Soft soil slope settlement and landslide treatment structure and construction method

Abstract

The present application belongs to the technical field of geotechnical engineering slope reinforcement, especially relates to a soft soil slope settlement and landslide treatment structure and construction method. The present application provides a reliable bearing layer for the anchoring assembly by setting the anchoring foundation deeply buried in the slope body, effectively overcomes the problem of insufficient anchoring force caused by low soft soil friction resistance, makes the material strength of the anchor rod fully play, uses the anchoring assembly connecting the anchoring foundation and the slope surface bearing structure to transfer the slope sliding force to the deep stable soil layer, realizes the effective transfer and diffusion of the load, reduces the stress concentration and mobilizes the deep soil resistance, simultaneously actively limits the slope surface deformation by the constraint assembly fixed with the bearing structure, and timely removes the accumulated water and reduces the pore water pressure through the drainage structure arranged on the bearing structure, finally through the synergistic working mechanism of deep anchoring, slope surface constraint and efficient drainage, significantly improves the overall stability, anti-settlement and anti-sliding capacity of the soft soil slope.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering slope reinforcement technology, and particularly relates to a structure and construction method for treating settlement and landslides on soft soil slopes. Background Technology

[0002] Soft soil slopes refer to natural or artificially constructed slopes composed of silt, silty soil, peat, organic soil, or other highly compressible, low-strength soils. These soils typically exhibit unfavorable engineering characteristics such as high water content, large void ratio, high compressibility, low shear strength, poor permeability, and significant rheological properties. Under the influence of their own weight, external loads (such as building loads and traffic vibrations), or changes in hydraulic conditions (such as rainfall infiltration and groundwater level fluctuations), soft soil slopes are prone to significant settlement deformation and lateral displacement, and may even experience overall slippage and instability, seriously threatening engineering safety.

[0003] In existing technologies, soft soil slope protection has certain limitations: when using anchor bolts (cables) for support, the anchoring force depends entirely on the mechanical properties of the soil surrounding the anchoring section. However, soft soil provides low frictional resistance, resulting in insufficient anchoring force and poor reliability of the anchor bolts, making it difficult to fully utilize the strength of the anchor bolt material itself. When using pile foundation support, since the stiffness of the pile is much greater than that of the soft soil around the pile, the stress at the top of the pile under load is significantly higher than the surface stress of the soil between the piles. The piles transfer the load to deeper soil layers, which also increases the load borne by the soil between the piles, easily causing stress concentration and uneven settlement.

[0004] Therefore, a structure for treating settlement and landslides on soft soil slopes and a corresponding construction method are proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a structure and construction method for treating settlement and landslides on soft soil slopes, in order to solve the above-mentioned problems.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A soft soil slope settlement and landslide control structure includes: an anchor foundation disposed within the slope body; an anchor component, one end of which is fixedly connected to the anchor foundation and the other end of which extends beyond the slope surface; a load-bearing structure fixedly connected to the end of the anchor component extending beyond the slope surface; a restraint component fixedly connected to the load-bearing structure, the restraint component being used to restrain the deformation of the slope surface; and a drainage structure disposed on the load-bearing structure.

[0008] In the soft soil slope settlement and landslide treatment structure of the present invention, the anchoring foundation includes: a multi-row pile structure, which is equally spaced along the direction away from the slope surface. The pile structure includes multiple piles, and the multiple piles in the same pile structure are arranged sequentially along the length of the slope. The piles in adjacent rows of pile structures are staggered. The piles are vertically embedded in the slope body, and the top of the piles extends out of the top of the slope body.

[0009] In the soft soil slope settlement and landslide treatment structure of the present invention, the anchoring component includes: a multi-row anchor structure, arranged sequentially from top to bottom along the slope surface, the anchor structure including multiple anchors, the multiple anchors in the same anchor structure being arranged sequentially along the length direction of the slope, and the anchors of adjacent rows of anchor structures being staggered; the multi-row pile structure and the multi-row anchor structure are arranged one-to-one, one end of the anchor is fixed to the pile body, and the other end extends out of the slope surface.

[0010] In the soft soil slope settlement and landslide treatment structure of the present invention, the bearing structure includes: a steel mesh, which is laid on the slope surface of the slope body, and one end of each of the multiple anchor rods extending out of the slope surface is fixedly connected to the steel mesh, and the fixing point of the anchor rod and the steel mesh forms an anchor point.

[0011] In the soft soil slope settlement and landslide treatment structure of the present invention, the restraint component includes: a concrete surface layer laid on the slope surface of the slope body, and the steel mesh set inside the concrete surface layer.

[0012] In the soft soil slope settlement and landslide treatment structure of the present invention, the drainage structure includes: multiple drainage components arranged sequentially from top to bottom along the slope surface of the slope, each drainage component including multiple drainage pipes, multiple drainage pipes in the same drainage component arranged sequentially along the length direction of the slope, the drainage pipes being buried in the concrete surface layer, the drainage pipes in adjacent rows of drainage components being staggered, one end of the drainage pipe extending into the slope surface of the slope, and the other end of the drainage pipe extending out of the concrete surface layer.

[0013] In the soft soil slope settlement and landslide treatment structure of the present invention, the pile body is made of silicate cement, fly ash, crushed stone, sand and water-reducing agent.

[0014] In the soft soil slope settlement and landslide control structure of the present invention, the anchor rod includes a glass fiber reinforced plastic anchor rod.

[0015] In the soft soil slope settlement and landslide treatment structure of the present invention, the angle between the anchor rod and the horizontal plane is 10°~30°.

[0016] A construction method for a soft soil slope settlement and landslide control structure is provided. The method comprises the following steps: constructing an anchor foundation at the top of the slope; drilling holes and constructing anchor components on the slope surface; fixing one end of the anchor component to the anchor foundation via grouting; and extending the other end of the anchor component through the slope surface. A load-bearing structure is then laid on the slope surface, and the load-bearing structure is fixed to the end of the anchor component extending through the slope surface. A restraint component is constructed on the load-bearing structure, and a drainage structure is pre-embedded during the construction of the restraint component. Construction is then complete.

[0017] Compared with the prior art, the present invention has the following advantages and technical effects:

[0018] In this invention, by setting anchor foundations deeply embedded in the slope body, a stable and reliable bearing layer is provided for the anchor components, effectively overcoming the problem of insufficient anchoring force caused by the low surface friction of soft soil. This allows the strength of the anchor (cable) material to be fully utilized, significantly improving the reliability and anchoring force of the support system. The anchor components firmly connect the anchor foundations to the bearing structure on the slope surface, transferring the slope sliding force to the deep stable soil layer through the bearing structure, achieving effective load transfer and diffusion. This not only reduces stress concentration in the piles or shallow soil but also helps to mobilize the resistance of deeper soil, improving the slope's stress state and overall stability. The constraint components fixedly connected to the bearing structure actively limit the lateral deformation and vertical settlement of the slope soil, promptly suppressing deformation development. Meanwhile, the drainage structure set on the bearing structure effectively removes water accumulation inside the slope, reducing pore water pressure and mitigating the adverse effects of hydraulic action on the soft soil properties. Thus, the long-term stability of the slope is synergistically improved from both drainage consolidation and deformation control perspectives. This invention organically combines deep anchoring, slope constraint, and efficient drainage to form a synergistic working mechanism, which significantly enhances the anti-settlement and anti-sliding capabilities of soft soil slopes. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 This is an axial view of the slope in this invention;

[0022] Figure 3 This is a schematic diagram of the arrangement of the piles in this invention;

[0023] Among them, 1. slope; 2. pile; 3. anchor rod; 4. steel mesh; 5. concrete surface layer; 6. anchor point; 7. drainage pipe; 3a. anchoring section. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Reference Figures 1 to 3 This invention discloses a soft soil slope settlement and landslide control structure, comprising: an anchor foundation, set inside the slope body 1; an anchor component, one end of which is fixedly connected to the anchor foundation and the other end of which extends out of the slope surface of the slope body 1; a load-bearing structure, fixedly connected to the end of the anchor component extending out of the slope surface of the slope body 1; a restraint component, fixedly connected to the load-bearing structure, the restraint component being used to restrain the deformation of the slope surface of the slope body 1; and a drainage structure, set on the load-bearing structure.

[0027] In this invention, by setting anchor foundations deeply embedded in the slope body, a stable and reliable bearing layer is provided for the anchor components, effectively overcoming the problem of insufficient anchoring force caused by the low surface friction of soft soil. This allows the strength of the anchor (cable) material to be fully utilized, significantly improving the reliability and anchoring force of the support system. The anchor components firmly connect the anchor foundations to the bearing structure on the slope surface, transferring the slope sliding force to the deep stable soil layer through the bearing structure, achieving effective load transfer and diffusion. This not only reduces stress concentration in the piles or shallow soil but also helps to mobilize the resistance of deeper soil, improving the slope's stress state and overall stability. The constraint components fixedly connected to the bearing structure actively limit the lateral deformation and vertical settlement of the slope soil, promptly suppressing deformation development. Meanwhile, the drainage structure set on the bearing structure effectively removes water accumulation inside the slope, reducing pore water pressure and mitigating the adverse effects of hydraulic action on the soft soil properties. Thus, the long-term stability of the slope is synergistically improved from both drainage consolidation and deformation control perspectives. This invention organically combines deep anchoring, slope constraint, and efficient drainage to form a synergistic working mechanism, which significantly enhances the anti-settlement and anti-sliding capabilities of soft soil slopes.

[0028] In one alternative scheme, the anchoring foundation includes: a multi-row pile structure, which is equally spaced along the direction away from the slope surface of the slope 1. The pile structure includes multiple piles 2. The multiple piles 2 in the same pile structure are arranged sequentially at intervals along the length direction of the slope 1. The piles 2 of adjacent rows of pile structures are staggered. The piles 2 are vertically embedded in the slope 1, and the top of the piles 2 extends out of the top of the slope 1.

[0029] In one alternative embodiment, the anchoring assembly includes: a multi-row anchor structure arranged sequentially from top to bottom along the slope surface of the slope 1, the anchor structure including multiple anchors 3, the multiple anchors 3 within the same anchor structure arranged sequentially along the length direction of the slope 1, and the anchors 3 of adjacent rows of anchor structures being staggered; a multi-row pile structure corresponding one-to-one with the multi-row anchor structure, one end of the anchor 3 being fixed to the pile body 2, and the other end extending out of the slope surface of the slope 1.

[0030] Reference Figure 1 Taking a three-row pile structure as an example, the anchoring section 3a of the uppermost anchor rod 3 is fixed to the pile structure that is furthest from the slope, the anchoring section 3a of the middle anchor rod 3 is fixed to the pile structure that is in the middle, and the anchoring section 3a of the lowermost anchor rod 3 is fixed to the pile structure that is closest to the slope.

[0031] As the number of piles increases or decreases, the anchor rod 3 and the pile body 2 are still connected in the same way.

[0032] In one alternative scheme, the load-bearing structure includes: a steel mesh 4, laid on the slope surface of the slope 1, and multiple anchor rods 3 extending out of the slope surface of the slope 1 and fixedly connected to the steel mesh 4 at one end, with the anchor rods 3 and the steel mesh 4 forming anchor points 6.

[0033] In one alternative embodiment, the restraint components include: a concrete surface layer 5 laid on the slope surface of the slope 1, and a steel mesh 4 disposed within the concrete surface layer 5.

[0034] In one alternative, the drainage structure includes: multiple drainage components arranged sequentially from top to bottom along the slope surface of the slope 1; each drainage component includes multiple drainage pipes 7; multiple drainage pipes 7 within the same drainage component are arranged sequentially along the length of the slope 1; the drainage pipes 7 are embedded in the concrete surface layer 5; the drainage pipes 7 in adjacent drainage components are staggered; one end of the drainage pipe 7 extends into the slope surface of the slope 1; and the other end of the drainage pipe 7 extends out of the concrete surface layer 5.

[0035] In one alternative, the material of pile 2 includes silicate cement, fly ash, crushed stone, sand, and water-reducing agent.

[0036] In one alternative, the anchor bolt 3 comprises a glass fiber reinforced plastic anchor bolt.

[0037] In one alternative scheme, the angle between the anchor rod 3 and the horizontal plane is 10° to 30°.

[0038] A construction method for a soft soil slope settlement and landslide control structure is disclosed. The method comprises the following steps: constructing an anchor foundation at the top of slope 1; drilling holes and constructing anchor components on the slope surface of slope 1; fixing one end of the anchor component to the anchor foundation by grouting; and having the other end of the anchor component protrude through the slope surface of slope 1. A load-bearing structure is laid on the slope surface of slope 1, and the load-bearing structure is fixed to the end of the anchor component protruding through the slope surface of slope 1. A restraint component is constructed on the load-bearing structure, and a drainage structure is pre-embedded during the construction of the restraint component. The construction is then completed.

[0039] The specific construction methods are as follows: S1. Construction preparation and surveying: Clean and level the slope 1, set up drainage ditches to reduce the impact of surface water. Use a total station to accurately locate the position according to the design drawings, clearly mark the center position of each pile 2 with wooden stakes or steel bars, and measure and record the original elevation.

[0040] Construction of S2 and Pile 2: A long spiral drilling rig will be used to drill to the designed depth of 20.0m. Hole collapse is strictly prohibited during drilling. After reaching the elevation, a cement-fly ash-aggregate mixture will be pumped through the central pipe of the drill rod. This mixture includes P·O42.5R ordinary Portland cement, Grade II fly ash, 5-25mm continuously graded crushed stone with a mud content of <1%, medium sand with a fineness modulus of 2.6, and a high-efficiency water-reducing agent at a dosage of 0.8% of the total cementitious materials. The water-cement ratio of the cement-fly ash-aggregate mixture is 0.50. Through test block experiments, the unconfined compressive strength of Pile 2 after 28 days of curing must be ≥20MPa. The pumping pressure must not be lower than 10MPa. The drill rod will be raised at a uniform speed during pumping, controlled at 1.5-2.0m / min, to ensure pile quality. A staggered driving method will be used, with an interval of more than 24 hours between the construction of adjacent Pile 2 sections. After pile construction, the piles were naturally cured for 28 days, and the integrity of the pile body was tested using low-strain testing.

[0041] S3. Slope Repair: Repair the slope surface of slope 1 to the designed slope surface. The slope surface flatness deviation should be controlled within ±20mm.

[0042] S4. Construction of Fiberglass Reinforced Plastic Anchor Bolts: On the prepared slope, accurately mark the positions of anchor bolt 3 holes, ensuring the anchor holes are located at the center of pile 2. Use a hydraulic anchor bolt drilling machine with a gold drill bit to drill the holes. The drilling diameter is 150mm. The drilling depth is the free section length of anchor bolt 3 plus the anchoring section length plus the exposed length. Fabricate the anchor bolt 3 on a leveled site. Cut the bolt to the designed length. Within the free section length, the anchor bolt 3 needs to be coated with grease and fitted with a corrugated pipe to form a free expansion section. A centering bracket (isolation frame) is installed every 1.5m along the anchoring section 3a to ensure the anchor bolt 3 is centered in the anchor hole. The grouting pipe (one-time atmospheric pressure grouting, preferably PVC pipe) should be securely tied to the anchor bolt 3, with the pipe end 50mm-100mm from the bottom of the anchor hole. Slowly and steadily insert the fabricated anchor bolt 3 into the hole, avoiding disturbance to the hole wall. Use bottom-return grouting for one-time atmospheric pressure grouting. The grout is a pure cement grout with a water-cement ratio of 0.45–0.50. The grout is injected into the bottom of the hole through the grouting pipe using a grouting pump. The grout fills the hole from the bottom upwards, expelling air, until grout overflows from the hole opening. Grouting pressure should not be less than 0.6 MPa. Anchor rods 3 are arranged in three rows vertically, with a horizontal spacing of 1.5 m and an angle of 15° with the horizontal plane. The length of the free expansion section of anchor rod 3 is calculated based on the slope length and the inclination angle of anchor rod 3. The length of anchoring section 3a is calculated based on the design pull-out force of anchor rod 3 and the bond strength provided by pile body 2. The bond strength provided by pile body 2 is determined through on-site pull-out tests and meets the minimum structural length requirements of the specifications. A dedicated glass fiber reinforced plastic anchor rod bonding type anchor is used, equipped with a 200mm × 200mm × 20mm steel pad. The surface of the steel pad is heavily corrosion-resistant. Anchoring section 3a must be entirely located within the pile body of pile body 2, which has been cured to the required strength.

[0043] S5. Laying the reinforcing mesh 4: Lay the prefabricated reinforcing mesh 4 tightly against the slope surface. The reinforcing mesh 4 should be firmly connected to each other and to the heads of the anchor rods 3, using binding or welding methods. For prestressed anchor rods, a continuous longitudinal wainscoting is usually installed at the anchor rod head. Two C18 channel steels can be placed back-to-back to evenly transfer the concentrated force of the anchor rod 3 to the surface layer. Pass the anchor rod 3 through the wainscoting and temporarily fix it with steel pads. The reinforcing mesh 4 uses HPB300 steel bars with a diameter of Φ8 and a mesh size of 200mm × 200mm. The overlap length between mesh panels should not be less than 300mm.

[0044] S6. Construction of Concrete Surface Layer 5: Wet spraying method will be used. Concrete prepared according to the design mix proportions, with an accelerator added, will be delivered to the spray nozzle using a concrete spraying machine and sprayed at high speed onto the slope under the action of compressed air. Spraying should be carried out from top to bottom, maintaining a distance of 0.8–1.2 m between the nozzle and the slope surface, and as perpendicular to the slope as possible. Spraying should be carried out in layers, with each layer applied after the previous layer has fully set. The thickness should be checked promptly after spraying to ensure it reaches the design value of 150 mm, and the surface should be smoothed. The design thickness of concrete surface layer 5 is 150 mm, the strength grade is C20, and the accelerator dosage is 3%–5% of the cement weight to meet the requirements of early strength and immediate support.

[0045] S7. Curing and Monitoring: Water curing shall begin 2 hours after the concrete surface layer has set, and the curing period shall not be less than 7 days. Throughout the entire excavation and support process of the foundation pit, the horizontal displacement, vertical settlement, and anchor stress at the top of the foundation pit shall be systematically monitored, and information-based construction shall be implemented to ensure safety.

[0046] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to 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 of this invention.

[0047] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A structure for controlling settlement and landslides on soft soil slopes, characterized in that, include: Anchor foundations are set within the slope (1); An anchoring assembly, one end of which is fixed to the anchoring foundation, and the other end of which extends out of the slope surface of the slope (1); The load-bearing structure is fixedly connected to one end of the anchoring component that extends out of the slope surface of the slope (1); A constraint component is fixedly connected to the bearing structure, and the constraint component is used to constrain the deformation of the slope surface of the slope (1); A drainage structure is provided on the load-bearing structure; The anchoring foundation includes: A multi-row pile structure is set at equal intervals along the direction away from the slope surface (1). The pile structure includes multiple piles (2). The multiple piles (2) in the same pile structure are arranged sequentially at intervals along the length direction of the slope (1). The piles (2) of adjacent rows of pile structures are staggered. The pile (2) is vertically embedded in the slope (1), and the top of the pile (2) extends out of the top of the slope (1); The anchoring assembly includes: The anchor structure is arranged in a series of rows from top to bottom along the slope surface of the slope (1). The anchor structure includes multiple anchors (3). The multiple anchors (3) in the same anchor structure are arranged in a series of rows along the length of the slope (1). The anchors (3) in two adjacent rows of the anchor structure are staggered. The pile structure in multiple rows is set up one-to-one with the anchor structure in multiple rows. One end of the anchor (3) is fixed to the pile body (2), and the other end extends out of the slope surface of the slope body (1). The load-bearing structure includes: A steel mesh (4) is laid on the slope surface of the slope (1). One end of each of the anchor rods (3) that protrudes from the slope surface of the slope (1) is fixedly connected to the steel mesh (4). An anchor point (6) is formed at the fixed point of the anchor rod (3) and the steel mesh (4).

2. The soft soil slope settlement and landslide control structure according to claim 1, characterized in that, The constraint component includes: A concrete surface layer (5) is laid on the slope surface of the slope (1), and the steel mesh (4) is set inside the concrete surface layer (5).

3. The soft soil slope settlement and landslide control structure according to claim 2, characterized in that, The drainage structure includes: Multiple drainage components are arranged sequentially from top to bottom along the slope surface of the slope (1). Each drainage component includes multiple drainage pipes (7). Multiple drainage pipes (7) in the same drainage component are arranged sequentially along the length direction of the slope (1). The drainage pipes (7) are buried in the concrete surface layer (5). The drainage pipes (7) in two adjacent rows of drainage components are staggered. One end of the drainage pipe (7) extends into the slope surface of the slope (1), and the other end of the drainage pipe (7) extends out of the concrete surface layer (5).

4. The soft soil slope settlement and landslide control structure according to claim 1, characterized in that, The materials of the pile body (2) include silicate cement, fly ash, crushed stone, sand and water-reducing agent.

5. The soft soil slope settlement and landslide control structure according to claim 1, characterized in that, The anchor (3) includes a glass fiber reinforced plastic anchor.

6. The soft soil slope settlement and landslide control structure according to claim 1, characterized in that, The angle between the anchor rod (3) and the horizontal plane is 10°~30°.

7. A construction method for a soft soil slope settlement and landslide control structure, used for constructing the soft soil slope settlement and landslide control structure according to any one of claims 1-6, characterized in that, The steps are as follows: An anchor foundation is constructed at the top of the slope (1). Holes are drilled on the slope surface of the slope (1) and anchor components are constructed. One end of the anchor component is fixed to the anchor foundation by grouting. The other end of the anchor component extends out of the slope surface of the slope (1). A bearing structure is laid on the slope surface of the slope (1), and the bearing structure is fixed to the end of the anchor component extending out of the slope surface of the slope (1). A restraint component is constructed on the bearing structure, and a drainage structure is pre-embedded when constructing the restraint component. The construction is completed.

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