CN111305231A

CN111305231A - Composite steel plate wall semi-rigid cantilever foundation pit supporting system

Info

Publication number: CN111305231A
Application number: CN202010248296.4A
Authority: CN
Inventors: 冉隆林; 宋凯; 戴罡; 房凯; 王露; 朱立峰; 谢哲峰; 白志鹏; 刘泽; 马文辉
Original assignee: Tianjin No2 Construction Engineering Co ltd
Current assignee: Tianjin No2 Construction Engineering Co ltd
Priority date: 2020-04-01
Filing date: 2020-04-01
Publication date: 2020-06-19

Abstract

The invention relates to the technical field of building construction, in particular to a composite steel plate wall semi-rigid cantilever foundation pit supporting system which comprises a plurality of front row U-shaped steel plates, a plurality of rear row U-shaped steel plates and a water-stop curtain, wherein the front row U-shaped steel plates and the rear row U-shaped steel plates have the same structure, the front row U-shaped steel plates are buckled with each other, the rear row U-shaped steel plates are buckled with each other, the water-stop curtain is positioned between the front row U-shaped steel plates and the rear row U-shaped steel plates, the maximum bending moment parts of the front row U-shaped steel plates and the rear row U-shaped steel plates are provided with a rotary spraying cement reinforcing section, and a shearing force transmission reinforcing steel bar is inserted in the rotary spraying cement reinforcing section. According to the invention, the two soil retaining structures and the inter-pile dowel cement soil act together, so that the horizontal displacement of the cantilever supporting structure is greatly reduced, and a horizontal supporting structure in a pit can be completely cancelled.

Description

Composite steel plate wall semi-rigid cantilever foundation pit supporting system

Technical Field

The invention relates to the technical field of building construction, in particular to a composite steel plate wall semi-rigid cantilever foundation pit supporting system.

Background

At present, a deep foundation pit project in a soft soil area generally adopts a row pile and horizontal inner support structure, the pile forming construction period is long, and the inner support is not beneficial to earth excavation and basement structure construction. And the side wall leakage caused by soil loss among piles and failure of the waterproof curtain not only hinders construction, but also has great harm and is a main cause of foundation pit collapse accidents.

Disclosure of Invention

The invention aims to overcome the defects of the technology and provides a composite steel plate wall semi-rigid cantilever foundation pit supporting system.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a compound steel sheet wall semi-rigid cantilever excavation supporting system which characterized in that: including a plurality of front-seat U-shaped steel sheets, a plurality of back row U-shaped steel sheets and stagnant water curtain, the structure of front-seat U-shaped steel sheet and back row U-shaped steel sheet is the same, and a plurality of front-seat U-shaped steel sheets are in the same place in the lock joint each other, and a plurality of back row U-shaped steel sheets are in the lock joint each other, stagnant water curtain is located between front-seat U-shaped steel sheet and the back row U-shaped steel sheet, is equipped with the cement of spouting soon at the maximum position of moment of front-seat U-shaped steel sheet and back row U-shaped steel sheet and consolidates the section, and the interpolation has the shear force to.

Preferably, two sides of the front row of U-shaped steel plates and two sides of the rear row of U-shaped steel plates are respectively provided with a U-shaped groove, and the U-shaped grooves on the two adjacent steel plates are buckled with each other to form a whole.

Preferably, a reinforced concrete slab is arranged on the tops of the front row of U-shaped steel plates, the rear row of U-shaped steel plates and the waterproof curtain.

The cantilever foundation pit supporting system has the beneficial effects that the composite steel plate wall cantilever foundation pit supporting system adopts two rows of inner and outer U-shaped steel plates, the cement water-stop curtain is arranged in the middle, the rotary spraying cement reinforcing section is designed at the position with the largest bending moment, and the shear force transmission reinforcing steel bars are inserted in the U-shaped steel plates, so that the problems that the front row of supporting and the rear row of supporting are independent from each other and the bearing force cannot be effectively superposed are solved, the original flexible steel plate piles form a rigid whole, the two soil retaining structures and the reinforced cement soil between the piles act together, the horizontal displacement of the cantilever supporting structure is greatly reduced, and the horizontal supporting structure in the pit can be completely cancelled. Underground structure completion retaining pile can all be retrieved, material-saving green.

Drawings

FIG. 1 is a side view of the present invention;

FIG. 2 is a top view of the present invention;

FIG. 3 is a diagram of the form of the structure in FIG. 18;

fig. 4 is a graph of the structure simulation comparative calculation in fig. 18.

Detailed Description

Spatially relative terms such as "above … …", "above … …", "above … …", "above", and the like, may be used herein for ease of description to describe the spatial relationship of one feature or characteristic to another feature or characteristic as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

As shown in fig. 1 and 2, a composite steel plate wall semi-rigid cantilever foundation pit supporting system comprises a plurality of front row U-shaped steel plates 1, a plurality of rear row U-shaped steel plates 2 and a waterproof curtain 3, wherein the front row U-shaped steel plates and the rear row U-shaped steel plates are identical in structure, the front row U-shaped steel plates are buckled with each other, the rear row U-shaped steel plates are buckled with each other, the waterproof curtain is positioned between the front row U-shaped steel plates and the rear row U-shaped steel plates, a rotary spraying cement reinforcing section 4 is arranged at the maximum bending moment position of the front row U-shaped steel plates and the rear row U-shaped steel plates, and a shear force transmission reinforcing steel bar 5 is inserted in the rotary spraying cement reinforcing section. The U-shaped grooves 6 are respectively arranged on two sides of the front row of U-shaped steel plates and the rear row of U-shaped steel plates, and the U-shaped grooves on the two adjacent steel plates are buckled with each other to form a whole. And reinforced concrete slabs 7 are arranged at the tops of the front row of U-shaped steel plates, the rear row of U-shaped steel plates and the waterproof curtain.

The cantilever foundation pit supporting system of the composite steel plate wall adopts two rows of U-shaped steel plates inside and outside, a cement soil waterproof curtain is arranged in the middle, a rotary spraying cement reinforcing section is designed at the position with the maximum bending moment, and a shear force transmission reinforcing steel bar is inserted in the rotary spraying cement waterproof curtain, so that the problems that the front row of supports and the rear row of supports are independent from each other and the bearing capacity cannot be effectively superposed are solved, an original flexible steel plate pile forms a rigid whole, the two soil retaining structures and the inter-pile reinforcement cement soil are jointly acted, the horizontal displacement of the cantilever supporting structure is greatly reduced, and the horizontal supporting structure in a pit can be completely cancelled. Underground structure completion retaining pile can all be retrieved, material-saving green.

Through calculation in various forms, the total bending moment of the supporting structure is the minimum, the stress of the piles in the front row and the rear row is the most uniform, the simulation comparison calculation of the structural form in 18 is shown in fig. 3 and fig. 3, through comparison analysis calculation, the total bending moment of the supporting structure is reduced by 55%, the stress difference of the piles in the two rows is only 24% at the maximum, and the horizontal displacement of the top is the minimum.

Compared with the traditional cast-in-place piling system, the U-shaped piles are of continuous structures and have water retaining functions, and the pit wall forms three independent water stop systems by adding one cement soil, so that the possibility of soil loss among piles and foundation pit leakage is almost eliminated. The steel sheet pile construction speed in the soft soil area is extremely high, maintenance is not needed, an inner support is not needed, a foundation pit is completely excavated in an open mode, the construction period can be saved by more than 60%, economic benefits are obvious, and the steel sheet pile construction method is very suitable for earth excavation operation in the soft soil area with the depth range of 6-10 m.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a compound steel sheet wall semi-rigid cantilever excavation supporting system which characterized in that: including a plurality of front-seat U-shaped steel sheets, a plurality of back row U-shaped steel sheets and stagnant water curtain, the structure of front-seat U-shaped steel sheet and back row U-shaped steel sheet is the same, and a plurality of front-seat U-shaped steel sheets are in the same place in the lock joint each other, and a plurality of back row U-shaped steel sheets are in the lock joint each other, stagnant water curtain is located between front-seat U-shaped steel sheet and the back row U-shaped steel sheet, is equipped with the cement of spouting soon at the maximum position of moment of front-seat U-shaped steel sheet and back row U-shaped steel sheet and consolidates the section, and the interpolation has the shear force to.

2. The composite steel plate wall semi-rigid cantilever foundation pit supporting system of claim 1, wherein: the U-shaped grooves are formed in the two sides of the front row of U-shaped steel plates and the two sides of the rear row of U-shaped steel plates respectively, and the U-shaped grooves in the two adjacent steel plates are buckled with each other to form a whole.

3. The composite steel plate wall semi-rigid cantilever foundation pit supporting system of claim 1, wherein: and reinforced concrete slabs are arranged at the tops of the front row of U-shaped steel plates, the rear row of U-shaped steel plates and the waterproof curtain.