A method for preventing settlement of a basement edge ground surface pavement
By using layered backfilling and compaction and laying geogrids, the problem of road surface settlement around the basement was solved, the stability and bearing capacity of the roadbed were enhanced, and the long-term use of the road was ensured.
Patent Information
- Application Number
- CN202610284424.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-10
- Publication Date
- 2026-06-09
AI Technical Summary
Uneven settlement of the road surface around the basement caused by the basement construction has resulted in cracks and structural damage to the road surface, affecting normal use.
A layered backfilling and compaction method was adopted, and a 20cm thick C30 reinforced concrete anti-sinking slab was laid. A 2m wide bidirectional warp-knitted polyester geogrid was laid at its edge to ensure that the load was transferred to the original soil layer and to prevent reflective cracking at the joint.
It effectively solved the problem of uneven settlement of the road surface around the basement, enhanced the strength and stability of the roadbed, reduced the impact of vehicle load on the basement exterior wall, and extended the service life of the road.
Smart Images
Figure CN122169411A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of road surface settlement prevention technology, specifically a method for preventing settlement of the surface pavement at the edge of a basement. Background Technology
[0002] Currently, most residential communities and public buildings are equipped with underground parking garages or underground civil defense spaces. Therefore, some surface roads in these communities are located above the basements, some on the original soil layer, or even pass through the basements. These underground parking garages and civil defense spaces are primarily reinforced concrete structures with raft or pile-raft foundations, resulting in relatively small settlement. However, due to the excavation and construction of the basements, the surrounding area is filled with soil, leading to relatively large secondary consolidation settlement after construction. Consequently, the road surface around the basements frequently subsides, causing cracks, rainwater infiltration, and ultimately damaging the road structure, even affecting the normal use of the basements. Therefore, a method for preventing settlement of the surface road surface at the basement edge is needed to address these shortcomings. Summary of the Invention
[0003] The purpose of this invention is to provide a method for preventing settlement of the surface pavement at the edge of a basement, so as to solve the problems mentioned in the background art.
[0004] To achieve the above objectives, the present invention provides the following technical solution: A method for preventing settlement of the surface pavement at the edge of a basement, comprising the following steps: Step 1: First, backfill and compact the excavated surface of the basement in layers until the compaction degree meets the design requirements. Step 2: After backfilling the excavated surface to the appropriate position of the basement top, construct a 20cm thick C30 reinforced concrete anti-settlement slab; Step 3: After the anti-settlement slab is poured and cured, lay a 2m wide geogrid symmetrically along its edges to prevent reflective cracks from appearing on the road surface at the joints.
[0005] Preferably, the backfill soil is backfilled in layers with compaction to ensure that the backfill soil is fully compacted and to reduce post-construction settlement. The thickness of each layer should be controlled between 15 and 20 cm. If mechanical compaction cannot be used due to the excavation range limitation, small tools such as hand rammers should be used to compact the soil to ensure that the compaction degree meets the requirements of the design documents. The top elevation of the backfill soil 8 should be determined comprehensively based on the road surface design elevation, the basement roof elevation, the road structure layer design thickness, the anti-settlement slab thickness, and the crushed stone cushion layer thickness.
[0006] Preferably, the reinforced concrete anti-settlement slab is made of 20cm thick C30 reinforced concrete and must span the basement excavation and backfill area. One end is placed on the edge of the basement roof slab with a support width of 50cm, and the height difference between the support slab and the anti-settlement slab is adjusted using a 49mm brick wall. The other end is placed on the undisturbed original soil layer with a support width of 50cm. To ensure that the load is fully transferred to the original soil layer, the support position should be placed further back, not less than 50cm from the excavation slope line, and a 10cm C20 concrete cushion layer is provided on the top surface of the original soil layer. The height difference between the original soil layer and the anti-settlement slab is also adjusted using a 49mm brick wall. A single layer of bidirectional C12@20cm steel mesh is placed at the bottom of the anti-settlement slab, and a 10cm thick crushed stone cushion layer is placed under the anti-settlement slab.
[0007] Preferably, the geogrid is a biaxial warp-knitted polyester geogrid GGR / PET / BK100-100, with a nominal longitudinal and transverse tensile strength of 100kN / m, a unit area mass ≥330g / m2, a tensile strength of 18kN / m at 2% elongation in both longitudinal and transverse directions, a tensile strength ≥36kN / m at 5% elongation in both longitudinal and transverse directions, a nominal elongation in both longitudinal and transverse directions ≤13%, and a UV resistance retention rate ≥80%.
[0008] Preferably, the geogrid is 2m wide. After the anti-settlement slab is poured and cured, it is laid symmetrically across the seams at its edge, and both ends are fixed to the ground with U-shaped nails at a spacing of 1.0m.
[0009] Compared with existing technologies, this invention has the following advantages: This method for preventing settlement of the ground surface at the edge of the basement successfully solves the problem of uneven settlement of the road surface around the basement. In addition, this method can reduce the impact of vehicle impact loads on the basement exterior walls, ensure the strength, rigidity, and stability of the roadbed, improve the bearing capacity of the roadbed and pavement, and fully guarantee the design service life of the road. Attached Figure Description
[0010] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the overall cross-sectional structure of the present invention.
[0011] In the diagram: 1. Anti-settlement slab; 2. Crushed stone cushion layer; 3. 49 brick wall; 4. Concrete cushion layer; 5. Geogrid; 6. Basement roof slab; 7. Excavation slope line; 8. Backfill soil; 9. Original soil; 10. Road surface structure. Detailed Implementation
[0012] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. It should also be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings. In the embodiments of the present invention, the different types of cross-sectional lines are not labeled according to national standards, nor do they specify material requirements for the components; they are used to distinguish the cross-sectional views of the components.
[0013] Please see Figure 1 A method for preventing settlement of the surface pavement at the edge of a basement, comprising the following steps: Step 1: First, backfill and compact the excavated surface of the basement in layers until the compaction degree meets the design requirements. Step 2: After backfilling the excavated surface to the appropriate position of the basement top, construct a 20cm thick C30 reinforced concrete anti-settlement slab; Step 3: After the anti-settlement slab is poured and cured, lay a 2m wide geogrid symmetrically along its edges to prevent reflective cracks from appearing on the road surface at the joints.
[0014] Among them, backfill soil 8 is backfilled in layers with compaction to ensure that the backfill soil is fully compacted and to reduce post-construction settlement. The thickness of each layer should be controlled between 15 and 20 cm. If mechanical compaction cannot be used due to the excavation range, small tools such as hand rammers must be used to compact the soil to ensure that the compaction degree meets the requirements of the design documents. The top elevation of backfill soil 8 must be determined comprehensively based on the road surface design elevation, the basement roof slab 6 elevation, the design thickness of the road structure layer 10, the thickness of the anti-settlement slab 1, and the thickness of the crushed stone cushion layer 2.
[0015] The reinforced concrete anti-settlement slab 1 is made of 20cm thick C30 reinforced concrete and must span the basement excavation and backfill area. One end rests on the edge of the basement roof slab 6 with a resting width of 50cm. The height difference between the anti-settlement slab 1 and the support slab is adjusted by a 49 brick wall. The other end rests on the undisturbed original soil layer 9 with a resting width of 50cm. To ensure that the load is fully transferred to the original soil layer 9, the support position should be placed further back, not less than 50cm from the excavation slope line 7. A 10cm C20 concrete cushion layer is set on the top surface of the original soil layer 9. The height difference between the original soil layer 9 and the support slab 1 is also adjusted by a 49 brick wall. A single layer of bidirectional C12@20cm steel mesh is installed at the bottom inside the anti-settlement slab 1. A 10cm thick crushed stone cushion layer 4 is set under the anti-settlement slab 1.
[0016] Among them, geogrid 5 adopts biaxial warp-knitted polyester geogrid GGR / PET / BK100-100, with a nominal tensile strength of 100kN / m in both longitudinal and transverse directions, a unit area mass ≥330g / m2, a tensile strength of 18kN / m at 2% elongation in both longitudinal and transverse directions, a tensile strength ≥36kN / m at 5% elongation in both longitudinal and transverse directions, a nominal elongation of ≤13% in both longitudinal and transverse directions, and a UV resistance retention rate ≥80%.
[0017] Among them, the geogrid 5 is 2m wide. After the anti-settlement board 1 is poured and cured, it is symmetrically laid across the joint at its edge, and the two ends are fixed to the ground with U-shaped nails at a spacing of 1.0m.
[0018] It should be noted that when implementing the anti-settlement method for the ground surface at the edge of the basement, the excavated surface of the basement should first be backfilled and compacted in layers. The thickness of each layer should be controlled between 15 and 20 cm. If mechanical compaction cannot be used due to the excavation range, small tools such as hand rammers can be used to compact the soil to ensure that the compaction degree meets the requirements of the design documents. The top elevation of the backfill soil must be determined comprehensively based on the design elevation of the road surface, the elevation of the basement roof slab, the design thickness of the road structure layer, the thickness of the anti-settlement slab, and the thickness of the crushed stone cushion layer.
[0019] After the backfilling is completed, a 20cm thick C30 reinforced concrete anti-settlement slab is constructed. The slab is made of 20cm thick C30 reinforced concrete and spans the basement excavation and backfill area. One end rests on the edge of the basement roof slab with a 50cm width, and the height difference between the slab and the anti-settlement slab is adjusted using a 49mm brick wall. The other end rests on the undisturbed original soil layer with a 50cm width. To ensure sufficient load transfer to the original soil layer, the resting position should be positioned further back, at least 50cm from the excavation slope line. A 10cm C20 concrete cushion layer is placed on the top surface of the original soil layer, and the height difference between the original soil layer and the anti-settlement slab is also adjusted using a 49mm brick wall. A single-layer, two-way C12@20cm steel mesh is placed at the bottom of the anti-settlement slab, and a 10cm thick crushed stone cushion layer is placed beneath it.
[0020] After the anti-settlement slab is poured and cured, a 2m wide geogrid is symmetrically laid across the joints at its edges. The geogrid is a bidirectional warp-knitted polyester geogrid GGR / PET / BK100-100 with a nominal tensile strength of 100kN / m in both longitudinal and transverse directions, a unit area mass ≥330g / m2, a tensile strength of 18kN / m at 2% elongation in both longitudinal and transverse directions, a tensile strength ≥36kN / m at 5% elongation in both longitudinal and transverse directions, a nominal elongation of ≤13% in both longitudinal and transverse directions, and a UV resistance retention rate ≥80%. Both ends are fixed to the ground with U-shaped nails at 1.0m intervals.
[0021] The contents not described in detail in this specification are existing technologies known to those skilled in the art.
[0022] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.
Claims
1. A method for preventing settlement of the surface pavement at the edge of a basement, comprising the following steps: Step 1: First, backfill and compact the excavated surface of the basement in layers until the compaction degree meets the design requirements. Step 2: After backfilling the excavated surface to the appropriate position of the basement top, construct a 20cm thick C30 reinforced concrete anti-settlement slab; Step 3: After the anti-settlement slab is poured and cured, lay a 2m wide geogrid symmetrically along its edges to prevent reflective cracks from appearing on the road surface at the joints.
2. The method for preventing settlement of the ground surface at the edge of a basement according to claim 1, characterized in that: The backfill soil (8) is backfilled in layers to ensure that the backfill soil is fully compacted and to reduce post-construction settlement. The thickness of each layer should be controlled between 15 and 20 cm. If mechanical compaction is not possible due to the excavation range, small tools such as hand rammers should be used to compact the soil to ensure that the compaction degree meets the requirements of the design documents. The top elevation of the backfill soil (8) should be determined comprehensively based on the road surface design elevation, the basement roof slab (6) elevation, the road structure layer (10) design thickness, the anti-settlement slab (1) thickness, and the crushed stone cushion layer (2) thickness.
3. The method for preventing settlement of the ground surface at the edge of a basement according to claim 1, characterized in that: The reinforced concrete anti-sinking slab (1) is made of 20cm thick C30 reinforced concrete and must cross the basement excavation and backfill area. One end is placed on the edge of the basement top slab (6) with a placement width of 50cm. The height difference between the anti-sinking slab (1) and the slab is adjusted by a 49 brick wall. The other end is placed on the undisturbed original soil layer (9) with a placement width of 50cm. In order to ensure that the load is fully transferred to the original soil layer (9), the placement position should be placed later, not less than 50cm from the excavation slope line (7). A 10cm C20 concrete cushion layer is set on the top surface of the original soil layer (9). The height difference between the original soil layer (9) and the slab (1) is also adjusted by a 49 brick wall. A single layer of bidirectional C12@20cm steel mesh is placed at the bottom inside the anti-sinking slab (1). A 10cm thick crushed stone cushion layer (4) is set under the anti-sinking slab (1).
4. The method for preventing settlement of the ground surface at the edge of a basement according to claim 1, characterized in that: The geogrid (5) is a biaxial warp-knitted polyester geogrid GGR / PET / BK100-100, with a nominal longitudinal and transverse tensile strength of 100kN / m, a unit area mass ≥330g / m2, a tensile strength of 18kN / m at 2% elongation in both longitudinal and transverse directions, a tensile strength ≥36kN / m at 5% elongation in both longitudinal and transverse directions, a nominal elongation in both longitudinal and transverse directions ≤13%, and a UV resistance retention rate ≥80%.
5. A method for preventing settlement of the ground surface at the edge of a basement according to claim 1, characterized in that: The geogrid (5) is 2m wide. After the anti-settlement board (1) is poured and cured, it is laid symmetrically across the seam at its edge joints. Both ends are fixed to the ground with U-shaped nails at a spacing of 1.0m.