Construction method of concrete anti-seepage wall

Abstract

The present invention discloses a method for constructing a concrete anti-seepage wall in the field of water conservancy and hydropower engineering, comprising the following steps: first excavating a phase I groove, installing support templates on the left and right sides of the phase I groove, pouring the phase I groove, then taking out the support template, then excavating a phase II groove, installing support templates on the left and right sides of the phase II groove, taking out the support template after pouring, and finally pouring the space left by the support templates in the phase I groove and the phase II groove, and connecting the wall sections of the phase I groove and the phase II groove. The present invention uses the first support template and the second support template to leave a filling space between the wall sections of the phase I groove and the phase II groove, and at the same time, the end face of the wall section is tortuously processed, so that after pouring concrete in the filling space, the contact area between adjacent wall sections can be increased, so that cracks penetrating the anti-seepage wall are less likely to appear at the connection part of the wall sections, and at the same time, the seepage path of the connection part between the wall sections is increased, thereby improving the anti-seepage effect of the connection part of the wall sections.

Description

Technical Field

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

[0002] Concrete anti-seepage wall is an underground continuous wall with anti-seepage function formed by using drilling and trenching machinery to solidify the wall with mud in loose and permeable foundation or dam (weir) body, digging grooves or interlocking pile holes, and then pouring underwater concrete in the grooves or backfilling other anti-seepage materials. It is an engineering measure to prevent leakage, ensure foundation stability and dam safety.

[0003] In the prior art, anti-seepage walls are generally constructed in a segmented manner, that is, a circular hole or a slot hole is poured with concrete to form a wall segment, and then many wall segments are connected to form a whole wall. The top of the wall is connected to the anti-seepage body of the dam, and the two ends are connected to the anti-seepage facilities on the shore. The bottom is embedded in the bedrock or relatively impermeable strata to a certain depth, which can cut off or reduce the seepage water flow in the foundation. The main problem with the current segmented construction method is that the anti-seepage ability at the connection is weak, because the concrete pouring time of the two adjacent wall segments is different, which leads to cracks at the connection of the wall segments, thereby affecting its anti-seepage effect. Therefore, it is necessary to provide an anti-seepage wall construction method that can improve the anti-seepage ability of the connection. Summary of the invention

[0004] In order to overcome the shortcomings of the existing segmented anti-seepage wall, such as the weak anti-seepage ability at the wall segment connection, the technical problem to be solved by the present invention is to provide a concrete anti-seepage wall construction method which can improve the anti-seepage ability at the wall segment connection.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] The concrete anti-seepage wall construction method comprises the following steps:

[0007] S1: Site leveling: Use leveling machinery to level the excavation and hole making area;

[0008] S2: Measurement and layout: Measure and lay out the construction area according to the construction drawings, and determine the size and position of the Phase I and Phase II troughs, which are set at intervals;

[0009] S3: Making a support template: making a first support template and a second support template according to the width size of the phase I trough and the phase II trough, wherein the first support template and the second support template respectively include a first column plate and a second column plate, and a first embedded column and a second embedded column respectively arranged on one side of the first column plate and the second column plate;

[0010] S4: Excavation of Phase I trench: Use drilling equipment to excavate Phase I trench on the construction ground;

[0011] S5: Install the first supporting formwork: After the first phase trench is excavated, the hole is cleaned and inspected, and then the first supporting formwork is installed on the left and right sides of the first phase trench, and the first embedded column of the first supporting formwork is directed toward the first phase trench;

[0012] S6: Phase I trough pouring: Use pouring equipment to pour concrete into the Phase I trough, and take out the first supporting formwork after the concrete has initially set;

[0013] S7: Excavation of Phase II trench: Use drilling equipment to excavate Phase II trench on the construction ground;

[0014] S8: Install the second supporting formwork: After the phase II trench is excavated, the hole is cleaned and inspected, and then the first supporting formwork is reinstalled, and the second supporting formwork is installed close to the first supporting formwork on the left and right sides of the phase II trench, and the second embedded column of the second supporting formwork is facing the phase II trench;

[0015] S9: Phase II trough pouring: pouring into the phase II trough using pouring equipment, and taking out the first support formwork and the second support formwork after the concrete has initially set;

[0016] S10: pouring the connection part: pouring concrete into the cavity formed after taking out the first supporting formwork and the second supporting formwork by using a pouring device;

[0017] S11: Acceptance: After pouring, the concrete anti-seepage wall is maintained, and then a drilling and water injection test is carried out on the anti-seepage wall. Acceptance is carried out after meeting the standards.

[0018] The construction method of the present invention is consistent with the traditional segmented construction method, except that the first support formwork and the second support formwork are added after the phase I and phase II trenches are excavated. The first support formwork and the second support formwork are mainly used to leave a filling space between the wall sections of the phase I and phase II trenches, and to make a tortuous treatment on the end faces of the wall sections of the phase I and phase II trenches, so that after pouring concrete in the filling space, the contact area between adjacent wall sections can be increased, and cracks that penetrate the anti-seepage wall are less likely to appear. At the same time, the seepage path of the connection parts between the wall sections is increased, thereby improving the anti-seepage effect of the connection parts of the wall sections.

[0019] In order to facilitate manufacturing, layout and removal, the first embedded column and the second embedded column on the first support formwork and the second support formwork are both strip convex columns arranged along the length direction of the first column plate and the second column plate, and the strip convex columns are at least two and are arranged at intervals. The strip convex columns are arranged along the length direction of the first column plate and the second column plate, so that the first support formwork and the second support formwork can be directly pulled out from above without damaging the wall section. The specific number and size of the strip convex columns are selected according to the width of the anti-seepage wall, and usually 2-3 strip convex columns are sufficient.

[0020] When manufacturing the first supporting formwork and the second supporting formwork, the same structural form can be adopted, that is, the first embedded column and the second embedded column are arranged at the same position. In order to further increase the tortuosity of the connecting part of the adjacent wall segments, a structural form can be adopted in which the first embedded column and the second embedded column are staggered when the first column plate and the second column plate of the first supporting formwork and the second supporting formwork are attached together.

[0021] Specifically, the cross-sections of the first embedded column and the second embedded column may be trapezoidal or triangular. The trapezoidal or triangular embedded columns can make the end face of the wall segment more irregular, and when pouring the connection part, the concrete can be partially embedded in the trapezoidal or triangular space of the end face of the wall segment, thereby improving the reliability of the connection between the concrete of the connection part and the wall segment, thereby improving the anti-seepage ability of the connection of the anti-seepage wall.

[0022] Furthermore, the first column plate and the second column plate are provided with an inner wall fitting column plate and an outer wall fitting column plate at both inner and outer ends and on one side facing the first embedded column and the second embedded column respectively, and the inner wall fitting column plate and the outer wall fitting column plate are both fitted with the inner wall of the excavated groove. The inner wall fitting column plate and the outer wall fitting column plate can directly provide a certain shielding effect on the side of the connection part, and can form a cross connection with the connection part in the middle, which can strengthen the connection strength of the connection part and further improve the anti-seepage ability.

[0023] In order to facilitate production, transportation and installation, the first support formwork and the second support formwork are both made of multiple sections, each section is 5-7m long, and has connecting parts at both ends. When installing, they are connected while being lowered, and can be connected by bolts or latches.

[0024] In order to facilitate the removal of the first support formwork and the second support formwork, before installing the first support formwork and the second support formwork, a concrete release agent is first applied to the first support formwork and the second support formwork on the side facing the slot. Applying the concrete release agent can reduce the friction between the first support formwork and the second support formwork and the concrete, facilitate removal, and at the same time play a certain protective role on the wall section.

[0025] The pouring equipment includes a support platform, a sliding car and a material discharge tank. The top of the support platform is provided with a slide rail, the extension direction of the slide rail is consistent with the extension direction of the concrete anti-seepage wall, the sliding car is slidably arranged on the slide rail, the material discharge tank is arranged on the sliding car, and a material discharge pipe is arranged at the bottom of the material discharge tank. The material discharge tank can slide on the support platform with the sliding car, so as to better perform concrete pouring and improve pouring efficiency.

[0026] In the specific pouring process, the following processes also need to be controlled. When pouring concrete, it is best to use anti-seepage concrete to improve the anti-seepage ability from the material itself, and meet the compressive strength greater than 5Mpa, elastic modulus greater than 1000Mpa, to ensure the rigidity requirements of the structure. During the concrete pouring process, in order to make the concrete in the anti-seepage wall stronger after pouring, the rising speed of the concrete surface in the slot is controlled at 3-5m / h. After pouring, a vibrating rod is used for vibration to make it more compact and to discharge the bubbles generated during the concrete pouring. In addition, when the pouring reaches the design elevation, it is further poured to exceed the elevation by 0.5-0.8m, which can further optimize the anti-seepage wall.

[0027] The beneficial effects of the present invention are:

[0028] 1. After the trenches of phase I and II are excavated, the first supporting formwork and the second supporting formwork are added. After pouring, a filling space can be left between the wall sections of phase I and II. At the same time, the end faces of the wall sections of phase I and II are tortuous, so that after pouring concrete in the filling space, the contact area between adjacent wall sections can be increased, making it less likely for cracks to penetrate the anti-seepage wall to appear at the connection parts of the wall sections. At the same time, the seepage path of the connection parts between the wall sections is increased, thereby improving the anti-seepage effect of the connection parts of the wall sections;

[0029] 2. The first embedded columns and the second embedded columns on the first supporting formwork and the second supporting formwork are arranged in a staggered manner and matched with a trapezoidal or triangular structure, which can further increase the irregularity of the end surface of the wall segment, thereby better embedding and connecting with the concrete at the connection part, improving the connection strength, increasing the seepage diameter, and improving the anti-seepage ability of the connection part of the anti-seepage wall;

[0030] 3. By arranging inner wall fitting column plates and outer wall fitting column plates at the inner and outer ends of the first column plate and the second column plate, a certain shielding effect can be directly provided to the side of the connection part, and a cross connection can be formed with the connection part in the middle, which can strengthen the connection strength of the connection part and further improve the anti-seepage ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A top view of the structure of the concrete anti-seepage wall of the present invention;

[0032] Figure 2 It is a structural schematic diagram of the support formwork of the present invention;

[0033] Figure 3 It is a structural schematic diagram of the support platform of the present invention;

[0034] Figure 4 For the construction of the present invention Figure 1 ;

[0035] Figure 5For the construction of the present invention Figure 2 ;

[0036] Figure 6 For the construction of the present invention Figure 3 ;

[0037] Figure 7 For the construction of the present invention Figure 4 ;

[0038] Figure 8 For the construction of the present invention Figure 5 ;

[0039] Fig. 9 For the construction of the present invention Figure 6 ;

[0040] Marked in the figure, 1- first supporting template, 2- second supporting template, 3- inner wall fitting column plate, 4- outer wall fitting column plate, 5- bracket platform, 6- sliding car, 7- unloading tank, 11- first column plate, 12- first embedded column, 21- second column plate, 22- second embedded column, 51- slide rail, 71- unloading pipe. DETAILED DESCRIPTION

[0041] The present invention is further described below in conjunction with the accompanying drawings.

[0042] The concrete cut-off wall construction method of the present invention comprises the following steps:

[0043] S1: Site leveling: Use leveling machinery to level the excavation and hole making area;

[0044] S2: Measurement and layout: Measure and lay out the construction area according to the construction drawings, and determine the size and location of the Phase I and Phase II troughs, which are set at intervals, such as Figure 4 As shown;

[0045] S3: Making a support template: Making a first support template 1 and a second support template 2 according to the width size of the phase I trough and the phase II trough, wherein the first support template 1 and the second support template 2 respectively include a first column plate 11 and a second column plate 21, and a first embedded column 12 and a second embedded column 22 respectively arranged on one side of the first column plate 11 and the second column plate 21, such as Figure 1 , Figure 2 As shown;

[0046] S4: Excavation of Phase I trench: Use drilling equipment to excavate Phase I trench on the construction ground;

[0047] S5: Install the first supporting formwork: After the first phase trench is excavated, the hole is cleaned and inspected, and then the first supporting formwork 1 is installed on the left and right sides of the first phase trench, and the first embedded column 12 of the first supporting formwork 1 faces the first phase trench, and the first column plate 11 is fitted with the end surface of the trench. Figure 5 As shown;

[0048] S6: Phase I trough pouring: Use pouring equipment to pour concrete into the phase I trough, and after the concrete is initially set, take out the first support formwork 1. Figure 6 As shown, the specific state of the initial setting of concrete is reasonably estimated according to the construction situation. In the initial setting stage of concrete, there is still a certain amount of moisture on its surface, which can reduce the friction between the first supporting formwork 1 and the concrete, ensuring that when the first supporting formwork 1 is pulled, the concrete wall section will not collapse, deform or be damaged in a large area;

[0049] S7: Excavation of Phase II trench: Use drilling equipment to excavate Phase II trench on the construction ground;

[0050] S8: Install the second supporting formwork: After the phase II trench is excavated, the hole is cleaned and inspected, and then the first supporting formwork 1 is reinstalled, and the second supporting formwork 2 is installed close to the first supporting formwork 1 on the left and right sides of the phase II trench, and the second embedded column 22 of the second supporting formwork 2 is facing the phase II trench, such as Figure 7 As shown, the first supporting formwork 1 is reinstalled to position and support the second supporting formwork 2 to prevent it from bending and deforming during the pouring process;

[0051] S9: Phase II trough pouring: Use pouring equipment to pour into the phase II trough, and after the concrete is initially set, take out the first support formwork 1 and the second support formwork 2. Figure 8 As shown;

[0052] S10: Connecting part pouring: Use pouring equipment to pour concrete into the cavity formed after taking out the first supporting formwork 1 and the second supporting formwork 2, such as Fig. 9 As shown;

[0053] S11: Acceptance: After pouring, the concrete anti-seepage wall is maintained, and then a drilling and water injection test is carried out on the anti-seepage wall. Acceptance is carried out after meeting the standards.

[0054] The construction method of the present invention is consistent with the traditional segmented construction method, except that the first support formwork and the second support formwork are added after the phase I and phase II trenches are excavated. The first support formwork and the second support formwork are mainly used to leave a filling space between the wall sections of the phase I and phase II trenches, and to make a tortuous treatment on the end faces of the wall sections of the phase I and phase II trenches, so that after pouring concrete in the filling space, the contact area between adjacent wall sections can be increased, and cracks that penetrate the anti-seepage wall are less likely to appear. At the same time, the seepage path of the connection parts between the wall sections is increased, thereby improving the anti-seepage effect of the connection parts of the wall sections.

[0055] In order to facilitate the production, layout and removal of the first support formwork 1 and the second support formwork 2, the first embedded column 12 and the second embedded column 22 on the first support formwork 1 and the second support formwork 2 are both strip convex columns arranged along the length direction of the first column plate 11 and the second column plate 21. There are at least two strip convex columns, which are arranged at intervals. The strip convex columns are arranged along the length direction of the first column plate 11 and the second column plate 21, so that the first support formwork 1 and the second support formwork 2 can be directly pulled out from above without causing damage to the wall section. The specific number and size of the strip convex columns are selected according to the width of the anti-seepage wall. Usually 2-3 strip convex columns can meet the requirements.

[0056] When manufacturing the first supporting formwork 1 and the second supporting formwork 2, the same structural form can be adopted, that is, the first embedded column 12 and the second embedded column 22 are arranged at the same position. In order to further increase the tortuosity of the connecting part of the adjacent wall sections, when the first column plate 11 and the second column plate 21 of the first supporting formwork 1 and the second supporting formwork 2 are attached together, the first embedded column 12 and the second embedded column 22 can be staggered to further increase the seepage path.

[0057] The cross-sections of the first embedded column 12 and the second embedded column 22 are trapezoidal or triangular. The trapezoidal or triangular embedded columns can make the end face of the wall segment more irregular. When pouring the connection part, the concrete can be partially embedded in the trapezoidal or triangular space of the end face of the wall segment, thereby improving the reliability of the connection between the concrete of the connection part and the wall segment, thereby improving the anti-seepage ability of the connection of the anti-seepage wall.

[0058] The preferred method of the first supporting formwork 1 and the second supporting formwork 2 is that an inner wall fitting column plate 3 and an outer wall fitting column plate 4 are respectively provided at the inner and outer ends of the first column plate 11 and the second column plate 21 and facing the first embedded column 12 and the second embedded column 22, and the inner wall fitting column plate 3 and the outer wall fitting column plate 4 are both fitted with the inner wall of the excavated groove. The inner wall fitting column plate 3 and the outer wall fitting column plate 4 can be independent plate-like structures, or they can be fixedly connected to the first column plate 11 and the second column plate 21. Figure 1As shown, the inner wall fitting column plate 3 and the outer wall fitting column plate 4 can directly provide a certain shielding effect on the side of the connection part, and can form a cross connection with the middle connection part, which can strengthen the connection strength of the connection part and further improve the anti-seepage ability.

[0059] In order to facilitate production, transportation and installation, the first support formwork 1 and the second support formwork 2 are both made of multiple sections, each section is 5-7m long, preferably 6m long, and has connecting parts at both ends. When installing, they are connected while being lowered, and can be connected by bolts, latches, connecting plates and other structures.

[0060] In order to facilitate the removal of the first support formwork 1 and the second support formwork 2, before installing the first support formwork 1 and the second support formwork 2, a concrete release agent is first applied to the first support formwork 1 and the second support formwork 2 on the side facing the slot. Applying the concrete release agent can reduce the friction between the first support formwork 1 and the second support formwork 2 and the concrete, facilitate removal, and at the same time play a certain protective role on the wall section.

[0061] The pouring equipment includes a support platform 5, a sliding car 6 and a material tank 7. A slide rail 51 is provided on the top of the support platform 5. The extension direction of the slide rail 51 is consistent with the extension direction of the concrete anti-seepage wall. The sliding car 6 is slidably arranged on the slide rail 51. The material tank 7 is arranged on the sliding car 6. A material pipe 71 is provided at the bottom of the material tank 7. The material tank 7 can slide on the support platform 5 with the sliding car 6, so as to better perform concrete pouring and improve the pouring efficiency.

[0062] In the specific pouring process, the following processes also need to be controlled. When pouring concrete, it is best to use anti-seepage concrete to improve the anti-seepage ability from the material itself, and meet the compressive strength greater than 5Mpa, elastic modulus greater than 1000Mpa, to ensure the rigidity requirements of the structure. During the concrete pouring process, in order to make the concrete in the anti-seepage wall stronger after pouring, the rising speed of the concrete surface in the slot is controlled at 3-5m / h. After pouring, a vibrating rod is used for vibration to make it more compact and to discharge the bubbles generated during the concrete pouring. In addition, when the pouring reaches the design elevation, it is further poured to exceed the elevation by 0.5-0.8m, which can further optimize the anti-seepage wall.

Claims

1. A method for constructing a concrete anti-seepage wall, characterized in that: The following steps are involved: S1: Site leveling: Use leveling machinery to level the excavation and hole making area; S2: Measurement and layout: Measure and lay out the construction area according to the construction drawings, and determine the size and position of the Phase I and Phase II troughs, which are set at intervals; S3: Making a support template: making a first support template (1) and a second support template (2) according to the width dimensions of the phase I trough and the phase II trough, wherein the first support template (1) and the second support template (2) respectively comprise a first column plate (11) and a second column plate (21), and a first embedded column (12) and a second embedded column (22) respectively arranged on one side of the first column plate (11) and the second column plate (21); S4: Excavation of Phase I trench: Use drilling equipment to excavate Phase I trench on the construction ground; S5: Installing the first supporting formwork: After the first phase trench is excavated, the hole is cleaned and inspected, and then the first supporting formwork (1) is installed on the left and right sides of the first phase trench, with the first embedded column (12) of the first supporting formwork (1) facing the first phase trench; S6: pouring of the first stage trough: pouring concrete into the first stage trough using a pouring device, and removing the first supporting formwork (1) after the concrete has initially set; S7: Excavation of Phase II trench: Use drilling equipment to excavate Phase II trench on the construction ground; S8: Installing the second supporting formwork: After the phase II trench is excavated, the hole is cleaned and inspected, and then the first supporting formwork (1) is reinstalled, and the second supporting formwork (2) is installed on the left and right sides of the phase II trench close to the first supporting formwork (1), and the second embedded column (22) of the second supporting formwork (2) is directed toward the phase II trench; S9: pouring of the phase II trough: pouring into the phase II trough using a pouring device, and after the concrete has initially set, taking out the first supporting formwork (1) and the second supporting formwork (2); S10: pouring the connection part: using a pouring device to pour concrete into the cavity formed after the first supporting formwork (1) and the second supporting formwork (2) are removed; S11： Acceptance: After pouring, the concrete anti-seepage wall is maintained, and then a drilling and water injection test is carried out on the anti-seepage wall. Acceptance is carried out after meeting the standards; The first embedded column (12) and the second embedded column (22) on the first support formwork (1) and the second support formwork (2) are both strip-shaped convex columns arranged along the length direction of the first column plate (11) and the second column plate (21). There are at least two strip-shaped convex columns, which are arranged at intervals. When the first column plate (11) and the second column plate (21) of the first support formwork (1) and the second support formwork (2) are fitted together, the first embedded column (12) and the second embedded column (22) are staggered with each other. The inner and outer ends of the first column plate (11) and the second column plate (21) and the sides facing the first embedded column (12) and the second embedded column (22) are respectively provided with an inner wall fitting column plate (3) and an outer wall fitting column plate (4). The inner wall fitting column plate (3) and the outer wall fitting column plate (4) are both fitted with the inner wall of the excavated groove.

2. The method for constructing a concrete cut-off wall according to claim 1, wherein: The cross-sections of the first embedded column (12) and the second embedded column (22) are trapezoidal or triangular.

3. The method for constructing a concrete cut-off wall according to claim 1 or 2, characterized in that: The first supporting formwork (1) and the second supporting formwork (2) are both formed by splicing together multiple sections of structure, each section of the structure is 5-7 m long and is provided with connecting parts at both ends.

4. The method for constructing a concrete cut-off wall as claimed in claim 1, wherein: Before installing the first supporting formwork (1) and the second supporting formwork (2), a concrete release agent is first applied to the first supporting formwork (1) and the second supporting formwork (2) on the side facing the inside of the slot.

5. The method for constructing a concrete cut-off wall according to claim 1, wherein: The pouring equipment comprises a support platform (5), a sliding car (6) and a material discharge tank (7); a slide rail (51) is provided on the top of the support platform (5); the extension direction of the slide rail (51) is consistent with the extension direction of the concrete anti-seepage wall; the sliding car (6) is slidably arranged on the slide rail (51); the material discharge tank (7) is arranged on the sliding car (6); and a material discharge pipe (71) is provided at the bottom of the material discharge tank (7).

6. The method for constructing a concrete cut-off wall according to claim 1, wherein: When pouring concrete, use impermeable concrete and meet the requirements of compressive strength greater than 5Mpa and elastic modulus greater than 1000Mpa.

7. The method for constructing a concrete cut-off wall according to claim 1, wherein: During the concrete pouring process, the rising speed of the concrete surface in the slot is controlled at 3-5m / h. After pouring, a vibrating rod is used for vibration. When the pouring reaches the designed elevation, further pouring is performed to make it exceed the elevation by 0.5-0.8m.

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