CN219793968U

CN219793968U - Composite cofferdam structure

Info

Publication number: CN219793968U
Application number: CN202321143404.7U
Authority: CN
Inventors: 贺华雄; 柳兵; 王晓雄; 李振华; 陈冲; 马伟; 李军辉; 闫永辉; 李艳庆; 杨青; 冯雪峰
Original assignee: Sinohydro Engineering Bureau 4 Co Ltd
Current assignee: Sinohydro Engineering Bureau 4 Co Ltd
Priority date: 2023-05-12
Filing date: 2023-05-12
Publication date: 2023-10-03
Anticipated expiration: 2033-05-12

Abstract

The utility model relates to the field of water conservancy construction, and discloses a composite cofferdam structure, which comprises a matrix surrounding a foundation pit isolated river bed, wherein an impervious wall is arranged inside the matrix from top to bottom; the top of the base body is provided with an upper component, the upper component comprises a concrete cover, a steel member and geotechnical cloth, and the concrete cover is arranged on the top of the base body and is positioned on the water facing side of the impervious wall; the steel member is arranged at the water facing end of the concrete cover; and the steel member and the concrete cover below the steel member are covered with the geotextile. The utility model comprises a matrix and an impervious wall of a lower earth-rock cofferdam which can be rapidly constructed, so that the foundation pit surrounded by the cofferdam is provided with dry construction conditions, and a concrete foundation cover, a steel member structure and a geotechnical cloth combined structure are arranged at the upper part of the earth-rock cofferdam in the later stage to form a composite cofferdam structure.

Description

Composite cofferdam structure

Technical Field

The utility model relates to the technical field of water conservancy buildings, in particular to a composite cofferdam structure.

Background

The hydraulic construction engineering has large flow rate of flood peaks and large flow amplitude in the dead period according to different hydraulic environment construction conditions, and is suitable for construction in the dead period by fully utilizing the dead water period. For the channel junction engineering, the leading channel and the ship lock engineering are arranged near the shore, cofferdam water retaining is adopted during construction diversion, dry construction conditions are formed, and then the hydraulic building in the foundation pit is constructed.

The cofferdam arranged on a narrow riverbed or a mountain riverway is limited by the topography and geological conditions, and when the water retaining head is higher, the prior art adopts a conventional earth-rock cofferdam or a conventional concrete cofferdam, so that the following defects exist:

1. when the earth-rock cofferdam is adopted: (1) The dam has larger body type, larger section, larger dam filling and seepage-proofing engineering amount, longer cofferdam engineering construction time and difficult rapid main engineering (in foundation pit) construction; (2) Because the cofferdam greatly bundles narrow river channels, the flow cross section is reduced, the flow guiding difficulty is increased, the flow guiding building is difficult to arrange, and the flood risk is increased.

2. When the concrete cofferdam is adopted: (1) The construction cost of cofferdam engineering is high, the investment is large, and the cofferdam engineering is uneconomical; (2) The sub cofferdam is firstly constructed, and then the concrete cofferdam is constructed under the protection of the sub cofferdam, so that the time from the construction of the cofferdam and accessories to normal water retaining is long, and the construction period is not facilitated; and (3) the later dismantling difficulty is high.

Disclosure of Invention

In order to overcome one or more of the technical problems, the utility model aims to provide a composite cofferdam structure which comprises a lower earth-rock cofferdam structure, an upper concrete foundation, a steel structure and geotechnical cloth, and has the advantages of simple structure, good water retaining performance and small construction difficulty.

The utility model provides the following technical scheme:

a composite cofferdam structure comprising a matrix (200) surrounding an insulated riverbed of a foundation pit, characterized in that: an impermeable wall (201) is arranged in the base body (200) from top to bottom; the top of the base body (200) is provided with an upper component (100), the upper component (100) comprises a concrete cover (101), a steel member (102) and geotechnical cloth (103), and the concrete cover (101) is arranged at the top of the base body (200) and is positioned on the water facing side of the impervious wall (201); the steel member (102) is arranged at the water facing end of the concrete cover (101); the geotextile (103) is covered on the steel member (102) and the concrete cover (101) below the steel member (102).

According to the embodiment, the water retaining cofferdam is formed by combining the matrix, the concrete cover, the steel member and the geotechnical cloth, the matrix is smaller than the common cofferdam, the steel member on the upper part is convenient and rapid to construct, the water retaining effect of the combined geotechnical cloth is better, and the construction period of the cofferdam can be greatly shortened. And because the cofferdam structure is small in size, a narrow river channel is not required to be bound greatly, the diversion effect is good, and the flood risk is also small.

Preferably, the steel member (102) is provided with a stopper (104) pressing the geotextile (103) on a side facing the back water.

Preferably, the stop (104) is selected from the group consisting of bagged earth and stones.

Preferably, the type of barrier (201) is selected from high pressure rotary spray barriers.

Preferably, one end of the geotextile (103) is fixed in the concrete cover (101), the other end spans over the steel member (102) and the concrete cover (101) on the leeward side below the steel member (102), and the length of the geotextile leaves a margin towards the leeward side.

Preferably, stones (202) are laid on the slope of the water facing side of the base body (200).

Preferably, the stone block (202) has a size of at least 0.5m.

Preferably, the concrete cover (102) is provided with construction joints at certain intervals along the length direction of the cofferdam, and water is stopped in the construction joints.

Preferably, the construction joint is spaced by 15-20 m.

Preferably, the top of the base body (200) and the leeward side of the steel member (102) are available for traffic.

Compared with the prior art, the utility model has the following beneficial effects:

the utility model comprises a matrix and a impervious wall which can rapidly construct the lower earth-rock cofferdam, so that the foundation pit surrounded by the cofferdam is provided with dry construction conditions, and a concrete cover, a steel member and geotechnical cloth combined structure is arranged at the upper part of the earth-rock cofferdam in the later stage to form a composite cofferdam structure.

According to the water situation forecasting condition, the arrangement of bagged earth and stones at the steel member can be adjusted, and the main engineering construction in the foundation pit can be quickly carried out on the premise of guaranteeing the stability and safety of the composite cofferdam structure, so that the progress of a key line is accelerated, and the overall benefit of the engineering is better improved.

Drawings

Fig. 1 is a schematic plan layout view of a composite cofferdam structure according to a first embodiment of the present utility model.

Fig. 2 is a schematic longitudinal section view of a composite cofferdam structure according to a first embodiment of the present utility model.

The reference numerals in the drawings are:

100. an upper assembly; 101. a concrete cover; 102. a steel member; 103. geotextile; 104. a blocking member; 200. a base; 201. a seepage-proof wall; 202. and (5) stone blocks.

Detailed Description

The present utility model will be described in detail with reference to the following examples and drawings, but it should be understood that the examples and drawings are only for illustrative purposes and are not intended to limit the scope of the present utility model in any way. All reasonable variations and combinations that are included within the scope of the inventive concept fall within the scope of the present utility model.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "rear", etc., are based on those shown in the drawings, are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or elements referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present utility model; the terms "first," "second," "third," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance, and further, unless otherwise expressly specified and defined, the terms "disposed," "mounted," "connected," "coupled," and the like are to be construed broadly, and may be either fixedly coupled, detachably coupled, or integrally coupled, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The utility model is further described below with reference to the accompanying drawings.

Example 1

The lower part of the composite cofferdam structure is in a structure of a earth-rock cofferdam construction matrix 200 as shown in fig. 1, and the upper part of the composite cofferdam structure is in a structure of an upper assembly 100 for retaining water, and as shown in fig. 2, the upper assembly 100 comprises a concrete cover 101, a steel member 102 and geotechnical cloth 103. On the one hand, when the river channel inflow is smaller, the matrix 200 structure of the lower earth-rock cofferdam can be quickly constructed, the matrix 200 is smaller in size, the construction period is short, and the composite cofferdam structure is less influenced by the river channel inflow; on the other hand, the river channel flow section is less in occupied pressure, the river channel flow capacity is enhanced, and the flow guiding difficulty and flood risk in the construction period can be reduced; when the water condition forecast upstream exceeds standard flood, filling bagged earth and stones on the side of the steel structure, close to the foundation pit, of the steel structure, forming a stable upper combined structure, and jointly retaining water with the earth and stone cofferdam matrix.

As shown in fig. 2, the lower part of the composite cofferdam structure comprises a matrix 200 surrounding a foundation pit and isolating a river bed, wherein the longitudinal section of the matrix 200 is trapezoidal, the left side of the matrix 200 is a water facing surface, the right side of the matrix is a water facing surface, and the top height of the matrix 200 is designed to be higher than the highest water level line. Inside the matrix 200, a cut-off wall 201 is arranged from the top of the matrix 200 to the position below the river bed surface, the matrix 200 can be constructed by sand gravel, a stone 202 is arranged on the water-facing slope surface of the matrix 200 to protect the slope, and the stone 202 is preferably selected from large stones to form a large stone slope. A concrete cover 101 is arranged at the top of the base 200 in front of the impervious wall 201, the concrete cover 101 is used as a foundation of the upper steel member 102, and is connected with the upper steel member 102 and the lower earth-rock cofferdam to jointly retain water; a steel member 102 is arranged at one end of the concrete cover 101 facing the water along the cofferdam structure, and geotextiles 103 are paved on the outer surface of the steel member 102 and the concrete cover 101 facing the back water side; if the water level rises, a baffle 104 can be additionally arranged on the geotechnical cloth 103 to compress the steel member 102 so as to improve the water retaining capacity of the steel member 102, the baffle 104 can be made of bagged earth and stones, and the geotechnical cloth 103 has the function of blocking river bed water so as to prevent river water from overflowing the cofferdam; the steel member 102 is designed to withstand the water pressure from the overlying geotextile 103, with its back side supported by the barrier 104, and the top of the base 200 is available for pedestrian and vehicular traffic on the back side of the steel member 102.

After the river is shut off, firstly building a matrix 200 of the earth-rock cofferdam outside the foundation pit and arranging a longitudinal impervious wall 201 in the matrix 200, wherein the type of the impervious wall 201 can be selected from high-pressure jet grouting impervious walls, and the high-pressure jet grouting impervious walls are underground continuous walls which are built by mixing cement paste and stirred gravel soil particles in holes drilled in the matrix by utilizing a high-pressure jet technology, and solidifying and hardening. Filling the top of the substrate 200 to a design elevation; and then, according to engineering construction and river channel overflow requirements in a dead period, a combined structure of a concrete cover 101, a steel member 102, geotechnical cloth 103 and a baffle 104 is additionally arranged on the upper part of a base 200 of the built earth-rock cofferdam so as to heighten a composite cofferdam structure and improve the overflow capacity of an overflow channel. The concrete cover 101 is arranged on the upper part of the cofferdam matrix 200, the steel member 102 is built on the concrete cover 101, one end of the geotextile 103 is positioned on the upstream side of the steel member 102 and is fixed by the concrete cover 101, and the other end extends towards the back water side to cover the steel member 102 and the concrete cover 101 on the back water side; in order to avoid the damage of the concrete cover 101 caused by the uneven sedimentation of the cofferdam structure, a construction joint is arranged on the concrete cover 101 along the cofferdam structure at intervals of 15-20 m, and water is arranged between the joints.

In combination with water condition forecasting analysis, when meeting the super-standard flood, the machine selects to backfill bagged earth and stones on the side of the steel member 102 facing the foundation pit so as to ensure that the combined structure is stable and jointly blocks water and flood with the lower earth and stone cofferdam.

The construction method of the composite cofferdam structure provided by the embodiment comprises the following steps:

1) And a soil-rock cofferdam is arranged outside the foundation pit, the upper and the lower stream of the cofferdam are respectively connected with a bank slope road or a hydraulic building, and a concrete cover 101 and a high-pressure jet grouting impervious wall are arranged at the connection part to form a closed impervious system.

2) And rapidly constructing the matrix 200 of the earth-rock cofferdam, the large-block stone revetment and the high-pressure jet grouting impervious wall to form dry construction conditions.

3) A concrete cover 101 is arranged on the upper part of a matrix 200 of the earth-rock cofferdam, and is lapped with a parallel impervious wall 201 to serve as a steel member foundation.

4) One end of the geotextile 103 is buried in the concrete cover 101, and the buried length is not less than 0.5m; the other end spans over the steel member 102 and is arranged on the concrete cover 101 of the cofferdam, and the length of the cofferdam leaves a margin towards one side of the back surface; and the joint lap joint is made at the construction joint.

5) In order to ensure the stability of the upper combined structure of the earth-rock cofferdam, before flood comes, stacking bagged earth-rock on the side of the steel member 102 facing the foundation pit; after flood is eliminated, the bagged earth and stones are transported away, and the traffic of the weir crest is restored. The bagged soil and stones are stacked nearby and can be reused.

6) After the construction diversion task is completed, the composite cofferdam structure is dismantled to meet the requirements of flood operation, navigation and the like in the operation period.

Example two

Reservoir total volume of certain aviation armature button engineering 1.61 hundred million m ³ The installed capacity of the power station is 48MW, and the navigation building is designed according to the IV level of the inland river, and the channel level is IV level. The engineering grade is II, the engineering scale is large (2), the grade of the main building is 2, and the grade of the secondary building is 3. The total construction period of the engineering construction is 55 months.

The main building of the junction comprises a sluice gate, a factory building, a ship lock and two-bank joint dam sections, wherein the building is provided with a left-bank Han river flood control dike heightening reconstruction section, a left-bank storage gate groove dam section, a sluice gate dam section (18 holes in total and 313.00m long), a riverbed factory building dam section, a lock head dam section on the ship lock and a right-bank joint dam section from left to right along the axis of the dam.

The earth-rock cofferdam in the dead period is a 5-level building, the water retaining period is 11 months to 4 months next year, the flood standard adopts a 5-year reproduction period, and the flow Q=563 m ³ And/s (P=20%), the design water level of the upstream section of the withered earth-rock cofferdam is 241.12m, and the height of the cofferdam top is 242.00m. The upper and lower ends of the dead period earth-rock cofferdam are respectively connected with the right bank slope road and the hydraulic building. The width of the weir top of the cofferdam is 8m, the slope ratios of the upstream surface side slope and the back surface side slope are 1:2 and 1:1.8 respectively, the weir body adopts impermeable soil materials preferentially, and the rest part adopts stone residues; the upstream face is provided with a 0.5m thick large stone.

Firstly, constructing a lower earth-rock cofferdam weir body, a large rock slope protection and a impervious wall, and rapidly forming a first-stage foundation pit of a right bank factory building; and then, arranging a combined structure of the concrete cover 101, the steel member 102 and the geotechnical cloth 103 on the upper part of the matrix 200 of the earth-rock cofferdam to form a composite cofferdam structure and retain water. After that, the foundation pit main engineering construction is carried out rapidly, and when the flood is designed in an out-of-standard mode before the second year, the composite cofferdam structure successfully withstands the flood.

The above examples are only preferred embodiments of the present utility model, and the scope of the present utility model is not limited to the above examples. All technical schemes belonging to the concept of the utility model belong to the protection scope of the utility model. It should be noted that modifications and adaptations to the present utility model may occur to one skilled in the art without departing from the principles of the present utility model and are intended to be within the scope of the present utility model.

Claims

1. A composite cofferdam structure comprising a matrix (200) surrounding an insulated riverbed of a foundation pit, characterized in that: an impermeable wall (201) is arranged in the base body (200) from top to bottom; the top of the base body (200) is provided with an upper component (100), the upper component (100) comprises a concrete cover (101), a steel member (102) and geotechnical cloth (103), and the concrete cover (101) is arranged at the top of the base body (200) and is positioned on the water facing side of the impervious wall (201); the steel member (102) is arranged at the water facing end of the concrete cover (101); the steel member (102) and the concrete cover (101) below the steel member (102) are covered with geotextiles (103).

2. The composite cofferdam structure of claim 1, wherein: the steel member (102) is provided with a stopper (104) on the side facing the back water, which presses the geotextile (103).

3. The composite cofferdam structure of claim 2, wherein: the baffle (104) is selected from bagged earth and stones.

4. The composite cofferdam structure of claim 1, wherein: the type of the impervious wall (201) is selected from high-pressure rotary spraying impervious walls.

5. The composite cofferdam structure of claim 1, wherein: one end of the geotextile (103) is fixed in the concrete cover (101), the other end of the geotextile spans the steel member (102) and the concrete cover (101) on the water-carrying side below the steel member (102), and the length of the geotextile leaves a margin towards the water-carrying side.

6. The composite cofferdam structure of claim 1, wherein: and a stone block (202) is paved on the slope surface of the water facing side of the base body (200).

7. The composite cofferdam structure of claim 6, wherein: the stone block (202) has a size of at least 0.5m.

8. The composite cofferdam structure of claim 1, wherein: the concrete cover (101) is provided with construction joints at certain intervals along the length direction of the cofferdam, and water is stopped in the construction joints.

9. The composite cofferdam structure of claim 8, wherein: the distance between the construction joints is 15-20 m.

10. A composite cofferdam structure as claimed in any one of claims 1 to 9, wherein: the top of the base body (200) and the leeward side of the steel member (102) can be used for traffic.