RAP and aggregate partition composite reinforced retaining wall capable of controlling creep deformation and construction method of RAP and aggregate partition composite reinforced retaining wall
By filling the retaining wall with non-creep-resistant natural aggregate and RAP material in sections and using geogrids to form mechanical interlocking, the creep problem of RAP material in the high-stress zone of the retaining wall was solved, achieving long-term stability of the retaining wall and efficient utilization of RAP material.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YANGZHOU UNIV
- Filing Date
- 2026-03-13
- Publication Date
- 2026-04-21
AI Technical Summary
When using RAP materials to construct retaining walls, existing technologies often result in significant creep deformation in high-stress areas near the panel, leading to long-term safety hazards for the retaining walls and making it difficult to achieve the optimal configuration of reinforcement materials.
The retaining wall is divided into a rigid control zone and a resource absorption zone by adopting a zoned composite reinforcement method. Natural aggregate with no creep characteristics is used to fill the high stress zone, and the geogrid and RAP material form a mechanical interlock to form a smooth interface and limit creep deformation.
It effectively controlled creep deformation near the retaining wall panel, improved resistance to horizontal displacement, ensured the long-term stability of the retaining wall, and realized the large-scale disposal and environmentally friendly utilization of RAP materials.
Smart Images
Figure CN121897019A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the fields of road engineering and geotechnical engineering, specifically to a creep-controlled RAP and aggregate zoned composite reinforced retaining wall and its construction method. Background Technology
[0002] In recent years, a large amount of reclaimed asphalt pavement (RAP) has been generated in highway construction and maintenance projects in my country. In response to the green and low-carbon development policy, the resource utilization of RAP materials in roadbed and retaining wall fillers is an important research direction in the engineering field.
[0003] However, RAP material is coated with aged asphalt, which exhibits significant viscosity and temperature sensitivity. Current technologies attempting to use RAP as retaining wall fill typically employ a full-section homogeneous filling method (i.e., the entire retaining wall is filled with RAP). Research and engineering practice show that even with reinforcement using geogrids within the RAP, the area near the retaining wall panel (i.e., the sliding wedge zone within the active earth pressure rupture surface) is where shear stress and lateral earth pressure are highest. In this high-stress zone, pure RAP filler will still experience significant lateral creep deformation and vertical settlement under long-term constant loads, posing a threat to the long-term safety of the retaining wall.
[0004] Therefore, how to effectively solve the creep instability problem in the high-stress area near the panel while ensuring the large-scale disposal of RAP waste, and at the same time take into account the optimal configuration of reinforcing materials to avoid "over-reinforcement" or "under-reinforcement", is a technical problem that urgently needs to be solved in this field. Summary of the Invention
[0005] The purpose of this application is to provide a creep-controlled RAP and aggregate partitioned composite reinforced retaining wall and its construction method, so as to solve the above-mentioned defects caused by the prior art.
[0006] To achieve the above objectives, this application employs the following technical solution: In a first aspect, this application discloses a RAP and aggregate partitioned composite reinforced retaining wall for controlling creep, which includes... foundation; A retaining wall panel is fixedly installed on the foundation, and a filling area is provided between the retaining wall panel and the foundation; The filling area includes an adjoining rigid control area and a resource disposal area. The rigid control area is located on the side closer to the retaining wall panel. The rigid control area is provided with a first filler material with no creep characteristics, and the resource disposal area is provided with a second filler material. A smooth interface is formed at the junction of the first filler material and the second filler material. and geogrid, wherein the geogrid is placed inside the first filler and the second filler; In a further embodiment of this application, the retaining wall panel is perpendicular to the foundation and parallel to the interface. In a further embodiment of this application, the geogrid and the interface are perpendicular to each other in space.
[0007] In a further embodiment of this application, the multiple layers of geogrids are arranged vertically, with the spacing between adjacent geogrids being 0.12 to 0.18 m.
[0008] In a further embodiment of this application, the volume of the resource consumption area is greater than the volume of the rigid control area.
[0009] Secondly, this application also discloses a construction method for achieving the aforementioned RAP and aggregate zoned composite reinforced retaining wall for controlling creep, which includes the following steps: According to the foundation plane, a retaining wall panel is fixed on the foundation, and the foundation and the retaining wall panel form a filling area; A geogrid is laid on the foundation surface, and a movable baffle is embedded on the foundation surface to divide the filling area into a rigid control area and a resource consumption area. The rigid control zone is filled with a first filler material, and the resource consumption zone is filled with a second filler material; Remove the movable baffle and mechanically crush the first filler and the second filler to form a mechanical interlock at the interface, thus forming a composite reinforced retaining wall.
[0010] Further solutions to this application, When the rigid control zone and the resource consumption zone are filled with materials, the thickness of the first filler and the second filler are equal.
[0011] Further solutions to this application, Mechanical compaction of the first filler and the second filler includes: The compaction degree of both the first and second fillers is greater than 95% after mechanical compaction.
[0012] A further embodiment of this application also includes a first filler configuration; The first filler configuration includes a first filler with a screened particle diameter of less than 11 mm. Add water to the first filler material after screening and stir to adjust the moisture content of the first filler material to 5.1%.
[0013] Further solutions to this application, The geogrid is laid in multiple layers, including A geogrid is then laid on the upper surface of the composite reinforced retaining wall. The first filler and the second filler are then refilled and compacted. The process of laying the geogrid and the first filler and the second filler and compacting are repeated to complete the laying of multiple layers of the geogrid.
[0014] The beneficial effects of this application are as follows: The core driving force of retaining wall deformation comes from the high lateral stress in the sliding wedge zone behind the panel. This application replaces the second filler (RAP material) in this high-risk area with a first filler material (actually natural aggregate) that has no creep characteristics, effectively avoiding the engineering hazard of severe creep deformation in the high-stress zone near the retaining wall panel. The geogrid is firmly embedded in the high friction angle of the rigid crushed stone zone, which greatly improves the horizontal displacement resistance of the retaining wall panel, thereby effectively limiting the small rheological changes of the large volume of RAP filler material behind it.
[0015] The rigid control zone, which is set close to the retaining wall panel, naturally forms a vertical drainage channel. This channel can promptly clear seepage behind the wall and prevent local water accumulation. This not only effectively reduces the hydrostatic pressure on the panel, but also greatly avoids the adverse effects of water accumulation on the side RAP filler, such as asphalt softening and accelerated creep. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the cross-sectional structure of the RAP and aggregate partitioned composite reinforced retaining wall used to control creep in an embodiment of this application. Figure 2 This is a cross-sectional schematic diagram of the construction process of synchronous paving in zones and removal of temporary baffles in the construction method of this application embodiment; Figure 3 This is a logic diagram of the construction method in the embodiments of this application.
[0017] The components include: 1. Foundation; 2. Retaining wall panel; 3. Geogrid; 4. Rigid control zone; 5. Resource disposal zone; 6. Interface; 7. Movable baffle. Detailed Implementation
[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use.
[0019] like Figure 1As shown, this application discloses an embodiment of a RAP and aggregate partitioned composite reinforced retaining wall for controlling creep, which includes a foundation 1, a retaining wall panel 2, and a geogrid 3; the retaining wall panel 2 is fixedly installed on the foundation 1, and a filling area is provided between the retaining wall panel 2 and the foundation 1; wherein, the filling area includes an adjoining rigid control area 4 and a resource disposal area 5, the rigid control area 4 is located on the side closer to the retaining wall panel 2; the rigid control area 4 is provided with a first filler material with no creep characteristics, the resource disposal area 5 is provided with a second filler material, and a smooth interface 6 is formed at the junction of the first filler material and the second filler material; the geogrid 3 is placed inside the first filler material and the second filler material.
[0020] In this embodiment, the first filler is natural aggregate and the second filler is RAP filler. The rigid control zone 4 in the filling area is set with natural aggregate without creep characteristics, which effectively avoids the engineering hazard of serious creep deformation in the high stress zone near the retaining wall panel 2. The geogrid 3 is firmly embedded by the high friction angle of the rigid crushed stone zone, which greatly improves the horizontal displacement resistance of the retaining wall panel 2.
[0021] In some embodiments, the retaining wall panel 2 is perpendicular to the foundation 1 and parallel to the interface 6. The geogrid 3 and the interface 6 are perpendicular to each other in space. The horizontal width of the rigid control zone 4 is 0.5m to 1.0m. The natural aggregate is graded crushed stone or medium-coarse sand. The geogrid 3 is arranged in several layers, with the layers arranged vertically and the spacing between adjacent geogrids 3 is 0.12 to 0.18m. The resource disposal zone 5 has a larger volume than the rigid control zone 4 and is used to fill a larger amount of waste asphalt pavement material.
[0022] Based on extensive prior numerical simulations and experimental studies, this application clearly defines the vertical spacing of the geogrid 3 as 0.15m. Research confirms that a spacing greater than 0.25m results in insufficient creep restraint, while a spacing less than 0.12m causes an "over-reinforced soil" effect, leading to increased displacement and construction difficulties. The 0.15m spacing perfectly matches the height of the composite filler layer, achieving the optimal balance between material cost and creep resistance.
[0023] As attached Figure 3 As shown in the figure, this embodiment also discloses a construction method for a creep-controlled RAP and aggregate partitioned composite reinforced retaining wall, which includes the following steps: Based on the plane of foundation 1, fix retaining wall panel 2 on foundation 1, and form filling area of foundation 1 and retaining wall panel 2; A first layer of geogrid 3 is laid on the surface of foundation 1, and a movable baffle 7 is embedded on the surface of foundation 1 to divide the filling area into a rigid control zone 4 and a resource consumption zone 5. Fill the rigid control zone 4 with the first filler material and fill the resource disposal zone 5 with the second filler material; Remove the movable baffle 7 and mechanically compact the first and second fillers so that they mechanically interlock at the interface 6 to form a composite reinforced retaining wall.
[0024] As attached Figure 2 As shown in some embodiments, a construction method for a creep-controlled RAP and aggregate partitioned composite reinforced retaining wall is specifically designed as follows; The RAP material and natural aggregate were determined. Waste blocky asphalt material from road milling and resurfacing was fed into a crusher and crushed, then sieved through a 10mm standard sieve to ensure the maximum particle size did not exceed 11mm. Testing showed that the RAP material in this embodiment had a uniformity coefficient Cu=13.2 and a curvature coefficient Cc=1.27, indicating good gradation. Its natural moisture content was measured to be approximately 1%, and by adding water and stirring, the moisture content was strictly adjusted to 5.1% to ensure subsequent compaction. Coarse sand or continuously graded crushed stone from conventional road construction processes was used, requiring it to be free of impurities and possess good friction angle and water permeability.
[0025] Step 1: Level and compact the foundation 1, and securely install the bottom retaining wall panel 2; Step 2: Lay geogrid 3 flat on the foundation surface 1; Step 3: Perform zoned paving. Insert a 5mm thick steel movable baffle 7 vertically 0.5m from the retaining wall panel 2 facing the filling area. Pour continuous graded crushed stone into the 0.5m space between the retaining wall panel 2 and the movable baffle 7. Pave RAP filler in the space to the left of the movable baffle 7. Control the loose thickness of the material on both sides to be basically consistent. Step 4: After the paving of this layer is completed, slowly pull up the movable baffle 7 using machinery or manual labor to allow the continuous graded crushed stone and RAP filler to come into natural contact under the action of gravity. Step 5: Use a heavy roller to perform uniform compaction on the entire fill surface. The vibration of the roller causes the continuously graded crushed stone and RAP particles to interlock and embed at the interface 6, forming a mechanical bond. After compaction, testing and verification ensure that the thickness of this layer reaches the design value of 0.15m, and the compaction degree is greater than 95%. Step 6: Lay the second layer of geogrid 3 on the compacted surface, and repeat steps 2 to 5 above, filling layer by layer from bottom to top until the designed height of the wall of 6.0m is reached.
[0026] Performance Verification Explanation: Mechanical analysis reveals that traditional pure RAP retaining walls exhibit significant horizontal displacement and creep deformation under long-term loads. This is rooted in the shear stress near the panel, which activates the viscous flow of the asphalt. With the aforementioned structure and process, the direct stress-bearing medium of the retaining wall panel 2 becomes crushed stone with high stiffness and low long-term deformation characteristics. Simultaneously, due to the mesh effect of the geogrid 3, the crushed stone tightly embeds into the geogrid, creating a strong horizontal pull-out constraint on the rear RAP area. Under this macroscopic structural barrier, coupled with optimal spacing control of 0.15m, the long-term service settlement and horizontal displacement of this retaining wall will be controlled within millimeters and extremely low ranges, effectively improving the engineering challenges of using RAP as a high-fill retaining wall.
[0027] The rear resource disposal area 5 still uses a large volume of RAP material, preserving the environmentally friendly intention of waste recycling. During construction, movable baffles 7 are used to assist in the zonal paving and synchronous compaction process, which not only ensures clear boundaries but also guarantees the interlocking strength of the interface 6 between the two media. The process is simple and easy to promote in large-scale projects.
[0028] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0029] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.
Claims
1. A RAP-aggregate zoned composite reinforced retaining wall for controlling creep, characterized in that, include foundation; A retaining wall panel is fixedly installed on the foundation, and a filling area is provided between the retaining wall panel and the foundation; The filling area includes an adjoining rigid control area and a resource disposal area. The rigid control area is located on the side closer to the retaining wall panel. The rigid control area is provided with a first filler material with no creep characteristics, and the resource disposal area is provided with a second filler material. A smooth interface is formed at the junction of the first filler material and the second filler material. and geogrid, wherein the geogrid is placed inside the first filler and the second filler.
2. The RAP and aggregate zoned composite reinforced retaining wall for controlling creep as described in claim 1, characterized in that, The retaining wall panel is perpendicular to the foundation and parallel to the interface.
3. The RAP and aggregate zoned composite reinforced retaining wall for controlling creep as described in claim 1, characterized in that, The geogrid and the interface are perpendicular to each other in space.
4. The RAP and aggregate zoned composite reinforced retaining wall for controlling creep as described in claim 1, characterized in that, The geogrids are arranged vertically in multiple layers, with a spacing of 0.12 to 0.18 m between adjacent geogrids.
5. The RAP and aggregate zoned composite reinforced retaining wall for controlling creep according to claim 1, characterized in that, The volume of the resource consumption area is greater than the volume of the rigid control area.
6. A construction method for implementing the RAP and aggregate partitioned composite reinforced retaining wall for controlling creep as described in any one of claims 1 to 5, characterized in that, include According to the foundation plane, a retaining wall panel is fixed on the foundation, and the foundation and the retaining wall panel form a filling area; A geogrid is laid on the foundation surface, and a movable baffle is embedded on the foundation surface to divide the filling area into a rigid control area and a resource consumption area. The rigid control zone is filled with a first filler material, and the resource consumption zone is filled with a second filler material; Remove the movable baffle and mechanically crush the first filler and the second filler to form a mechanical interlock at the interface, thus forming a composite reinforced retaining wall.
7. The construction method according to claim 6, characterized in that, When the rigid control zone and the resource consumption zone are filled with materials, the thickness of the first filler and the second filler are equal.
8. The construction method according to claim 6, characterized in that, Mechanical compaction of the first filler and the second filler includes The compaction degree of both the first and second fillers is greater than 95% after mechanical compaction.
9. The construction method according to claim 6, characterized in that, It also includes the first filler configuration; The first filler configuration includes a first filler with a screening particle diameter of less than 11 mm; Add water to the first filler material after screening and stir to adjust the moisture content of the first filler material to 5.1%.
10. The construction method according to claim 6, characterized in that, The geogrid is laid in multiple layers, including A geogrid is then laid on the upper surface of the composite reinforced retaining wall. The first filler and the second filler are then refilled and compacted. The process of laying the geogrid and the first filler and the second filler and compacting are repeated to complete the laying of multiple layers of the geogrid.