Cofferdam structure and cofferdam construction method
By adding a cross-shaped second tie rod and a filter assembly to the sheet pile cofferdam, the problems of deformation resistance and seepage of the sheet pile cofferdam under high water head and high dynamic water pressure were solved, the structural stability and bearing capacity were improved, and the layout space and flow capacity of the cofferdam were optimized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-08
- Publication Date
- 2026-04-10
AI Technical Summary
In existing technologies, steel sheet pile cofferdams have insufficient resistance to deformation under high water head and high dynamic water pressure, and are prone to local deformation or overall instability, and water seepage is likely to occur at the joints.
In the sheet pile cofferdam, a second cross tie rod is added. The second cross tie rod is set inside the first and second pile foundations to disperse and transmit external forces, thereby enhancing the stability and bearing capacity of the cofferdam structure. A filter assembly is set between the pile foundations for filtration, drainage, water stoppage and support.
It enhances the stability and bearing capacity of the cofferdam structure, reduces seepage, optimizes the width of the double-row pile foundation, saves investment, and improves its applicability in complex environments.
Smart Images
Figure CN121827351A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of water conservancy and hydropower engineering construction diversion, in particular to a cofferdam structure and a cofferdam construction method. BACKGROUND
[0002] The cofferdam refers to a temporary enclosure structure built for the construction of permanent water conservancy facilities in water conservancy construction. Its function is to prevent water and soil from entering the construction site of the building, so as to drain water in the cofferdam, excavate the foundation pit, and build the building.
[0003] In water conservancy and hydropower engineering, steel sheet pile cofferdams are widely used in various engineering fields such as pump gates, revetments, reservoir hub buildings, flood control and rescue, etc. due to their advantages of fast construction speed, high structural strength, small occupation of riverbed section, reusability, strong adaptability, environmental protection, etc., creating a dry working environment for building construction.
[0004] In the prior art, the steel sheet pile cofferdam is usually provided with one to two pull rods above the water surface to meet the stability of the cofferdam. However, under high water head and high dynamic water pressure, when the cantilever height of the steel sheet pile below the water surface is large, the traditional steel sheet pile cofferdam structure obviously has insufficient anti-deformation ability, is prone to local deformation or overall instability, and even seepage occurs at the joint. SUMMARY
[0005] The present application provides a cofferdam structure and a cofferdam construction method to solve the problem of insufficient anti-deformation ability of the cofferdam in the prior art, which is prone to local deformation or overall instability, and even seepage occurs at the joint.
[0006] In a first aspect, the present application provides a cofferdam structure, comprising a first pile foundation, a second pile foundation, a surrounding purlin, a first pull rod and a second pull rod, a plurality of first pile foundations are vertically arranged on the water inlet side along the first direction, the bottom of the first pile foundation is adapted to be inserted into the foundation, a plurality of second pile foundations are vertically arranged on the foundation pit side along the first direction, the bottom of the second pile foundation is adapted to be inserted into the foundation, the surrounding purlin is horizontally arranged on one side of the first pile foundation facing the water inlet and one side facing the foundation pit, a plurality of first pull rods are horizontally connected to the two surrounding purlins, a plurality of second pull rods are arranged between the first pile foundation and the second pile foundation, the second direction is perpendicular to the first direction, and two second pull rods in the second direction are arranged in cross.
[0007] Beneficial effects: The present application is aimed at the steel sheet pile cofferdam bearing high water head and high flow speed double pressure, by adding the cross second pull rod inside the first pile foundation and the second pile foundation, effectively dispersing and transmitting external force, reducing the stress concentration of a single pile foundation, thereby enhancing the stability of the cofferdam structure, improving the bearing capacity and anti-seepage performance; at the same time, the width of the double-row pile foundation cofferdam can be optimized, the investment can be saved, the layout space of the cofferdam structure can be reduced, the flow capacity of the cofferdam in the river when arranged in a narrow space can be increased, and the applicability of the cofferdam in complex environment can be improved.
[0008] In an alternative embodiment, the first pull rod and the second pull rod are arranged correspondingly in the second direction.
[0009] Beneficial effects: In the present application, the first pull rod and the second pull rod have the same number of rows in the first direction and correspond in the second direction, so that the first pull rod and the second pull rod are uniformly stressed, thereby enhancing the stability of the cofferdam structure and improving the carrying capacity.
[0010] In an alternative embodiment, the second pull rod is located below the first pull rod in the second direction.
[0011] In an alternative embodiment, the first pile foundation and the second pile foundation are provided with a ring buckle, and the bottom of the second pull rod is connected with the ring buckle.
[0012] In an alternative embodiment, the cofferdam structure further comprises a filter assembly arranged between the first pile foundation and the second pile foundation.
[0013] Beneficial effects: The filter assembly of the present application can play the roles of filtering, draining, water stopping and supporting, thereby ensuring the stability of the cofferdam structure.
[0014] In an alternative embodiment, the filter assembly comprises a water-blocking layer arranged on the side opposite to the first pile foundation and the second pile foundation, and a filter layer arranged on the side opposite to the water-blocking layer and on the top of the foundation.
[0015] Beneficial effects: In the present application, the water-blocking layer mainly plays the roles of filtering, draining, water stopping and supporting, and the filter layer mainly plays the roles of preventing seepage damage and protecting the cofferdam structure.
[0016] In an alternative embodiment, the filter assembly further comprises a filling layer arranged inside the filter layer.
[0017] Beneficial effects: In the present application, the filling layer is backfilled with earth and rock materials and is fully compacted, which can effectively reduce the water permeability of the cofferdam body and the foundation and reduce the amount of seepage water.
[0018] In an alternative embodiment, the first pull rod is arranged in at least one row in the second direction.
[0019] In an alternative embodiment, the second pull rod is arranged in at least one row in the second direction.
[0020] In a second aspect, the present application further provides a cofferdam construction method using the cofferdam structure described above, and the construction method comprises: vertically arranging the first pile foundation on the water inlet side along the first direction and vertically arranging the second pile foundation on the foundation pit side along the first direction; installing the coffer ring on the water inlet side of the first pile foundation and the foundation pit side of the second pile foundation; The first pull rod is arranged to connect two side purlins; The second pull rod is arranged to connect the first pile foundation and the second pile foundation, and the second pull rod is arranged to cross in the second direction. BRIEF DESCRIPTION OF DRAWINGS
[0021] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings required to be used in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.
[0022] Figure 1 A front view of a cofferdam structure according to an embodiment of the present application; Figure 2 A Figure 1 A-A sectional view in the middle; Figure 3 A Figure 1 B-B sectional view in the middle; Figure 4 A Figure 1 An enlarged schematic view at A in the middle; Figure 5 A flowchart of a cofferdam construction method according to an embodiment of the present application.
[0023] Explanation of reference signs: 1, first pile foundation; 2, second pile foundation; 3, purlin; 4, first pull rod; 5, second pull rod; 6, ring buckle; 7, filter assembly; 701, water-blocking layer; 702, filter layer; 8, foundation. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.
[0025] The embodiments of the present application will be described below in combination with Figures 1 to 5 The embodiments of the present application will be described below in combination with
[0026] According to the embodiments of the present application, on the one hand, as Figures 1 to 4As shown, a cofferdam structure is provided, comprising a first pile foundation 1, a second pile foundation 2, a surrounding purlin 3, a first pull rod 4 and a second pull rod 5, a plurality of first pile foundations 1 are vertically arranged along a first direction at the water inlet side, the bottom of the first pile foundation 1 is adapted to be inserted into the foundation 8, a plurality of second pile foundations 2 are vertically arranged along the first direction at the foundation pit side, the bottom of the second pile foundation 2 is adapted to be inserted into the foundation 8, the surrounding purlin 3 is horizontally arranged at the side of the first pile foundation 1 facing the water inlet and the side facing the foundation pit respectively, a plurality of first pull rods 4 are horizontally connected to the two surrounding purlins 3, a plurality of second pull rods 5 are arranged between the first pile foundation 1 and the second pile foundation 2, the second direction is perpendicular to the first direction, and two second pull rods 5 in the second direction are arranged in cross.
[0027] Specifically, the first pile foundation 1 and the second pile foundation 2 in the embodiment are not specifically limited, for example, the first pile foundation 1 and the second pile foundation 2 in the embodiment adopt steel sheet piles, and in other embodiments, the first pile foundation 1 and the second pile foundation 2 can also adopt wooden piles and the like. The adjacent first pile foundation 1 and the adjacent second pile foundation 2 are tightly connected through the S-shaped lock on both sides of the steel sheet pile.
[0028] In the embodiment, the first direction is the Y direction, the second direction is the Z direction, and the third direction is the X direction, and the first direction, the second direction and the third direction are perpendicular to each other.
[0029] In the embodiment, the first direction is perpendicular to the water inlet direction, the first pile foundation 1 and the second pile foundation 2 are vertically arranged along the first direction, and the bottom thereof is inserted into the soil layer of the foundation 8, the spacing of the first pile foundation 1 and the second pile foundation 2 in the X direction is obtained through cofferdam stability calculation. The side of the first pile foundation 1 away from the second pile foundation 2 is the water inlet side, and the side of the second pile foundation 2 away from the first pile foundation 1 is the foundation pit side.
[0030] In the embodiment, the water inlet side of the first pile foundation 1 and the foundation pit side of the second pile foundation 2 are both provided with a surrounding purlin 3 arranged along the first direction, the first pull rod 4 is horizontally arranged along the third direction, and the two ends of the first pull rod 4 are respectively connected to the surrounding purlins 3 on both sides. The surrounding purlin 3 plays a role of fixing the first pull rod 4 and transmitting the load. The second pull rod 5 is arranged along the third direction, and the two ends thereof are respectively connected to the first pile foundation 1 and the second pile foundation 2, and two second pull rods 5 in the second direction are arranged in cross.
[0031] The present application is directed to a steel sheet pile cofferdam bearing high water head and high flow rate double pressure, by adding a cross second pull rod 5 inside the first pile foundation 1 and the second pile foundation 2, effectively dispersing and transmitting external force, reducing the stress concentration of a single pile foundation, thereby enhancing the stability of the cofferdam structure, improving the bearing capacity and anti-permeability; at the same time, the width of the double-row pile foundation cofferdam can be optimized, the investment can be saved, the layout space of the cofferdam structure can be reduced, the flow capacity of the river cofferdam arranged in a narrow space can be increased, and the applicability of the cofferdam in complex environment can be improved.
[0032] In one embodiment, asFigures 1 to 3 As shown, the first pull rods 4 and the second pull rods 5 are arranged correspondingly in the second direction.
[0033] Specifically, in the embodiment, the first pull rods 4 and the second pull rods 5 are arranged in the same number of rows in the first direction, and each group of the first pull rods 4 and the second pull rods 5 are arranged correspondingly in the second direction.
[0034] In the embodiment, the first pull rods 4 and the second pull rods 5 are arranged in the same number of rows in the first direction and correspondingly in the second direction, so that the first pull rods 4 and the second pull rods 5 are uniformly stressed, thereby enhancing the stability of the cofferdam structure and improving the bearing capacity.
[0035] In one embodiment, as shown in the drawings, Figure 1 In the second direction, the second pull rods 5 are arranged below the first pull rods 4.
[0036] Specifically, in the embodiment, the cofferdam purlin 3 and the first pull rod 4 are arranged near the top of the first pile foundation 1 and the second pile foundation 2, the first pull rod 4 plays a role of folding the first pile foundation 1 and the second pile foundation 2, and the second pull rod 5 is arranged below the first pull rod 4, which can effectively disperse and transfer external force, reduce stress concentration of a single pile foundation, thereby enhancing the stability of the cofferdam structure and improving the bearing capacity.
[0037] In one embodiment, as shown in the drawings, Figure 1 The first pile foundation 1 and the second pile foundation 2 are provided with a ring buckle 6, and the bottom of the second pull rod 5 is connected with the ring buckle 6.
[0038] Specifically, in the embodiment, the ring buckle 6 is arranged at the middle position of the first pile foundation 1 and the first pile foundation 1, one end of one of the second pull rods 5 is fixedly connected with the ring buckle 6 on the first pile foundation 1, and the other end is welded with the second pile foundation 2, one end of the other second pull rod 5 is fixedly connected with the ring buckle 6 on the second pile foundation 2, and the other end is welded with the first pile foundation 1, and the end of the second pull rod 5 connected with the ring buckle 6 is lower than the end connected with the first pile foundation 1 and the first pile foundation 1, so that the second pull rod 5 is arranged obliquely between the first pile foundation 1 and the first pile foundation 1.
[0039] In one embodiment, as shown in the drawings, Figure 1 The cofferdam structure further comprises a filter assembly 7, and the filter assembly 7 is arranged between the first pile foundation 1 and the second pile foundation 2.
[0040] The filter assembly 7 can play the roles of filtering, draining, water stopping and supporting, and ensures the stability of the cofferdam structure.
[0041] In one embodiment, as shown in the drawings, Figure 1 and Figure 4As shown, the filter assembly 7 comprises a water-blocking layer 701 and a filter layer 702, the water-blocking layer 701 is arranged on the side opposite to the first pile foundation 1 and the second pile foundation 2, and the filter layer 702 is arranged on the side opposite to the water-blocking layer 701 and the top of the foundation 8.
[0042] Specifically, the water-blocking layer 701 in the embodiment is not limited, for example, the water-blocking layer 701 in the embodiment adopts a water-blocking structure of bamboo curtain piece. The filter layer 702 in the embodiment is not limited, for example, the filter layer 702 in the embodiment adopts a U-shaped anti-filtration geotextile. One layer of water-blocking layer 701 is arranged on the side opposite to the first pile foundation 1 and the second pile foundation 2, which mainly plays a filtering, drainage, water-stopping and supporting role; one layer of second isolation layer is arranged between the two sides of the water-blocking layer 701 and the soil layer of the foundation 8, which mainly plays a role of preventing penetration damage and protecting the cofferdam structure.
[0043] The water-blocking layer 701 in the embodiment mainly plays a filtering, drainage, water-stopping and supporting role, and the filter layer 702 mainly plays a role of preventing penetration damage and protecting the cofferdam structure.
[0044] In one embodiment, the filter assembly 7 further comprises a filling layer, and the filling layer is arranged inside the filter layer 702.
[0045] Specifically, the filling layer in the embodiment is not limited, for example, the filling layer in the embodiment adopts earth and stone materials. After the earth and stone materials are filled inside the U-shaped anti-filtration geotextile, the cofferdam structure is formed.
[0046] The filling layer in the embodiment adopts earth and stone materials for backfilling, and after being fully compacted, the water permeability of the cofferdam body and the foundation 8 can be effectively reduced, and the amount of seepage water can be reduced.
[0047] In one embodiment, as shown in the drawings, Figure 1 The first pull rod 4 is arranged at least in one row in the second direction.
[0048] In one embodiment, as shown in the drawings, Figure 1 The second pull rod 5 is arranged at least in one row in the second direction.
[0049] Specifically, the first pull rod 4 and the second pull rod 5 in the embodiment are arranged at least in two rows, the first row of first pull rods 4 is arranged in the Y direction and spaced apart through the front and rear rows of cofferdam purlins 3, which is consistent with the traditional arrangement; the second row of pull rods is improved, and the second row of pull rods is arranged in the Z direction and spaced apart in the Y direction inside the front and rear rows of steel sheet piles.
[0050] According to the embodiment of the present application, on the other hand, as shown in the drawings, Figure 5 A cofferdam construction method is also provided, which adopts the cofferdam structure described above, and the construction method comprises: The first pile foundation 1 is vertically arranged along the first direction at the water inlet side, and the second pile foundation 2 is vertically arranged along the first direction at the foundation pit side. The coaming 3 is installed at the water inlet side of the first pile foundation 1 and the foundation pit side of the second pile foundation 2. The first pull rod 4 is installed to connect the two coamings 3. The second pull rod 5 is installed to connect the first pile foundation 1 and the second pile foundation 2, and the second pull rod 5 is arranged in the second direction.
[0051] Specifically, in the construction of the embodiment, the first pile foundation 1 is vertically arranged along the first direction in the soil layer of the foundation 8, and the specific distance between the first pile foundation 1 and the second pile foundation 2 in the third direction needs to be determined according to the cofferdam stability and seepage calculation. The water-blocking layer 701 is arranged inside the first pile foundation 1 and the second pile foundation 2, mainly for filtering, draining, water stopping and supporting. The filter layer 702 is arranged between the water-blocking layers 701 on both sides and the soil layer of the foundation 8, mainly for preventing seepage damage and protecting the cofferdam structure. The filter layer 702 is filled with a filling layer to form a cofferdam structure.
[0052] In order to improve the overall strength of the cofferdam structure, the coaming 3 is arranged outside the first pile foundation 1 and the second pile foundation 2. In order to facilitate construction, the height of the coaming 3 in the first direction needs to be higher than the water retaining level of the cofferdam design standard on the water inlet side. The coaming 3 is arranged horizontally along the first direction. The first pile foundation 1 and the second pile foundation 2 form a whole through the first pull rod 4 and the coaming 3. The first pull rod 4 is arranged in the second direction and can be greater than or equal to one in the horizontal direction. The spacing L in the first direction can be obtained by calculation. In view of the fact that the cofferdam cantilever above the present mud surface is high, it is difficult to meet the overall stability of the cofferdam structure by arranging the first pull rod 4 only at the water retaining level of the cofferdam design standard. The second pull rod 5 is additionally arranged between the first pile foundation 1 and the second pile foundation 2. The second pull rod 5 is arranged in the second direction and is arranged in the first direction. The lower part of the second pull rod 5 is connected with the ring buckle 6 on the first pile foundation 1, and the upper part is welded with the second pile foundation 2. Similarly, the lower part of the second pull rod 5 is connected with the ring buckle 6 on the second pile foundation 2, and the upper part is welded with the first pile foundation 1. The welding position and the position of the ring buckle 6 and the length of the second pull rod 5 need to be obtained according to the cofferdam stability calculation. The spacing L of the second pull rod 5 in the first direction is the same as that of the first pull rod 4. The ring buckle 6 is welded with the first pile foundation 1 and the second pile foundation 2 before the first pile foundation 1 and the second pile foundation 2 are installed, forming a whole.
[0053] The present application is directed to the steel sheet pile cofferdam which bears the high water head and high flow velocity double pressure, through the second cross rod 5 which is additionally arranged in the first pile foundation 1 and the second pile foundation 2, the external force is effectively dispersed and transmitted, the stress concentration of the single pile foundation is reduced, thereby the cofferdam structure stability is enhanced, the bearing capacity and the anti-permeability are improved; meanwhile, the width of the double-row pile foundation cofferdam can be optimized, the investment is saved; the arrangement space of the cofferdam structure is reduced, the flow capacity when the river cofferdam is arranged in the narrow space is increased, and the applicable performance of the cofferdam in the complex environment is improved.
[0054] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.
Claims
1. A cofferdam structure, characterized in that, include: First pile foundation (1), a plurality of first pile foundations (1) are vertically arranged along a first direction on the water inlet side, and the bottom of the first pile foundation (1) is adapted to be inserted into the foundation (8); Second pile foundation (2), several second pile foundations (2) are vertically arranged on the side of the foundation pit along the first direction, and the bottom of the second pile foundation (2) is adapted to be inserted into the foundation (8); Waler (3), the waler (3) is horizontally set on the side of the first pile foundation (1) facing the water inlet and the side facing the foundation pit respectively; First tie rod (4), several first tie rods (4) are horizontally connected to the walers (3) on both sides; Second tie rod (5), several second tie rods (5) are arranged between the first pile foundation (1) and the second pile foundation (2), the second direction is perpendicular to the first direction, and the two second tie rods (5) in the second direction are arranged crosswise.
2. The cofferdam structure according to claim 1, characterized in that, The first pull rod (4) and the second pull rod (5) are respectively arranged in the second direction.
3. The cofferdam structure according to claim 1 or 2, characterized in that, In the second direction, the second pull rod (5) is located below the first pull rod (4).
4. The cofferdam structure according to claim 1, characterized in that, The first pile foundation (1) and the second pile foundation (2) are provided with ring buckles (6), and the bottom of the second tie rod (5) is connected to the ring buckles (6).
5. The cofferdam structure according to claim 1, characterized in that, Also includes: A filter assembly (7) is disposed between the first pile foundation (1) and the second pile foundation (2).
6. The cofferdam structure according to claim 5, characterized in that, The filter assembly (7) includes: A water-blocking layer (701) is provided on the side opposite to the first pile foundation (1) and the second pile foundation (2); A filter layer (702) is disposed on the side of the water-blocking layer (701) opposite to the first pile foundation (1) and the second pile foundation (2) and on the top of the foundation (8).
7. The cofferdam structure according to claim 6, characterized in that, The filter assembly (7) further includes: A filling layer is disposed inside the filter layer (702).
8. The cofferdam structure according to claim 1, characterized in that, The first tie rod (4) is provided at least once in the second direction.
9. The cofferdam structure according to claim 1, characterized in that, The second tie rod (5) is provided at least once in the second direction.
10. A method for constructing a cofferdam, characterized in that, The construction method of the cofferdam structure according to any one of claims 1 to 9 includes: The first pile foundation (1) is vertically installed on the water inlet side along the first direction, and the second pile foundation (2) is vertically installed on the pit side along the first direction; A waler (3) is installed on the water inlet side of the first pile foundation (1) and the pit side of the second pile foundation (2); Install the first tie rod (4) to connect the two side walers (3); Install the second tie rod (5) to connect the first pile foundation (1) and the second pile foundation (2), and the second tie rod (5) is set in a cross direction.