Underground diaphragm wall construction method utilizing large-diameter reinforced concrete filling pile as connector

Abstract

The invention provides an underground diaphragm wall construction method utilizing a large-diameter reinforced concrete filling pile as a connector. The connector formed by the large-diameter reinforced concrete filling pile is arranged between two cast-in-place underground diaphragm walls, the diameter of the large-diameter reinforced concrete filling pile is not less than 800mm, and reinforcement is carried out to the range of the whole pile. The underground diaphragm wall construction method comprises the following steps: guide wall construction, large-diameter reinforced concrete filling pile construction, heat treatment and still standing, construction of the large-diameter reinforced concrete filling pile and the cast-in-place underground diaphragm walls is carried out in interval sequence, and finally completing a complete underground diaphragm wall structure according to design requirements. The underground diaphragm wall construction method has the advantages that the construction method replaces ground diaphragm wall connector equipment and replaces a part of cast-in-place ground diaphragm wall structure, eliminates the process of being pulled up needed by connector equipment, saves a construction period, and can save concrete cost 85 RMB / m<3> in ground diaphragm wall construction cost. Each ground diaphragm wall is continuous and smooth and does not break, and the leakage problem of the ground diaphragm wall is effectively solved.

Description

technical field [0001] The invention relates to a construction technology of an underground diaphragm wall, in particular to a construction method of an underground diaphragm wall using a large-diameter reinforced concrete pouring pile as a joint width. Background technique [0002] In 1950, Italy began to use underground diaphragm wall technology in reservoir dam engineering, and in 1958, my country introduced this technology. In the mid-1970s, this technology began to be applied to construction, coal mining, municipal and other industries. [0003] As an enclosure structure of underground engineering, ground connection wall is widely used in deep foundation pit engineering. It can be used as a temporary retaining and water-stop structure, or it can replace the basement exterior wall as a permanent underground structure. [0004] The construction process of the ground connection wall is mainly divided into the following parts: guide wall construction, steel cage productio...

AI Technical Summary

Problems solved by technology

[0005] 1. The groove wall is not vertical, causing the position of the locking tube to shift

Due to construction machinery and manual reasons, there is always a problem that the two ends of the finished tank wall are not vertical at the lower part

This results in that when the lock pipe is lowered, the lock pipe cannot be placed in the pre-placed position, which affects the width of the wall and the lowering of the reinforcement cage.

At the same time, the gap behind the lock pipe is too large, which increases the workload of earthwork backfill and is prone to the problem of grout leakage

[0006] 2. The locking tube is not fixed stably, causing the locking tube to tilt

The fixation of the lock pipe includes upper end fixation and lower end fixation: the upper end fixation can be seen and touched, and is easy to control; the lower end fixation is mainly lifted by a crane to a certain height of the lock mouth pipe so that it can freely fall and insert into the soil to fix it. The method is properly controlled, and the lower end of the lock pipe generally does not have a large displacement, but it is difficult to control the quality of underwater operations

It is very easy to cause the locking tube to be unstable and cause the locking tube to tilt

[0007] 3. The problem of backfilling after the lock pipe

After the lock pipe is lowered, it will not be close to the soil, and there will always be a certain gap, and the earthwork must be backfilled, otherwise the concrete will bypass the lock pipe, which will cause great obstacles to the construction of the next continuous wall

However, due to the small gap and full of mud, backfilling is not easy to compact

[0008] 4. The horizontal stiffness of the lock pipe is small, and the lateral pressure is large when the concrete is poured, and its verticality is difficult to control

In actual construction, if there is a horizontal deviation of the locking pipe, it will inevitably cause the width of this wall to exceed the design width, occupying the width of the next wall

The occurrence of this problem and the occurrence of grout leakage jointly caused the problem of narrowing the width of the closed width, causing the vertical joints of each ground connection wall to be not straight and tight, and leakage is very easy to occur

[0009] 5. The problem of pulling out the lock pipe

It is the key to grasp the initial setting time of concrete when pulling out the lock pipe. In actual operation, due to poor grasp of the initial setting time, pulling out early will cause quality accidents. It is difficult to pull out or even break the mouth tube, which is time-consuming and labor-intensive, and may cause quality accidents, which is difficult to handle

Images