Construction connection method for concrete diaphragm wall and composite geomembrane

Abstract

The invention discloses a construction connection method for a concrete diaphragm wall and a composite geomembrane. The construction connection method comprises the steps from S1 to S7. After construction, the composite geomembrane and the concrete anti-seepage wall are fixed through the bolts and the nuts, and the fixed position is filled and sealed through the cap concrete and the second-stage concrete, so that connection between the composite geomembrane and the concrete anti-seepage wall is very tight and stable, and water is difficult to permeate from the connecting position; therefore, the safety and durability of the project are improved, and the project damage caused by water leakage at the joint can be effectively prevented.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy and hydropower engineering, and in particular to a construction connection method of a concrete anti-seepage wall and a composite geomembrane. Background Art

[0002] In water conservancy and hydropower projects, water leakage threatens project safety, stability, and durability, and is particularly problematic in areas with complex geology and abundant groundwater. Traditional anti-seepage measures are ineffective: anti-seepage materials have poor adaptability, clay is easily eroded by water flow, and concrete bonds poorly at faults and is prone to shrinkage cracks. Construction techniques are highly limited, making it difficult to densely fill underground caverns. Dewatering projects in areas with high groundwater levels are costly and difficult, and may damage surrounding facilities. Anti-seepage structures lack integrity, with loose connections between anti-seepage units and with the rock and soil, leading to performance degradation after long-term erosion and erosion. Furthermore, their responsiveness to geological changes is weak, with designs often considering only the current geology. When geological changes such as earthquakes and rainfall occur, it is difficult to adapt to and address new leakage issues in a timely manner. Therefore, the development of efficient and reliable anti-seepage connection methods is urgent. These methods can improve project safety and stability, extend their service life, and provide strong support for protecting people's lives and property and promoting sustainable economic and social development. Summary of the Invention

[0003] The purpose of the present invention is to address the above-mentioned shortcomings and provide a construction connection method for a concrete cut-off wall and a composite geomembrane, so as to increase the tightness of the connection between the concrete cut-off wall and the composite geomembrane and prevent the risk of engineering damage caused by leakage.

[0004] To solve the above technical problems, the present invention adopts the following technical solution: a construction connection method for a concrete anti-seepage wall and a composite geomembrane, comprising: S1. Install a pile driver on the foundation surface, drill holes to form grooves, and pour concrete for the underground cutoff wall after the pile holes are formed. On the above-ground part, lay slag on both sides of the corresponding concrete cutoff wall until the slag is flush with the top of the concrete cutoff wall. Continue laying the slag so that the laying height of the slag is higher than the concrete cutoff wall. At this time, a connecting groove is formed between the top of the concrete cutoff wall and the slag on both sides, and the top of the concrete cutoff wall is exposed at the connecting groove. S2. After the construction of step S1 is completed, bolts, composite geomembrane, steel plate, nuts and capping concrete are installed on the top of the connection groove and the anti-seepage wall in sequence; S3. In step S2, bolts are vertically installed on the concrete anti-seepage wall. A composite geomembrane and a steel plate are sequentially arranged on the bolts from bottom to top. The steel plate presses the bottom of the composite geomembrane. After installation, nuts are screwed onto the bolts and press the steel plate to fix them. S4. After the construction of step S2 is completed, capping concrete is poured in the connection groove. A groove is reserved at the corresponding nut and steel plate of the capping concrete. One side of the composite geomembrane is located in the groove and is arranged in a U shape. S5. After the construction of step S4 is completed, check whether the nut is tightened. If it is tightened, proceed to the next step. If it is not tightened, tighten it; S6. Pour the second phase concrete into the groove. The cap concrete is formed into a rectangular shape after pouring. S7. Place the transition material and composite geomembrane on the slag material and capping concrete. The thickness of each layer is 40cm. After laying, roll it flat and fill it layer by layer to the designed elevation.

[0005] Furthermore, the installed composite geomembrane is provided with an upwardly bent right angle on the right side for further water blocking.

[0006] Furthermore, the maximum particle size of the slag material is ≤300mm, wherein the content of particles less than 20mm in the slag material does not exceed 15%, the content of particles greater than 200mm does not exceed 15%, the relative density is greater than 0.80, and the compacted dry density is ≥1.95g / cm 3 , permeability coefficient 1~5×10 -3 The thickness of the soil is 40cm, and it is rolled 4 to 6 times using a self-propelled smooth wheel roller of more than 15t.

[0007] Furthermore, the concrete anti-seepage wall is C25 concrete with a thickness of 0.8m.

[0008] Furthermore, the cap concrete is C25 concrete, and the cap concrete is cast in one-time casting.

[0009] Furthermore, the nut is AM20, the steel plate is 30cm×20cm×0.5cm and is arranged throughout the length; the bolt is φ20, L=0.6m, with an external leakage of 0.2m and a spacing of 1m.

[0010] Furthermore, the second phase concrete is C25 concrete, and the second phase concrete is cast in a one-time casting manner, after the composite geomembrane, nuts, steel pads, and bolts are installed.

[0011] Furthermore, the particle size of the transition material is 0.074 mm to 5 mm, the relative density is greater than 0.80, and the compacted dry density is greater than or equal to 1.85 g / cm 3 , permeability coefficient 5~10×10 -3 ; The transition material and the composite geomembrane are flattened by using a self-propelled smooth wheel roller of more than 15 tons for 4 to 6 times.

[0012] Furthermore, the composite geomembrane is arranged in a manner of two cloths and one membrane, with specifications of 300g / 0.75mmPE / 300g and a unit area mass of ≥1050g / m 2 , membrane width ≥ 4m, permeability coefficient < 1×10 -11 cm / s, and the bending slope is 1:1.6.

[0013] Furthermore, the step S3 further includes a fastening device, which includes: A fastening assembly, comprising a mounting frame, an adjusting nut, and a fastening frame that are sequentially sleeved onto the bolt from bottom to top, wherein the mounting frame and the fastening frame are fixed by fasteners, and both sides of the fasteners are hooked to the connection between the steel base plate and the composite geomembrane; Rotating the nut and the adjusting nut in opposite directions can respectively cause them to descend and ascend, and can bring the fastening frame and the steel backing plate closer to each other.

[0014] The beneficial effects of the present invention are embodied in: After construction, the composite geomembrane is fixed to the concrete anti-seepage wall by bolts and nuts, and the fixing points are sealed by capping concrete and secondary concrete filling, so that the connection between the composite geomembrane and the concrete anti-seepage wall is very tight and stable, making it difficult for water to penetrate from the connection, thereby increasing the safety, stability and durability of the project, and can effectively prevent project damage caused by water leakage at the connection. In addition, this construction method is suitable for a variety of complex geological conditions and groundwater environments, and has high practicality and applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a construction schematic diagram of the present invention; Figure 2 Schematic diagram of the installation of the composite geomembrane of the present invention; Figure 3 A schematic diagram of the arrangement of the fastening assembly in the present invention; Figure 4 For the present invention Figure 3 A partial enlarged view shown.

[0016] In the picture: 1. Transition material; 2. Composite geomembrane; 3. Cap concrete; 4. Second-phase concrete; 5. Nuts; 6. Steel plate; 7. Bolts; 8. Concrete anti-seepage wall; 9. Stone slag; 10. Fastening assembly; 101. Mounting frame; 102. Adjusting nut; 103. Fastening frame; 104. Fasteners. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] See also Figure 1-4 The present invention discloses a construction connection method for a concrete anti-seepage wall and a composite geomembrane, comprising: S1. Install a pile driver on the foundation surface, drill holes into grooves, and pour concrete for the underground cutoff wall after the pile holes are formed. On the above-ground part, lay slag 9 on both sides of the corresponding concrete cutoff wall 8 until the slag 9 is flush with the top of the concrete cutoff wall 8 and continue laying. Make the laying height of the slag 9 higher than the concrete cutoff wall 8. At this time, a connecting groove is formed between the top of the concrete cutoff wall 8 and the slag 9 on both sides, and the top of the concrete cutoff wall 8 is exposed at the connecting groove; S2. After the construction of step S1 is completed, bolts 7, composite geomembrane 2, steel plate 6, nuts 5 are installed in sequence on the top of the connection groove and the anti-seepage wall 8, and the capping concrete 3 is poured; S3. In step S2, the bolt 7 is vertically installed on the concrete cut-off wall 8. The composite geomembrane 2 and the steel plate 6 are arranged on the bolt 7 from bottom to top. The steel plate 6 presses the bottom of the composite geomembrane 2. After installation, the nut 5 is screwed onto the bolt 7 and presses the steel plate 6 to fix it; S4. After the construction of step S2 is completed, cap concrete 3 is poured in the connection groove. A groove is reserved at the cap concrete 3 corresponding to the nut 5 and the steel plate 6. One side of the composite geomembrane 2 is located in the groove, and the groove is L-shaped or U-shaped, preferably U-shaped. S5. After step S4 is completed, check whether the nut 5 is tightened. If tightened, proceed to the next step. If not, tighten it. S6, pouring the second phase concrete 4 in the groove, the cap concrete 3 is poured into a rectangular shape; S7. Lay the transition material 1 and the composite geomembrane 2 on the slag material 9 and the cap concrete 3. The thickness of the soil is 40 cm, and the corresponding number of layers can be laid according to the actual situation. After laying, flatten and roll them, and fill them layer by layer to the designed elevation.

[0019] In specific implementation, after the construction is completed, the composite geomembrane 2 is fixed to the concrete anti-seepage wall 8 by bolts 7 and nuts 5, and the side of the composite geomembrane 2 located in the groove is L-shaped and fits tightly with the inner wall of the cap concrete 3 and the steel pad 6. The fixing point cooperates with the filling and sealing of the cap concrete 3 and the second phase concrete 4, so that the connection between the composite geomembrane 2 and the concrete anti-seepage wall 8 is very tight and stable, making it difficult for water to penetrate from the connection, thereby increasing the safety and durability of the project, and can effectively prevent damage to the project caused by water leakage at the connection.

[0020] In addition, the above construction process is very simple and convenient, and it does not increase excessive construction costs, so it is easy to implement in practice.

[0021] In one embodiment, the installed composite geomembrane 2 has an upwardly bent right angle at its bottom, which can further block water.

[0022] In one embodiment, the maximum particle size of the slag material 9 is ≤300 mm, wherein the content of particles less than 20 mm in the slag material 9 does not exceed 15%, the content of particles greater than 200 mm does not exceed 15%, the relative density is greater than 0.80, and the compacted dry density is ≥1.95 g / cm 3 , permeability coefficient 1~5×10 -3 The thickness of each layer of soil is 40cm, and a self-propelled flat roller of more than 15t is used for 4 to 6 times.

[0023] In a specific implementation, by providing the above-mentioned slag material 9, and the slag material 9 having a smaller particle size, the soil layer can be pressed more densely, the wheel angle is small, and the composite geomembrane is prevented from being punctured, thereby improving the safety of the composite geomembrane 2.

[0024] In one embodiment, the concrete cut-off wall 8 is made of C25 concrete and has a thickness of 0.8 m.

[0025] In one embodiment, the capping concrete 3 is C25 concrete, and the capping concrete 3 is cast in one step.

[0026] In one embodiment, the nut 5 is AM20, the steel plate 6 is 30cm×20cm×0.5cm and is arranged throughout the length; the bolt is φ20, L=0.6m, with an external leakage of 0.2m and a spacing of 1m.

[0027] In one embodiment, the second-phase concrete 4 is C25 concrete, and the second-phase concrete 4 is cast in one-time casting after the composite geomembrane 2, nuts 5, steel pads 6, and bolts 7 are installed.

[0028] In one embodiment, the particle size of the transition material 1 is 0.074 mm to 5 mm, the relative density is greater than 0.80, and the compacted dry density is greater than 1.85 g / cm 3, permeability coefficient 5~10×10 -3 The transition material 1 and the composite geomembrane 2 are flattened by a self-propelled flattening roller of more than 15 tons, and the number of flattening times is 4 to 6 times.

[0029] In one embodiment, the composite geomembrane 2 is provided in a manner of two cloths and one membrane, with specifications of 300g / 0.75mmPE / 300g, and a unit area mass of ≥1050g / m 2 , membrane width ≥ 4m, permeability coefficient < 1×10 -11 cm / s, and the bending slope is 1:1.6.

[0030] In one embodiment, the above-mentioned step S3 also includes a fastening device, which includes a fastening assembly 10, and the fastening assembly 10 includes a mounting frame 101, an adjusting nut 102 and a fastening frame 103 that are sequentially sleeved on the bolt 7 from bottom to top, wherein the mounting frame 101 and the fastening frame 103 are fixed by a fastener 104, which can be a bolt member, and both sides of the fastener 104 are hooked to the connection between the steel base plate 6 and the composite geomembrane 2.

[0031] In the specific implementation, the two sides of the fastening frame 103 are first hooked at the connection between the steel base plate 6 and the composite geomembrane 2. Then, the staff rotates the nut 5 and the adjusting nut 102 in opposite directions to move the nut 5 downward on the bolt 7 and the adjusting nut 102 upward on the adjusting nut 102. At this time, the fastening frame 103 and the steel base plate 6 are close to each other, thereby further improving the tightness of the fit between the steel base plate 6 and the composite geomembrane 2. Combined with the subsequent pouring of the cap concrete 3 and the second phase concrete 4, the sealing and anti-leakage ability of this place can be effectively enhanced.

[0032] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), such directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] In addition, "plurality" means two or more.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A construction connection method for a concrete cut-off wall and a composite geomembrane, characterized in that: include: S1. Install a pile driver on the foundation surface, drill holes to form grooves, and pour underground anti-seepage wall concrete after forming pile holes. On the ground part, slag (9) is laid on both sides of the corresponding concrete anti-seepage wall (8) until the slag (9) is flush with the top of the concrete anti-seepage wall (8). Then continue laying, so that the laying height of the slag (9) is higher than the concrete anti-seepage wall (8). At this time, a connecting groove is formed between the top of the concrete anti-seepage wall (8) and the slag (9) on both sides, and the top of the concrete anti-seepage wall (8) is exposed at the connecting groove; S2. After the construction of step S1 is completed, bolts (7), composite geomembrane (2), steel pad (6), nut (5) are installed in sequence on the top of the connection groove and the anti-seepage wall (8), and the capping concrete (3) is poured; S3. In step S2, the bolt (7) is vertically installed on the concrete anti-seepage wall (8), and the composite geomembrane (2) and the steel pad (6) are arranged on the bolt (7) from bottom to top. The steel pad (6) presses the bottom of the composite geomembrane (2). After the installation is completed, the nut (5) is screwed onto the bolt (7) and presses the steel pad (6) to fix it; S4. After the construction of step S2 is completed, capping concrete (3) is poured in the connection groove, and a groove is reserved at the corresponding nut (5) and steel plate (6) of the capping concrete (3). One side of the composite geomembrane (2) is located in the groove, and it is arranged in a U shape; S5. After the construction of step S4 is completed, check whether the nut (5) is tightened. If it is tightened, proceed to the next step. If it is not tightened, tighten it; S6, pouring the second phase concrete (4) in the groove, and the cap concrete (3) is formed into a rectangular shape after pouring; S7. Lay the transition material (1) and the composite geomembrane (2) on the slag material (9) and the capping concrete (3) in a level manner. The thickness of each layer of soil is 40 cm. After laying, roll the soil flat and fill it layer by layer to the designed elevation.

2. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The installed composite geomembrane is provided with an upwardly bent right angle on the right side for further water blocking.

3. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The maximum particle size of the slag material (9) is ≤300 mm, wherein the content of particles <20 mm in the slag material (9) does not exceed 15%, the content of particles >200 mm does not exceed 15%, the relative density is >0.80, and the compacted dry density is ≥1.95 g / cm 3 , permeability coefficient 1~5×10 -3 The thickness of the soil is 40cm, and it is rolled 4 to 6 times using a self-propelled smooth wheel roller of more than 15t.

4. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The concrete anti-seepage wall (8) is made of C25 concrete and has a thickness of 0.8m.

5. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The cap concrete (3) is C25 concrete, and the cap concrete (3) is cast in one-time casting.

6. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The nut (5) is AM20, and the steel plate (6) is 30cm×20cm×0.5cm arranged throughout the length; the bolt is φ20, L=0.6m, with an external leakage of 0.2m and a spacing of 1m.

7. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The second-phase concrete (4) is C25 concrete, and the second-phase concrete (4) is cast in a one-time casting manner, after the composite geomembrane (2), the nut (5), the steel pad (6), and the bolt (7) are installed.

8. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The particle size of the transition material (1) is 0.074 mm to 5 mm, the relative density is greater than 0.80, and the compacted dry density is greater than or equal to 1.85 g / cm 3 , permeability coefficient 5~10×10 -3 ; The transition material (1) and the composite geomembrane (2) are flattened by using a self-propelled smooth wheel roller with a weight of more than 15 tons for 4 to 6 times.

9. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The composite geomembrane (2) is arranged in a manner of two cloths and one membrane, and its specifications are 300g / 0.75mmPE / 300g, and the unit area mass is ≥1050g / m 2 , membrane width ≥ 4m, permeability coefficient < 1×10 -11 cm / s, and the bending slope is 1:1.

6.

10. The construction connection method of a concrete cut-off wall and a composite geomembrane according to claim 1, characterized in that: The step S3 further includes a fastening device, which includes: A fastening assembly (10), the fastening assembly (10) comprising a mounting frame (101), an adjusting nut (102) and a fastening frame (103) which are sequentially sleeved onto the bolt (7) from bottom to top, the mounting frame (101) and the fastening frame (103) being fixed by a fastener (104), and both sides of the fastener (104) being hooked to the connection between the steel backing plate (6) and the composite geomembrane (2); Rotating the nut (5) and the adjusting nut (102) in opposite directions can cause them to descend and ascend respectively, thereby bringing the fastening frame (103) and the steel backing plate (6) closer to each other.

Images