Anti-seepage system suitable for earth rock cofferdam

Abstract

The utility model relates to the technical field of cofferdam seepage prevention, in particular to a seepage prevention system suitable for an earth rock cofferdam. An anti-seepage system suitable for an earth rock cofferdam comprises a steel sheet pile and a jet grouting pile, the steel sheet pile extends into the jet grouting pile, the jet grouting pile extends into bed rock below the cofferdam, and the steel sheet pile is arranged above the jet grouting pile. The jet grouting piles stretch into the bedrock, compared with the mode that steel pipe piles are driven into the bedrock, the jet grouting piles can be driven into the bedrock more quickly and easily, and construction is easier and more convenient. And by arranging the jet grouting piles, the problem that steel sheet piles are not suitable for deeper anti-seepage areas can be solved. The jet grouting piles are connected with the ends of the steel sheet piles, the steel pipe piles are arranged above the jet grouting piles, the steel pipe piles are arranged in the soil layer below the cofferdam, use of the jet grouting piles can be reduced as much as possible, and construction cost can be saved. And pollution can be reduced, the environment is protected, and the concept of green construction is met.

Description

Technical Field

[0001] The utility model relates to the technical field of anti-seepage of cofferdams, in particular to an anti-seepage system suitable for earth-rock cofferdams. Background Art

[0002] In the construction of water conservancy and water transport projects, the cofferdam is generally used to divert water and ensure that the construction area meets the conditions for dry construction. As an important temporary structure in water conservancy and water transport projects, the cofferdam is an important barrier for the construction of the project foundation pit. Its ability to prevent water seepage and divert water directly affects the construction cost, project schedule and construction safety. In addition, during the construction period, the cofferdam needs to go through the test of flood prevention and flood control. If a cofferdam fails, the consequences will be very serious.

[0003] There are many types of cofferdams, among which earth-rock dam cofferdams are made of local materials and are widely used in water conservancy and water transport projects. Common earth-rock cofferdam dam anti-seepage methods mainly include steel sheet pile anti-seepage walls and high-pressure rotary jet grouting methods. Existing cofferdam anti-seepage methods mostly use a single treatment method, which has many disadvantages:

[0004] Steel sheet pile anti-seepage wall: It has good anti-seepage effect and certain anti-deformation ability. However, when the anti-seepage treatment is deep, it is very difficult to drive and remove the steel sheet piles, which affects the construction efficiency and the anti-seepage effect is difficult to meet the requirements.

[0005] High-pressure rotary jet grouting: The construction takes up less space, has less vibration and lower noise, but it is easy to pollute the environment and has higher costs. It is not suitable for special soils that cannot solidify the sprayed slurry. Utility Model Content

[0006] The purpose of the utility model is to solve the problems in the prior art that the use of steel sheet pile anti-seepage walls for cofferdam anti-seepage is not suitable for deeper areas, and the use of high-pressure rotary jet grouting for cofferdam anti-seepage is easy to pollute the environment and has high costs, and to provide an anti-seepage system suitable for earth-rock cofferdams.

[0007] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0008] A seepage prevention system suitable for earth-rock cofferdams comprises steel sheet piles and jet grouting piles, wherein the steel sheet piles extend into the jet grouting piles, the jet grouting piles extend into bedrock below the cofferdam, and the steel sheet piles are arranged above the jet grouting piles.

[0009] The steel sheet piles extend into the jet grouting piles, which is beneficial to improve the anti-seepage effect and can also fix the steel sheet piles as much as possible. Compared with driving the steel pipe piles into the bedrock, the jet grouting piles extend into the bedrock, which can be driven into the bedrock more quickly and easily, making the construction easier. By setting up the jet grouting piles, the problem that the steel sheet piles are not suitable for deeper anti-seepage areas can be solved. The jet grouting piles and the steel sheet piles are connected at the ends, and the steel pipe piles are set above the jet grouting piles. The steel pipe piles are in the soil layer below the cofferdam, which can reduce the use of the jet grouting piles as much as possible, which is beneficial to saving construction costs. It can also reduce pollution, protect the environment, and conform to the concept of green construction.

[0010] As a preferred embodiment of the present invention, the length of the steel sheet pile extending into the rotary jet pile is greater than 1 m.

[0011] If the length of the steel sheet pile extending into the rotary jet grouting pile is greater than 1m, it is possible to avoid as much as possible the offset between the steel sheet pile and the rotary jet grouting pile, which would affect the anti-seepage effect.

[0012] As a preferred solution of the utility model, the jet grouting pile is a cylindrical pile, and the distance between the centers of two adjacent jet grouting piles is smaller than the diameter of the jet grouting pile.

[0013] Parts of two adjacent jet-jet piles are staggered or overlapped with each other, which can increase the connection strength and integrity between the piles, prevent groundwater seepage and improve the bearing capacity.

[0014] As a preferred solution of the utility model, the center distance between two adjacent jet grouting piles is no more than 5 / 6 of the diameter of the jet grouting piles.

[0015] The center distance between two adjacent jet grouting piles shall not exceed 5 / 6 of the diameter of the jet grouting piles, which can ensure the improvement of anti-seepage effect as much as possible and also improve the structural stability.

[0016] As a preferred embodiment of the present invention, the diameter of the jet grouting pile is greater than twice the length of the steel sheet pile unit, and the ends of a plurality of the steel sheet pile units are connected to form a steel sheet pile.

[0017] Multiple steel sheet pile units are interlocked and connected to form steel sheet piles. The length of the steel sheet pile unit is consistent with the length direction of the steel sheet pile. The diameter of the jet grouting pile is greater than twice the length of the steel sheet unit, which can minimize the gap between the jet grouting pile and the steel sheet pile, which is conducive to ensuring the quality of anti-seepage.

[0018] As a preferred solution of the present utility model, the steel sheet pile is arranged on the backwater side of the jet grouting pile.

[0019] If the distance from the steel sheet pile to the water-facing side of the rotary jet pile is greater than the distance from the steel sheet pile to the water-retaining side of the rotary jet pile, the bearing pressure of the steel sheet pile can be reduced, so that the water pressure in the gaps of the steel sheet pile is reduced, which is beneficial to improving the anti-seepage effect.

[0020] As a preferred embodiment of the present invention, the distance from the steel sheet pile to the connecting line of the centers of the plurality of jet grouting piles is not less than 1 / 8 of the maximum cross-sectional dimension of the jet grouting pile.

[0021] When the cross-section of the jet grouting pile is rectangular, the maximum cross-sectional dimension is the length of the rectangle; when the cross-section of the jet grouting pile is circular, the maximum cross-sectional dimension is the diameter of the circle.

[0022] As a preferred solution of the present utility model, the gap between the steel sheet pile and the rotary jet grouting pile is filled with concrete.

[0023] Due to the cross-sectional shape of the steel sheet pile, there is a possibility of a gap between the steel sheet pile and the jet grouting pile. Filling the gap between the steel sheet pile and the jet grouting pile with concrete facilitates operation.

[0024] As a preferred solution of the utility model, the gap between the steel sheet pile and the rotary jet pile is filled with a water stop strip that expands when exposed to water.

[0025] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0026] An anti-seepage system suitable for earth-rock cofferdams is provided with steel sheet piles and jet grouting piles. The ends of the steel sheet piles and the jet grouting piles are connected. The steel sheet piles are above the jet grouting piles. The jet grouting piles extend into the bedrock below the cofferdam. Compared with driving steel pipe piles into the bedrock, they can be driven into the bedrock more quickly and easily, making the construction easier. In addition, when steel sheet piles are provided, the steel pipe piles are in the soil layer below the cofferdam, which can reduce the use of jet grouting piles as much as possible, which is conducive to saving construction costs. It can also reduce pollution, protect the environment, and comply with the concept of green construction. This device solves the problems existing in the prior art that the use of steel sheet pile anti-seepage walls for cofferdam anti-seepage is not suitable for deeper areas, and the use of high-pressure jet grouting for cofferdam anti-seepage is easy to pollute the environment and has high costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a top view of an anti-seepage system suitable for earth-rock cofferdam in Example 1;

[0028] Figure 2 It is a comparison diagram of an anti-seepage system suitable for earth-rock cofferdam in Example 1 and the prior art (all the figures are side views).

[0029] Icon: 1-Steel sheet pile, 2-Jet grouting pile, 3-Gap. DETAILED DESCRIPTION

[0030] The utility model is described in detail below in conjunction with the accompanying drawings.

[0031] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0032] Example 1

[0033] like Figure 1-Figure 2 As shown, an anti-seepage system suitable for earth-rock cofferdams includes steel sheet piles 1 and jet grouting piles 2. The steel sheet piles 1 and the jet grouting piles 2 are connected at their ends. The jet grouting piles 2 extend into the bedrock below the cofferdam, and the steel sheet piles 1 are arranged above the jet grouting piles 2.

[0034] The jet grouting pile 2 extends into the bedrock, and can be driven into the bedrock more quickly and easily than driving the steel pipe pile into the bedrock, making the construction easier. By setting the jet grouting pile 2, the problem that the steel sheet pile 1 is not suitable for deeper anti-seepage areas can be solved. The jet grouting pile 2 is connected to the end of the steel sheet pile 1, and a steel pipe pile is set above the jet grouting pile 2. The steel pipe pile is in the soil layer below the cofferdam, which can reduce the use of the jet grouting pile 2 as much as possible, which is conducive to saving construction costs. It can also reduce pollution, protect the environment, and conform to the concept of green construction.

[0035] The steel sheet pile 1 extends into the rotary grouting pile 2. The length of the steel sheet pile 1 extending into the rotary grouting pile 2 is greater than 1 m.

[0036] The jet grouting pile 2 is a cylindrical pile, and the distance between the centers of two adjacent jet grouting piles 2 is less than the diameter of the jet grouting pile 2. The center distance between two adjacent jet grouting piles 2 is no more than 5 / 6 of the diameter of the jet grouting pile 2. The diameter of the jet grouting pile 2 is greater than twice the length of the steel sheet pile unit, and the ends of multiple units are connected to form a steel sheet pile 1. In this embodiment, the diameter of the jet grouting pile 2 is 1.2m, and the center distance between two adjacent jet grouting piles 2 is 0.8m

[0037] like Figure 2 As shown, the steel sheet pile 1 is arranged on the backwater side of the jet grouting pile 2. The distance between the steel sheet pile 1 and the center of the plurality of jet grouting piles 2 is not less than 1 / 8 of the maximum cross-sectional dimension of the jet grouting pile 2. In this embodiment, the distance between the steel sheet pile 1 and the center of the jet grouting pile 2 is 20 cm. If the distance between the steel sheet pile 1 and the water-facing side of the jet grouting pile 2 is greater than the distance between the steel sheet pile 1 and the backwater side of the jet grouting pile 2, the bearing pressure of the steel sheet pile 1 can be reduced, so that the water pressure at the gap of the steel sheet pile 1 is reduced, which is beneficial to improve the anti-seepage effect.

[0038] like Figure 2 As shown, compared with the existing system that only sets steel sheet piles 1, this system can drive deeper into the soil; compared with the existing technology that only sets jet grouting piles 2, only one smaller jet grouting pile 2 can be set, which is beneficial to saving construction costs. It can also reduce pollution, protect the environment, and conform to the concept of green construction.

[0039] like Figure 1 As shown, the gap 3 between the steel sheet pile 1 and the jet-jet pile 2 is filled with concrete, and a water stop strip that swells when exposed to water can also be filled in the gap 3 between the steel sheet pile 1 and the jet-jet pile 2.

[0040] When constructing this system, the following steps are performed:

[0041] S1, Steel Sheet Pile 1 Driving Construction

[0042] The steel sheet pile 1 uses Larsen steel sheet pile 1, and uses a crawler pile driver to vibrate the pile. During the whole process of pile sinking (insertion and repeated driving), it should be ensured that the vibrating hammer, the clamp, and the steel sheet pile 1 are on the same vertical axis to reduce eccentric pile sinking and reduce pile displacement.

[0043] S2, Jet Grouting Pile 2 Construction

[0044] Equipment is installed on the top of the cofferdam, holes are drilled according to the measured and marked positions, and cement slurry is prepared for spraying according to design requirements after the holes are formed.

[0045] S3. Overlap construction of steel sheet pile 1 and rotary jet grouting pile 2.

[0046] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An anti-seepage system suitable for earth-rock cofferdam, characterized in that: It comprises a steel sheet pile (1) and a jet grouting pile (2), wherein the steel sheet pile (1) extends into the jet grouting pile (2), the jet grouting pile (2) extends into the bedrock below the cofferdam, and the steel sheet pile (1) is arranged above the jet grouting pile (2).

2. The anti-seepage system suitable for earth-rock cofferdam according to claim 1, characterized in that: The length of the steel sheet pile (1) extending into the jet grouting pile (2) is greater than 1 m.

3. The anti-seepage system suitable for earth-rock cofferdam according to claim 1, characterized in that: The jet grouting pile (2) is a cylindrical pile, and the distance between the centers of two adjacent jet grouting piles (2) is smaller than the diameter of the jet grouting pile (2).

4. The anti-seepage system suitable for earth-rock cofferdam according to claim 3, characterized in that: The center distance between two adjacent jet grouting piles (2) is no greater than 5 / 6 of the diameter of the jet grouting pile (2).

5. The anti-seepage system suitable for earth-rock cofferdam according to claim 3, characterized in that: The diameter of the jet-jet pile (2) is greater than twice the length of the steel sheet pile unit, and the ends of a plurality of the steel sheet pile units are connected to form a steel sheet pile (1).

6. An anti-seepage system suitable for earth-rock cofferdam according to any one of claims 1 to 5, characterized in that: The steel sheet pile (1) is arranged on the side of the jet grouting pile (2) facing away from water.

7. The anti-seepage system suitable for earth-rock cofferdam according to claim 6, characterized in that: The distance between the steel sheet pile (1) and the connecting line of the centers of the plurality of jet grouting piles (2) is not less than 1 / 8 of the maximum cross-sectional dimension of the jet grouting pile (2).

8. An anti-seepage system suitable for earth-rock cofferdam according to any one of claims 1 to 5, characterized in that: The gap (3) between the steel sheet pile (1) and the jet-jet pile (2) is filled with concrete.

9. An anti-seepage system suitable for earth-rock cofferdam according to any one of claims 1 to 5, characterized in that: The gap (3) between the steel sheet pile (1) and the jet grouting pile (2) is filled with a water stop strip that swells when exposed to water.

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