Cantilevered rigid-flexible anti-seepage structure

Abstract

The utility model provides a cantilever rigid-flexible anti -infiltration structure, including flexible anti -infiltration wall, by plastic concrete constitutes, vertical bury in geological soil layer, rigid anti -infiltration wall coaxial is arranged on the top of flexible anti -infiltration wall, and the link of both is equipped with wedge groove structure, forms integral type rigid-flexible anti -infiltration wall structure, stake cap is connected in the rigid anti -infiltration wall top, its upper surface is flush with ground, is used for connecting the rigid anti -infiltration wall into a whole, and the cantilever side of rigid anti -infiltration wall is equipped with slope protection and foot protection. Solve the problem that traditional anti -infiltration wall and support pile separate structure design cost is high, and single strip anti -infiltration wall weak problem of shear strength.

Description

Technical Field

[0001] This utility model relates to the field of dam and water conservancy engineering technology, and in particular to a cantilevered rigid-flexible seepage prevention structure. Background Technology

[0002] In the expansion project of the ship lock at the water conservancy hub, the construction of the upstream approach channel slope requires the use of shoreline beach resources. According to the mandatory requirements of the dike engineering specifications, the no-toe protection zone on the water-facing side of important dikes must maintain a complete protection range of no less than 50m. The approach channel slope structure must strictly avoid this dike protection range, preventing any form of encroachment. To meet the functional requirements of the waterway, a 1:3 comprehensive stabilizing slope gradient is adopted, with a single-stage ramp structure. The ramp width is standardized at 3m to meet maintenance and passage requirements. Geotechnical calculations show that in some sections, due to abrupt changes in beach topography and existing structures, conventional slope design would exceed the dike protection boundary. To resolve the spatial constraints and simultaneously ensure the integrity of the dike's seepage prevention system, a new type of slope seepage prevention structure with high space utilization and complete structural functions is urgently needed. Utility Model Content

[0003] The main purpose of this utility model is to provide a cantilevered rigid-flexible seepage prevention structure to solve the problems of high cost and weak shear strength of traditional seepage prevention wall and support pile separate structural design.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a cantilevered rigid-flexible seepage prevention structure, including a flexible seepage prevention wall made of plastic concrete, which is vertically buried in the geological soil layer, and a rigid seepage prevention wall coaxially arranged above the flexible seepage prevention wall, and a wedge groove structure is provided at the joint between the two to form an integrated rigid-flexible seepage prevention wall structure. A pile cap is connected to the top of the rigid seepage prevention wall, and its upper surface is flush with the ground to connect the rigid seepage prevention wall into a whole. The cantilever side of the rigid seepage prevention wall is provided with slope protection and toe protection.

[0005] In the preferred embodiment, the top of the flexible impermeable wall is provided with multi-level stepped protrusions; The bottom of the rigid anti-seepage wall is equipped with a matching multi-level stepped groove; Multi-level stepped protrusions are embedded in multi-level stepped grooves, forming a coaxial interlocking connection structure between the rigid and flexible anti-seepage walls.

[0006] In the preferred embodiment, the number of steps in the multi-level stepped protrusions at the top of the flexible seepage barrier is 2-3.

[0007] In the preferred embodiment, the height difference between adjacent steps is configured to be 1 / 3 to 1 / 2 of the smaller thickness between the rigid and flexible cutoff walls.

[0008] In the preferred embodiment, the sidewalls of each step are provided with an outward slope, and the angle between the inclination angle and the vertical axis of the flexible impermeable wall is 5-8°.

[0009] In the preferred embodiment, the joint between the multi-level stepped protrusions at the top of the flexible cutoff wall and the multi-level stepped grooves at the bottom of the rigid cutoff wall is filled with expansive mortar.

[0010] In the preferred embodiment, the end of the slope protection and toe protection is anchored to the upper cantilever side of the rigid anti-seepage wall by prestressed tie rods; Alternatively, the ends of the slope protection and toe protection can be anchored to the cantilever side of the pile cap using prestressed tie rods.

[0011] In the preferred embodiment, the anchoring height between the slope protection toe and the rigid anti-seepage wall extends to the pile cap, and a waterproof facing is also provided on the cantilever side.

[0012] In the preferred embodiment, the prestressing direction of the prestressed tie rod is configured such that the prestressed steel bar bulges outward and bends upward towards the cantilever side.

[0013] In the preferred embodiment, the slope protection includes a riprap toe protection embedded in the geological soil layer on the cantilever side and a slope protection section covering the slope.

[0014] This invention provides a cantilevered rigid-flexible seepage-proof structure. Through the coaxial interlocking design of the rigid and flexible seepage-proof walls, the overall seepage-proof performance and structural stability are significantly improved. The flexible seepage-proof wall uses plastic concrete, whose low modulus of elasticity gives the wall excellent deformation adaptability, effectively absorbing the stress generated by uneven foundation settlement and preventing cracking. Simultaneously, the permeability coefficient of plastic concrete is much lower than that of ordinary concrete. Combined with the water-swelling property of clay particles, it can automatically fill tiny cracks, ensuring long-term seepage-proof sealing. The rigid seepage-proof wall provides high-strength support, resisting soil pressure and shear force. The two are tightly connected through a stepped tenon-and-groove structure, forming a rigid-flexible complementary integrated system.

[0015] The stepped tenon and groove structure decomposes shear force through inclined planes, reduces stress concentration at the connection interface, extends the seepage path, and lowers the risk of leakage. The height difference between adjacent steps is 1 / 3 to 1 / 2 of the thickness of the smaller wall, and the sidewalls are designed with an outward slope of 5-8° to further optimize stress distribution and allow for construction errors. The expansive mortar filling the connection gaps actively compacts the gaps, compensates for shrinkage, and enhances the interface sealing. The slope protection and toe protection are anchored to the rigid wall or the cantilever side of the pile cap by prestressed tie rods. The prestressing direction is designed to be convex outward and upward, forming reverse compressive stress at the turning point to counteract horizontal tensile and shear forces, preventing the slope protection and toe protection from sliding or cracking.

[0016] In summary, this structure replaces the traditional separate support piles and seepage barriers with an integrated design, saving materials and costs, while taking into account impermeability, shear resistance and foundation adaptability. It is especially suitable for slopes in water conservancy projects with limited space, and has significant economic benefits and engineering reliability. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a cross-sectional view of the seepage barrier structure when the slope protection and toe protection of this utility model are anchored to the rigid seepage barrier; Figure 2 This is a cross-sectional view of the anti-seepage wall structure when the slope protection and toe protection and pile cap are anchored in this utility model; Figure 3 This is a schematic diagram of the longitudinal section of the cantilevered rigid-flexible seepage-proof wall structure of this utility model; Figure 4 This is a partial structural diagram of the junction between the rigid and flexible seepage barriers of this utility model; Figure 5 This is a partial structural diagram of the connection between the slope protection and the rigid anti-seepage wall or pile cap of this utility model.

[0018] In the diagram: 1. Rigid anti-seepage wall; 101. Multi-stage stepped trench; 2. Flexible anti-seepage wall; 201. Multi-stage stepped protrusion; 3. Pile cap; 4. Slope protection and toe protection; 401. Rockfill toe protection; 402. Slope protection section; 5. Geological soil layer; 6. Prestressed tie rod; 7. Waterproof facing; 8. Expansive mortar. Detailed Implementation

[0019] Example 1 like Figure 1-5 As shown, a cantilevered rigid-flexible seepage prevention structure includes a flexible seepage prevention wall 2, which is made of plastic concrete and is vertically buried in the geological soil layer 5. A rigid seepage prevention wall 1 is coaxially arranged above the flexible seepage prevention wall 2, and a wedge groove structure is provided at the joint between the two to form an integrated rigid-flexible seepage prevention wall structure. A pile cap 3 is connected to the top of the rigid seepage prevention wall 1, and its upper surface is flush with the ground. It is used to connect the rigid seepage prevention wall 1 into a whole. A slope protection and toe protection 4 are provided on the cantilever side of the rigid seepage prevention wall 1.

[0020] This application employs a rigid-flexible cutoff wall structure to ensure the dike's impermeability. A diaphragm wall is installed at the cantilever end of the dike to enhance shear resistance. The lower section of the coaxial section uses a plastic concrete cutoff wall, which has good deformation adaptability and can resist uneven foundation settlement, ensuring seepage prevention and sealing. The upper rigid section uses a reinforced concrete continuous wall to provide high-strength support and resist soil pressure and shear force. Through the combination of rigidity and flexibility, both seepage prevention performance and structural stability are achieved, significantly reducing project costs, saving materials, ensuring safety and reliability, and demonstrating good economic benefits. This rigid-flexible cutoff wall replaces traditional support piles, eliminating the need for a separate support structure; the rigid-flexible cutoff wall directly undertakes the support function, reducing costs.

[0021] Plastic concrete achieves a dense microstructure through optimized mix design, and its permeability coefficient is typically controlled within a certain range. ~ With a flow rate on the order of cm / s, far lower than that of ordinary concrete, it can effectively block water seepage. When subjected to water pressure, the clay particles in the material expand when they come into contact with water, which can automatically fill the tiny cracks and improve the long-term seepage prevention stability.

[0022] Although plastic concrete becomes a solid after curing, its flexibility is mainly reflected in its material mechanical properties and structural adaptability. The elastic modulus of ordinary concrete is typically 2.5 × ~3.5× The elastic modulus of plastic concrete is 500-2000 MPa, only 1 / 10 to 1 / 20 that of ordinary concrete. This low elastic modulus gives plastic concrete a rubber-like deformation capacity; when uneven settlement occurs in the foundation, the wall can absorb stress through its own deformation, preventing cracking. The ultimate tensile strain of plastic concrete can reach 0.1-0.3%, while that of ordinary concrete is only 0.01-0.02%, allowing it to withstand greater tensile deformation without breaking.

[0023] Connecting with the rigid section, the flexible deformation of the lower plastic concrete buffers the foundation displacement, protecting the upper rigid wall from shear failure and ensuring overall seepage prevention continuity. The cantilever side slope protection toe restrains soil displacement, further reducing the deformation pressure on the plastic concrete wall.

[0024] In the preferred embodiment, the top of the flexible impermeable wall 2 is provided with multi-level stepped protrusions 201; The bottom end of the rigid anti-seepage wall 1 is provided with a matching multi-level stepped groove 101; The multi-level stepped protrusions 201 are embedded in the multi-level stepped grooves 101, and the rigid anti-seepage wall 1 and the flexible anti-seepage wall 2 form a coaxial interlocking connection structure.

[0025] In the preferred embodiment, the number of steps in the multi-level stepped protrusions 201 at the top of the flexible seepage barrier 2 is 2-3.

[0026] In the preferred embodiment, the height difference between adjacent steps is configured to be 1 / 3 to 1 / 2 of the smaller thickness of the rigid cutoff wall 1 and the flexible cutoff wall 2.

[0027] In the preferred embodiment, the sidewalls of each step are provided with an outward slope, and the angle between the inclination angle and the vertical axis of the flexible impermeable wall 2 is 5-8°.

[0028] Because the rigid cutoff wall 1 and the flexible cutoff wall 2 are made of different materials and their construction was not synchronized, the connection interface is unstable and has seepage gaps. Traditional solutions often use waterstops, but these waterstops are prone to aging and falling off, affecting their performance.

[0029] This embodiment preferably uses a three-tiered mortise and tenon structure. The shear force at the mortise and tenon joint is reduced by the decomposition of the inclined plane, which reduces stress concentration and cracking. The tiered structure allows for gap construction errors, reducing construction difficulty. At the same time, the tiered structure extends the seepage path and reduces the risk of seepage.

[0030] In the preferred embodiment, an expansive mortar 8 is provided at the connection gap between the multi-level stepped protrusion 201 at the top of the flexible seepage barrier wall 2 and the multi-level stepped groove 101 at the bottom of the rigid seepage barrier wall 1.

[0031] In the preferred embodiment, the end of the slope protection and toe protection 4 is anchored to the upper cantilever side of the rigid anti-seepage wall 1 by prestressed tie rod 6; Alternatively, the end of the slope protection toe 4 is cantilevered and anchored to the pile cap 3 via a prestressed tie rod 6.

[0032] Since the connection between the slope protection toe 4 and the rigid anti-seepage wall 1 or pile cap 3 is located on one side, and the cantilevered main body of the slope protection toe 4 is not equipped with other support and anchoring structures, the connection point of the slope protection toe 4 needs to be equipped with a prestressed structure to resist the overturning force caused by the slope protection toe 4 itself and the rigid anti-seepage wall 1 or pile cap 3 after being subjected to external forces.

[0033] In the preferred embodiment, the anchoring height between the slope protection and toe protection 4 and the rigid anti-seepage wall 1 reaches the pile cap 3, and a waterproof facing 7 is also provided on the cantilever side.

[0034] During construction, based on the design of the slope protection toe 4 and the stress and water level on the cantilever side, it is determined whether the slope protection toe 4 is anchored to the rigid cutoff wall 1 or the pile cap 3. The end of the slope protection toe 4 and the pile cap 3 are easier to construct, and the anchoring to the upper part of the rigid cutoff wall 1 has better tensile performance. However, the height of the cantilever side of the rigid cutoff wall 1 not covered by the slope protection toe 4 needs to be equipped with a waterproof facing 7 to accommodate higher water levels.

[0035] In the preferred embodiment, the prestressing direction of the prestressed tie rod 6 is configured such that the prestressed steel bar bulges outward and bends upward towards the cantilever side.

[0036] In the preferred embodiment, the slope protection 4 includes a riprap toe protection 401 embedded in the geological soil layer 5 on the cantilever side and a slope protection section 402 covering the slope.

[0037] During construction, a trench is first drilled into the geological soil layer 5, and concrete is poured to construct the flexible seepage barrier wall 2. After the concrete of the flexible seepage barrier wall 2 has initially set, the trench is enlarged at the top of the geological soil layer 5. The scum on the top of the concrete of the flexible seepage barrier wall 2 is cleaned, and then the steel cage of the rigid seepage barrier wall 1 is installed and concrete is poured. After final setting, the pile head of the rigid seepage barrier wall 1 is removed, the steel reinforcement of the pile cap 3 is tied, the formwork is installed, and concrete is poured. The soil on the cantilever side of the rigid seepage barrier wall 1 is excavated, and the slope protection and toe protection 4 are constructed to form a rigid-flexible seepage barrier wall structure together with the rigid seepage barrier wall 1, the flexible seepage barrier wall 2, and the pile cap 3.

[0038] The construction method for the connection between the rigid cutoff wall 1 and the flexible cutoff wall 2 is as follows: During the initial setting period of the concrete of the flexible cutoff wall 2, a steel formwork with a multi-level stepped protrusion 201 is pressed into its top. At this stage, the concrete is in a plastic solid state and can withstand the pressure of the formwork without damaging the structure. When the steel formwork is pushed in, it undergoes elastic deformation rather than cracking. Then, the side formwork of the rigid cutoff wall 1 is temporarily fixedly connected to the steel formwork to form a closed pouring cavity. The steel formwork serves as the top formwork of the flexible cutoff wall 2 after its initial setting and as its bottom formwork when pouring the concrete of the rigid cutoff wall 1. The weight of the rigid concrete further presses the steel formwork against the flexible cutoff wall 2 to assist in the formation of its top multi-level stepped protrusion 201.

[0039] Before the rigid cutoff wall 1 reaches its final set, remove the temporary anchoring between the steel formwork and the side formwork of the rigid cutoff wall 1, and pull the steel formwork out from the junction of the rigid cutoff wall 1 and the flexible cutoff wall 2 in sections from the side. Since the rigid cutoff wall 1 exerts a large pressure on the steel formwork at this time, hydraulic vibration can be used to demold the steel formwork.

[0040] After the steel formwork is removed, expansive mortar 8 is immediately pressure-injected into the stepped gap at the junction of the rigid cutoff wall 1 and the flexible cutoff wall 2. After the steel formwork is pulled out, a structural gap is created between the rigid cutoff wall 1 and the flexible cutoff wall 2. Therefore, the expansive material is used to actively compact the cracks, compensate for concrete shrinkage, and reduce stress concentration at the connection between different materials.

[0041] The prestressed tie rod 6 is tensioned in stages after the concrete strength of the rigid anti-seepage wall 1 or pile cap 3 is greater than 80% of the design value, and the duct grouting is completed within 24 hours after tensioning.

[0042] Because the lateral pressure of the slope will cause the slope protection toe 4 to tend to slide outward, it will generate horizontal tensile force at the turning point where it connects with the rigid anti-seepage wall 1. At the same time, the anti-seepage wall needs to resist the seepage force, which further exacerbates the tensile force. The self-weight of the slope protection toe 4 and the vertical load of the slope backfill soil will form downward compressive stress at the turning point. The combination of the horizontal force of water impact and soil pressure with the vertical force of self-weight and compressive stress leads to a relative sliding tendency at the interface of the turning point, generating shear force. Therefore, the prestressed steel bars should protrude outward and bend upward to form reverse compressive stress at the turning point, offsetting the tensile stress, while enhancing the shear resistance of the interface and preventing cracking at the turning point.

[0043] During the overall construction process, it is necessary to wait for the plastic concrete to pass the penetration resistance test to confirm that there is no obvious deformation on the wall surface and no marks left when pressed before carrying out the hole enlargement and trenching operation of the rigid wall.

[0044] Although the final setting time is relatively long, the installation of the steel cage and the pouring of concrete for the rigid wall need to be completed after the initial setting of the flexible wall and before the final setting. This is to avoid the flexible wall having too high a strength after final setting, which would cause "cold joints" at the junction of the rigid and flexible walls and affect the overall seepage prevention effect.

[0045] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The protection scope of this utility model should be the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. A cantilevered rigid-flexible seepage-proof structure, characterized in that: Including flexible The seepage barrier (2) is made of plastic concrete and is vertically buried in the geological soil layer (5). The rigid seepage barrier (1) is coaxially set above the flexible seepage barrier (2), and the two are connected by a wedge groove structure to form an integrated rigid-flexible seepage barrier structure. The pile cap (3) is connected to the top of the rigid seepage barrier (1), and its upper surface is flush with the ground. It is used to connect the rigid seepage barrier (1) into a whole. The cantilever side of the rigid seepage barrier (1) is provided with slope protection and toe protection (4).

2. The cantilevered rigid-flexible seepage-proof structure according to claim 1, characterized in that: The flexible seepage barrier (2) has a multi-level stepped protrusion (201) at the top. The rigid anti-seepage wall (1) has a matching multi-level stepped groove (101) at the bottom. Multi-level stepped protrusions (201) are embedded in multi-level stepped grooves (101), and the rigid anti-seepage wall (1) and the flexible anti-seepage wall (2) form a coaxial interlocking connection structure.

3. The cantilevered rigid-flexible seepage-proof structure according to claim 2, characterized in that: The number of steps in the multi-level stepped protrusions (201) at the top of the flexible seepage barrier (2) is 2-3.

4. The cantilevered rigid-flexible seepage-proof structure according to claim 2, characterized in that: The height difference between adjacent steps is configured to be 1 / 3 to 1 / 2 of the smaller thickness of the rigid cutoff wall (1) and the flexible cutoff wall (2).

5. The cantilevered rigid-flexible seepage-proof structure according to claim 2, characterized in that: Each step has an outward slope on its sidewall, and the angle between its inclination and the vertical axis of the flexible impermeable wall (2) is 5-8°.

6. The cantilevered rigid-flexible seepage-proof structure according to claim 1, characterized in that: Expansive mortar (8) is provided at the connection gap between the multi-level stepped protrusion (201) at the top of the flexible seepage barrier (2) and the multi-level stepped groove (101) at the bottom of the rigid seepage barrier (1).

7. The cantilevered rigid-flexible seepage-proof structure according to claim 1, characterized in that: The end of the slope protection and toe protection (4) is anchored to the upper cantilever side of the rigid anti-seepage wall (1) by prestressed tie rod (6); Alternatively, the end of the slope protection toe (4) is cantilevered and anchored to the pile cap (3) by a prestressed tie rod (6).

8. The cantilevered rigid-flexible seepage-proof structure according to claim 7, characterized in that: The slope protection and toe protection (4) are anchored to the pile cap (3) at a height between the rigid anti-seepage wall (1) and the cantilever side, and a waterproof facing (7) is also provided.

9. The cantilevered rigid-flexible seepage-proof structure according to claim 1, characterized in that: The prestressing direction of the prestressed tie rod (6) is configured such that the prestressed steel bar bulges outward and bends upward on the cantilever side.

10. The cantilevered rigid-flexible seepage-proof structure according to claim 1, characterized in that: The slope protection (4) includes a riprap toe protection (401) embedded in the geological soil layer (5) on the cantilever side and a slope protection section (402) covering the slope.

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