CN212248304U

CN212248304U - Flow-guiding cofferdam for urban comprehensive pipe gallery passing through wider water-passing river channel

Info

Publication number: CN212248304U
Application number: CN202021138121.XU
Authority: CN
Inventors: 姚会超; 荣太龙; 梁洪涛
Original assignee: China 22MCC Group Corp Ltd
Current assignee: China 22MCC Group Corp Ltd
Priority date: 2020-06-18
Filing date: 2020-06-18
Publication date: 2020-12-29
Anticipated expiration: 2030-06-18

Abstract

The utility model provides a flow-guiding cofferdam for a wider water-passing river channel passing under an urban comprehensive pipe gallery, which comprises an earth cofferdam around a foundation pit, wherein the earth cofferdam is provided with row piles made of steel plates, secondary ribs are fixedly connected at the back of the row piles, the row piles are arranged in a straight line along the upper opening of the earth cofferdam, and the splicing seams of adjacent row piles are provided with connecting structures; the lower part of each row pile extends into the earth cofferdam, the rear side of each row pile is provided with an inclined strut, the inclined strut is inclined by 45 degrees, the lower end of the inclined strut is inserted into the earth cofferdam, and the upper end of the inclined strut is fixedly connected with a transverse main rib; main rib and secondary rib rigid coupling, this scheme effectively resists rivers and to the erodeing of cofferdam lateral wall, and the steadiness is good, prevents that rivers from permeating water to the foundation ditch infiltration along loose soil property, and the cost is lower than the stone cofferdam.

Description

Flow-guiding cofferdam for urban comprehensive pipe gallery passing through wider water-passing river channel

Technical Field

The utility model belongs to pass through river course piping lane construction technology, concretely relates to city utility tunnel passes broad river course's water conservancy diversion cofferdam down.

Background

The urban comprehensive pipe gallery is generally built in a new urban area and is located at a suburb joint part, villages, farmlands, riverways and the like in the villages are distributed more frequently, and geographic conditions are complex. In the difficult technical problem of work progress, the piping lane construction in the water channel of crossing belongs to the great one of the degree of difficulty. Because when crossing water river course construction, need carry out the water conservancy diversion to rivers, just can carry out the foundation ditch excavation. For a foundation pit excavated in a wider river channel, construction is usually performed by adopting a segmented cofferdam and segmented backflow method.

The cofferdam generally adopts earth-rock cofferdams to flow backwards more, and the construction of the earth-rock cofferdam has certain limitation. The common earth cofferdam is only suitable for shallow water with slow flow rate and the bottom of the cofferdam is a waterproof soil layer. The earth-rock cofferdam is greatly limited by requirements of stone producing areas, transportation conditions, labor cost and construction period. Generally, the cofferdam is mainly used for the non-overflow cofferdam, the water level is not greatly increased in the flood season, and temporary heightening and reinforcement are not needed.

Under the conditions that the water depth is greater than 1 meter in the non-flood season, the flow velocity is greater than 1 meter/s, the water seepage of riverbed soil is large, the content of cohesive soil is small, the sand content is large, the water level in the flood season increases irregularly, the advance judgment cannot be carried out, the follow-up remediation construction has great difficulty and the like, the limitation of the common earth-rock cofferdam is obviously embodied, and the potential safety hazard of water overflow exists.

SUMMERY OF THE UTILITY MODEL

The to-be-solved problem of the utility model is that the construction of enclosing the weir in the river course receives factor influences such as soil property osmotic coefficient is big, the velocity of water is very fast, flood season water level lifting does not have obvious law, leads to appearing the infiltration, collapse, crosses the defect of phenomenons such as water.

For solving the above-mentioned potential safety hazard, the utility model provides a technical scheme is:

a diversion cofferdam for a wider overflow river channel passing under an urban comprehensive pipe gallery comprises an earth cofferdam at the periphery of a foundation pit, row piles made of steel plates are arranged on the earth cofferdam, secondary ribs are fixedly connected to the back of the row piles, the row piles are arranged in a straight line along the upper opening of the earth cofferdam, and a connecting structure is arranged at a splicing seam of adjacent row piles; the lower part of each row pile extends into the earth cofferdam, the rear side of each row pile is provided with an inclined strut, the inclined strut is inclined by 45 degrees, the lower end of the inclined strut is inserted into the earth cofferdam, and the upper end of the inclined strut is fixedly connected with a transverse main rib; the main rib is fixedly connected with the secondary rib.

The utility model provides a cofferdam has following advantage: the method has the advantages that scouring caused by water flow to the side wall of the cofferdam is effectively resisted, and the stability of the cofferdam is improved; secondly, water flow is prevented from permeating along the capillary seams in the loose soil or permeating too fast, and the hidden danger of water seepage and water permeability is avoided; the problem of high cost of stone purchasing, transporting and manual arrangement of the rubble cofferdam is solved, the construction cost is reduced, and the construction period is shortened; the risk of water overflow and backflow caused by sudden rise of the water level in the flood season is solved, and when the water level is raised in the flood season, row piles can be manufactured and continue to be reinforced upwards, so that the construction risk is reduced, and the safety of constructors is guaranteed; after the building construction in the cofferdam is finished, the steel sheet pile can be hoisted after the backfilling is finished, the steel sheet pile can be reused, and the cost is reduced.

Drawings

FIG. 1 is a schematic diagram of a rear side structure of a row pile;

FIG. 2 is a schematic diagram of a row pile cofferdam installation structure;

fig. 3 is the overall installation effect diagram of the present invention.

In the figure: the row pile comprises row piles 1, secondary ribs 2, main ribs 3, inclined struts 4 and an earth cofferdam 5.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1-3, a diversion cofferdam for a wide river course passing through the lower part of an urban comprehensive pipe gallery comprises an earth cofferdam at the periphery of a foundation pit, wherein the upper opening of the earth cofferdam is 4 meters wide, and the lower opening of the earth cofferdam is 8 meters wide.

The utility model designs the row piles made of steel plates on the earth cofferdam, secondary ribs are fixedly connected behind the row piles, the row piles are arranged in a straight line along the upper opening of the earth cofferdam, and the splicing seams of adjacent row piles are provided with connecting structures; the lower part of each row pile extends into the earth cofferdam, the rear side of each row pile is provided with an inclined strut, the inclined strut is inclined by 45 degrees, the lower end of the inclined strut is inserted into the earth cofferdam, and the upper end of the inclined strut is fixedly connected with a transverse main rib; the main rib is fixedly connected with the secondary rib.

The construction method of the diversion cofferdam for the urban comprehensive pipe gallery to pass through the wide river channel is described in detail below with reference to the accompanying drawings 1 to 3 and specific examples:

1) and (3) manufacturing the steel plate row pile 1. 4 steel plates with width, thickness and length of 1000 × 10 × 4000mm are arranged up and down to form a group, and the row piles are formed by welding along the length edge.

2) And vertical secondary ribs 2 are welded on the side surface of each row pile 1 facing the foundation pit at intervals of 1 m. The secondary rib 2 adopts 10# channel steel double-sided girth welding. In order to facilitate the hoisting of the row piles, hoisting rings are welded on the back of the steel plate (the surface on the side of the foundation pit) of the row piles 1.

3) And building an earth cofferdam 5, wherein the upper opening of the earth cofferdam 5 is 4m wide and the lower opening is 8m wide in the example. When in construction, the soil is filled to be 0.5m higher than the water surface, a light rolling machine is used for rolling for 6 times, and the soil is continuously piled and rolled to be 1.3 m higher than the water surface and equal to the height of the original first layer river dam. The construction of the earth cofferdam 5 can be performed simultaneously with the construction of the row piles 1 by arranging construction areas respectively.

4) The diagonal brace 4 is pressed in. In this example, the diagonal brace 4 is made of a 10# channel steel with a length of 4 m. During arrangement, one inclined strut 4 is inserted into the top of the cofferdam at intervals of 1m, the inclined strut 4 inclines by 45 degrees, the lower end of the inclined strut 4 extends towards the side of the foundation pit, and the upper end of the inclined strut is positioned on a vertical plane where the positioning line of the row piles 1 is positioned. The row pile positioning line is a positioning line of the insertion position of the row pile 1 drawn on the surface of the upper opening of the earth cofferdam 5. The positioning line can be drawn on the outer side line of the upper opening, and can also be drawn at the

position

1 or 2 meters away from the outer side line.

5) The transverse main ribs 3 are welded. In order to facilitate the piling of the piles 1, the main ribs 3 are arranged along the extending direction of the cofferdam along the angle change, the main ribs 3 are not too long, and 2m long 10# channel steel can be adopted. When the main rib 3 is arranged, the main rib 3 is arranged at the upper end of the inclined strut 4, the levelness of all the main ribs 3 and the parallelism of the main rib 3 and the positioning line weight surface of the row pile 1 are ensured, and then the welding is firm.

6) And (5) hoisting the steel plate row piles. And integrally hoisting a group of row piles 1, hoisting the row piles to be attached to the outer side of the main rib 3, checking verticality, pressing the row piles into the earth cofferdam, and welding the main rib 3 and the vertical secondary rib 2. In the example, the row piles 1 are pressed into the river bed (namely the platform where the upper opening of the earth cofferdam is located) for 1.2m, and the steel plates are kept vertical in the pile pressing process. When the row pile 1 is driven to the required height, the main rib 3 is welded with the vertical secondary rib 2. The width of the upper opening of the earth cofferdam 5 at the inner side of the row pile 1 is 2-4 m, and the width at the outer side of the row pile 1 is 0-2 m.

7) And connecting and reinforcing the splicing seams of the two adjacent rows of piles. The part of the splicing seam exposed above the earth cofferdam is subjected to waterproof treatment, and waterproof strips can be filled and waterproof materials can be coated. The splicing seam position can also adopt a welding fixation or other structures which can ensure that the two rows of piles can be mutually and fixedly connected.

The utility model provides a cofferdam has following advantage:

(1) effectively resist the erosion that rivers caused the cofferdam lateral wall sooner, promote the steadiness of cofferdam.

(2) Prevent water flow from permeating along the capillary seams in the loose soil or permeating too fast, and avoid the hidden trouble of water seepage and permeation.

(3) The problem of high stone material purchase, transportation, artifical row of rubble cofferdam cost is solved, reduce construction cost, reduction of erection time.

(4) The problem of flood season water level sudden rising arouses the risk of crossing water and flowing backward is solved, and when flood season water level rose, still can make the campshed, continues to consolidate upwards, reduces the construction risk, guarantees constructor safety.

(5) After the construction in the cofferdam is finished, the steel sheet pile can be lifted for reuse after the backfilling is finished. When the lifting steel plate row piles are lifted off the ground, an oblique pulling mode is adopted, and the impact is avoided to close on the pile body.

Claims

1. The utility model provides a pass wide water channel's water conservancy diversion cofferdam under city utility tunnel, includes the peripheral earth cofferdam of foundation ditch, its characterized in that: the soil cofferdam is provided with row piles made of steel plates, the rear side faces of the row piles are fixedly connected with secondary ribs, the row piles are arranged in a line along the upper opening of the soil cofferdam, and a connecting structure is arranged at the splicing seams of adjacent row piles; the lower part of each row pile extends into the earth cofferdam, the rear side of each row pile is provided with an inclined strut, the inclined strut is inclined by 45 degrees, the lower end of the inclined strut is inserted into the earth cofferdam, and the upper end of the inclined strut is fixedly connected with a transverse main rib; the main rib is fixedly connected with the secondary rib.

2. The diversion cofferdam for the urban comprehensive pipe gallery penetrating through the wide water channel according to claim 1 is characterized in that: the splicing seam connecting structure is a waterproof strip, a waterproof coating or a multi-point welding structure.