangement of the anchoring reinforcement bars in this embodiment; Figure 3 This is a schematic diagram of a bidirectional geogrid in this embodiment; Figure 4 This is a side sectional view of the upright panel type and geogrid reinforced wall in this embodiment; Figure 5 This is a front sectional view of the upright panel-type reinforced retaining wall structure in this embodiment.

[0020] In the diagram, 1. Bidirectional geogrid; 2. Backfill section geogrid; 3. Connecting rod; 4. Single-grade crushed stone; 5. Rectangular woven bag; 6. Unidirectional geogrid; 7. Cable tie; 8. Hole; 9. Vertical panel; 10. Anchoring steel bar; 11. Geogrid reinforced wall. Detailed Implementation

[0021] like Figures 1-5 This embodiment provides a vertical panel type reinforced retaining wall structure, including a surface layer and a geogrid reinforced wall 11; the surface layer is composed of vertical panels 9, the vertical panels 9 are cast concrete panels, and a bidirectional geogrid 1 is vertically arranged in the center of the interior of the vertical panels 9.

[0022] In some specific embodiments, the geogrid reinforced wall 11 is composed of alternately laid unidirectional geogrids 6 and filler layers; the unidirectional geogrids 6 are arranged horizontally, and the upper and lower layers are connected by connecting rods 3; the filler layer is plain fill soil; both the unidirectional geogrids 6 and the connecting rods 3 are made of high-density polyethylene material.

[0023] In some specific embodiments, a crushed stone layer is provided between the upright panel 9 and the geogrid reinforced wall 11; the crushed stone layer is made of rectangular woven bags 5 filled with single-grade crushed stone 4.

[0024] In some specific embodiments, the unidirectional geogrid 6 passes through the gravel layer and extends to the position of the bidirectional geogrid 1 within the upright panel 9, and is connected to the bidirectional geogrid 1 by cable ties 7 for fixation.

[0025] In some specific implementations, the distance between the fixed points of the extension sections of the upper and lower unidirectional geogrids 6 on the bidirectional geogrid 1 is equal to the distance between the upper and lower unidirectional geogrids 6.

[0026] In some specific embodiments, the extension section of the unidirectional geogrid 6 is further provided with anchoring steel bars 10 at the fixing point on the bidirectional geogrid 1. The anchoring steel bars 10 pass through the fixing point and are anchored inside the crushed stone layer to achieve overall structural stability.

[0027] In some possible implementations, each anchoring steel bar 10 is spaced 1m-1.5m vertically along the geogrid reinforced wall 11 and 1m-2m horizontally.

[0028] In some specific embodiments, the extension of the unidirectional geogrid 6 is fixedly connected to the outer wall of the upright panel 9 by a tie band at the fixing point on the bidirectional geogrid 1, and each two adjacent fixing points share a tie band cap; on the outer wall of the upright panel 9, the spacing between the tie band caps is equal to the spacing between the anchoring steel bars 10, but the positions of the tie band caps and the anchoring steel bars 10 are staggered.

[0029] In some specific embodiments, the unidirectional geogrid 6 in this embodiment is of type TGDG-80 (high-density polyethylene, HDPE), with a tensile strength ≥80kN / m, a vertical reinforcement spacing of 0.5m, and the length of the reverse-wrap section geogrid is 1.5-2.0 times the spacing of the unidirectional geogrid 6. The length of the unidirectional geogrid 6 and the length of the bidirectional geogrid 1 are determined according to the actual needs of the project. The bidirectional geogrid 1 is of type GSL-50, with a nominal tensile strength of ≥50kN / m in both longitudinal and transverse directions, and its usage matches the height of the panel per linear meter. The concrete vertical panel 9 is of type C30; the panel thickness is 0.2-0.3m. Figure 2 As shown, the anchoring steel bars 10 are arranged in a staggered pattern, evenly covering the entire panel area in both horizontal and vertical directions, effectively avoiding stress concentration. This arrangement in this embodiment can more efficiently transfer earth pressure to the reinforced body, significantly improving the overall load-bearing capacity and stability of the structure.

[0030] Vertical spacing: 1.0~1.5m, horizontal spacing: 0.5m. Anchoring depth not less than 0.6m, model: HRB400 Φ16mm, the amount used is determined according to the actual project (height and length of retaining wall).

[0031] In some specific embodiments, the geogrid-reinforced wall 11 is formed by alternating pressing of geogrid and filler layers. The geogrid part is made of unidirectional geogrid 6, and the upper and lower unidirectional geogrids 6 are connected by connecting rods 3. The filler layer is plain fill soil, and the materials of the unidirectional geogrid 6 and the connecting rods 3 are high-density polyethylene.

[0032] The geogrid-reinforced wall 11 with a backfill is connected to the vertical panel 9 via a layer of crushed stone. Specifically, the vertical panel 9 is connected to the reserved backfill section geogrid 2 via pre-embedded anchor steel bars 10, thereby fixing the rectangular woven bag 5 and forming a stable wall slope structure together with the single-grade crushed stone 4. The single-grade crushed stone 4 also serves as temporary support and drainage.

[0033] The construction method of the vertical panel 9-type reinforced retaining wall in this embodiment includes the construction of the vertical panel 9 and the geogrid reinforced wall 11. The construction of the vertical panel 9 is a modular cast-in-place concrete steel plate slipform construction. The outer formwork of the vertical panel 9 is an upright steel plate slipform, and the inner formwork is a slope formed by rectangular woven bags 5 and single-grade crushed stone 4. The inner side of the vertical panel 9 includes a layer of upright bidirectional geogrid 1 to reinforce the vertical panel 9. The construction method of the vertical panel 9-type reinforced retaining wall includes the following steps: foundation excavation → construction of reinforced soil retaining wall → construction of cast-in-place vertical panel 9 → construction of reinforced soil retaining wall → construction of cast-in-place vertical panel 9, until the retaining wall is constructed to the specified height and the project is completed.

[0034] Before constructing the vertical panel type 9 reinforced retaining wall in this implementation method, based on the designed reinforced retaining wall plan, site topographic map, cut and fill volume, soil parameters, and other relevant data, the following information is determined through stability calculations: 1. The slope and height of the reinforced retaining wall; 2. Model, length, vertical spacing, wrapping length, and quantity of unidirectional geogrid 6; 3. Model, length, and quantity of bidirectional geogrid 1; 4. Model and quantity of concrete vertical panels 9; 5. Arrangement, type and quantity of anchoring steel bars 10.

[0035] In some specific implementation methods, the construction steps of the vertical panel type 9 reinforced retaining wall are as follows: (1) Foundation earthwork excavation: Survey and set out, excavate and level according to the set-out position, and excavate the foundation bed to the elevation of the bottom grid laying; (2) Construction of reinforced soil retaining wall and vertical panel 9: 1. Laying the first layer of reinforcement: Cut the bottom layer of geogrid as required, lay it in the specified position, and reserve the length required for the back-wrapped section of geogrid 2 and the upper back-wrapped section of unidirectional geogrid 6; when laying unidirectional geogrid 6, the roll length direction should be perpendicular to the edge line, spread it smoothly, pull it tight to avoid wrinkles, and fix it to the ground with U-shaped nails every 1.5-2.0m on the laid unidirectional geogrid 6; wherein: the unidirectional geogrid 6 is high-density polyethylene, and its longitudinal tensile strength is ≥80kN / m; the U-shaped nails are galvanized steel nails with a diameter of 6mm, and the nailing depth is not less than 300mm; the reserved length of the back-wrapped section of geogrid is 1.5-2.0 times its laying layer height.

[0036] 2. Layered compaction of backfill: On the bottom layer of geogrid and geotextile, fill the backfill using a bucket excavator or a bulldozer with a bucket, and then compact it in layers using compaction machinery. There should be at least a 15cm thick layer of backfill between the machine tracks and the unidirectional geogrid 6; until the height of the first compacted layer is 0.5m, and the height of each subsequent compacted layer is 0.5m. The backfill material is well-graded plain fill with a particle size not exceeding 50mm; the excitation force of the vibratory roller is not less than 300kN; and the overlap width of adjacent roller tracks is not less than 1 / 3 of the roller width.

[0037] 3. Lay rectangular woven bags 5 alternately along the longitudinal direction in the reverse-wrapped section of the geogrid. Fill the rectangular woven bags 5 with single-grade crushed stone 4 with a particle size of 5-20mm, so that the filled rectangular woven bags 5 are arranged in a quincunx pattern. Pass the reverse-wrapped section of geogrid 2 through the bidirectional geogrid 1 for 1-2m. Use high-strength polyester cable ties 7 to fix the reverse-wrapped section of geogrid 2 to the bidirectional geogrid 1, and leave 7 cable ties for 1m-1.2m. Fold the reverse-wrapped section of geogrid back and lay it on the surface of the first layer of compacted soil, and fix it with U-shaped nails at intervals of 1.5-2.0m.

[0038] 4. Lay the second layer of unidirectional geogrid 6 on the first layer of compacted fill, reserving the length required for the geogrid back-wrapping section and the length required for the geogrid back-wrapping section. The length of the back-wrapping section of geogrid 2 is 1.5-2.0 times the height of its laying layer. Connect the top of the first layer and the bottom of the second layer of geogrid with connecting rods 3. The connecting rods 3 are made of high-density polyethylene rods with a diameter of 12mm. Pass the back-wrapping section of geogrid 2 through the top of the pre-laid bidirectional geogrid 1, and use cable ties to lock and fix the back-wrapping section of geogrid 2 to the bidirectional geogrid 1. Reserve 7 cable ties with a length of 0.4-0.6m for subsequent connection.

[0039] 5. Steel Plate Slipform Construction: A steel plate slipform is constructed using a steel plate with a thickness of 10±0.5mm. The standard dimensions of the steel plate slipform are: height 1000±10mm and length 2000±20mm. Holes 8, 2-3mm larger in diameter than the cable ties 7, are made 100±5mm from the top of the steel plate slipform. The center-to-center spacing of the holes 8 is 200±5mm. The steel plate slipform is vertically installed 200-300mm horizontally from the surface of the bidirectional geogrid 1. A dedicated fixing device is used to ensure that the verticality deviation of the steel plate slipform is ≤3‰. Two pre-reserved cable ties 7 are threaded into the same hole 8, and a pre-tension of 5-8kN is applied to tighten the bidirectional geogrid 1. The cable ties 7 are then locked to the top of the steel plate slipform using a cable cap with a torque of 5-8N·m. The steel plate slipform is made of Q235B steel plate; the machining accuracy of the holes 8 is ±0.5mm; and the dedicated fixing device includes an adjustable support frame and a vertical calibrator.

[0040] 6. Construction of cast-in-place concrete vertical panel 9: C25-C30 grade concrete is used for layered pouring. The pouring height is controlled to the lower edge of the steel plate slipform hole 8. During the pouring process, the concrete slump is kept within the range of 80-100mm. It is cured for 24±2 hours under an ambient temperature of 20±5℃. When the concrete compressive strength reaches more than 5MPa, the demolding operation is carried out. The roll cap at the hole 8 is removed using a special cutting tool. A hydraulic jacking device is used to separate the steel plate slipform from the concrete panel with a jacking force of 0.5-1.0MPa. The demolding speed is controlled within the range of 5-10mm / s.

[0041] 7. Repeat steps 1-6 above until all retaining wall construction is completed.

[0042] Compare the method of this embodiment with existing methods: Compared to the traditional shotcrete process with wire mesh, the steel plate slipform casting method used in this embodiment reduces cement consumption by 35% to 42% during the construction of the vertical panel 9, and lowers the concrete loss rate from 12% to 15% in the traditional process to 3% to 5%. This embodiment avoids the waste caused by rebound of shotcrete through modular casting and precise steel plate slipform forming, while also optimizing the reuse rate of formwork. Furthermore, supplementary experimental data from this embodiment, compared with traditional structures, shows a 25% improvement in deformation resistance and a 30% increase in construction efficiency. This embodiment simplifies the installation steps of the vertical panel 9 by using cable ties 7 to fix the grid. Experimental verification shows that the demolding time of the steel plate slipform used in this embodiment is 60% to 70% shorter than that of traditional wooden formwork, and the demolding time for a single module can be controlled within 30 minutes.

[0043] This embodiment uses high-strength polyester cable ties 7 to fix the geogrid 2 in the back-wrap section and the bidirectional steel-plastic geogrid, replacing traditional metal connectors (such as bolts and reinforcing bars), thus solving the durability problem caused by metal corrosion. Secondly, the double fixing using anchoring steel bars 10 and cable ties 7 creates a synergistic effect of mechanical interlocking and rigid locking, significantly improving the integrity of the vertical panel 9 and the geogrid-reinforced wall 11. The bidirectional geogrid 1 is installed on the inner side of the vertical panel 9 (fixed with cable ties 7 in a taut state), dispersing stress through its uniform stress characteristics and avoiding connection failure caused by localized stress concentration. The geogrid-reinforced wall 11 uses rectangular woven bags 5 filled with single-graded crushed stone 4, serving both as temporary support and drainage, simplifying the design of traditional drainage blind ditches and reducing the risk of seepage damage.

[0044] This embodiment uses anchor steel bars 10 and geogrid 2 to double connect the panel and the reinforced retaining wall, and adopts cast-in-place panels, which makes the connection more solid and the overall performance better. After being cast in place, the anchor steel bars 10 and geogrid 2 are not easily affected by environmental corrosion.

[0045] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model are included within the scope of protection of this utility model.

Claims

1. A vertical panel-type reinforced retaining wall structure, characterized in that, The structure includes a surface layer and a geogrid-reinforced wall (11); the surface layer is composed of a vertical panel (9), which is a cast concrete panel; a bidirectional geogrid (1) is vertically installed in the center of the vertical panel (9); the geogrid-reinforced wall (11) is composed of alternately laid unidirectional geogrids (6) and a filler layer; a gravel layer is provided between the vertical panel (9) and the geogrid-reinforced wall (11); the unidirectional geogrid (6) passes through the gravel layer and extends to the position of the bidirectional geogrid (1) in the vertical panel (9), and is connected to the bidirectional geogrid (1) by a cable tie (7); the extension section of the unidirectional geogrid (6) is also provided with anchoring steel bars (10) at the fixing point on the bidirectional geogrid (1), and the anchoring steel bars (10) pass through the fixing point and are anchored inside the gravel layer.

2. The upright panel-type reinforced retaining wall structure according to claim 1, characterized in that, The crushed stone layer is made up of rectangular woven bags (5) filled with single-grade crushed stone (4).

3. The upright panel-type reinforced retaining wall structure according to claim 1, characterized in that, The unidirectional geogrid (6) is arranged horizontally, and the upper and lower layers are connected by connecting rods (3). The filler layer is plain fill soil.

4. The upright panel-type reinforced retaining wall structure according to claim 3, characterized in that, The unidirectional geogrid (6) and connecting rod (3) are both made of high-density polyethylene.

5. The upright panel-type reinforced retaining wall structure according to claim 1, characterized in that, The distance between the extensions of the upper and lower unidirectional geogrids (6) and the fixed points on the bidirectional geogrid (1) is equal to the distance between the upper and lower unidirectional geogrids (6).

6. The upright panel-type reinforced retaining wall structure according to claim 1, characterized in that, Each anchoring steel bar (10) is set at a vertical interval of 1m-1.5m along the geogrid reinforced wall (11); and at a horizontal interval of 1m-2m.

7. The upright panel-type reinforced retaining wall structure according to claim 1, characterized in that, The extension of the unidirectional geogrid (6) is fixed to the outer wall of the upright panel (9) by means of cable ties (7) and grommets, with each pair of adjacent fixing points sharing a grommets.

8. The upright panel-type reinforced retaining wall structure according to claim 7, characterized in that, On the outer wall of the upright panel (9), the distance between the strip caps is equal to the spacing between the anchor bars (10), but the positions of the strip caps and the anchor bars (10) are staggered.

9. The upright panel-type reinforced retaining wall structure according to claim 1, characterized in that, The thickness of the upright panel (9) is 0.2-0.3m.

Images