Construction method of recoverable deep foundation pit outer wall integrated structure

Abstract

The invention discloses a construction method of a recoverable deep foundation pit outer wall integrated structure. The construction method comprises the steps that retaining wall constructional columns are replaced by socket type steel columns, a retaining wall is built on the outer side of a basement outer wall by using two layers of prefabricated brick tire membranes, a waterproof coiled material is laid between the two layers of prefabricated brick tire membrane retaining walls, opposite-pulling connecting pieces can be pre-embedded in the inner-layer prefabricated brick blank film retaining wall to fix the formwork, an enclosing wall for pouring the outer wall is formed, and therefore the space for pouring the outer wall is formed. According to the construction method, firstly, the situation that the construction amount is increased due to the fact that inclined struts are arranged before outer wall pouring can be avoided, the stability, pressure resistance and perpendicularity of the prefabricated brick forming die wall are enhanced through the steel columns, meanwhile, the number of the socket type steel columns is small, the distance between the supporting structure and the socket type steel columns is not limited by the small construction space any more when the distance is adjusted, and the distance between the supporting structure and the socket type steel columns can be adjusted to be less than 0.8 m; secondly, constructional columns such as the steel columns are flexible to assemble and disassemble, and the construction amount is greatly reduced; and thirdly, the construction method greatly reduces the dependence on the outer side space of the outer wall, so that the construction amount is greatly reduced. According to the construction method, the construction period can be greatly shortened, and the foundation pit design can be more flexible and more economical.

Description

technical field [0001] The invention relates to the field of construction of external walls of deep foundation pits, in particular to a recyclable construction method for the integrated structure of external walls of deep foundation pits. Background technique [0002] In order to meet the basic requirements of workers’ working space in the construction of traditional deep foundation pit basement exterior walls, the space reserved between the side walls of the supporting piles and the exterior walls of the basement needs to be at least 1.2 meters away from the working surface according to the actual depth of the foundation pit, so as to barely meet the requirements of the exterior walls. The basic requirements for the working space of formwork installation and removal, exterior wall waterproofing and protective layer construction, scaffolding erection, etc. The erection of formwork brackets in the traditional construction process is as follows: figure 2 As shown, the outer wa...

AI Technical Summary

Problems solved by technology

If it is limited by the site or there is a deviation during the construction of the side wall support pile, the working space will be reduced, and in the actual construction process, the actual reserved working surface is often much smaller than the design reserved working surface, so at this time The construction conditions are extremely unfavorable to the construction of the above-mentioned existing exterior wall construction methods, and ultimately have a great negative impact on project quality and construction safety.

[0004]On the other hand, during the construction of the existing exterior walls, first, the space reserved between the support piles and the exterior walls of the basement is too large, which will directly result in the amount of earth excavation 1. The amount of backfill increases, thereby increasing the construction cost; second, there are many processes, and the overlapping of the front and rear processes is affected by the narrow space, resulting in low work efficiency, which has an adverse impact on basement construction

[0005] To solve the above problems, such as image 3 , CN109736353B has announced the construction method of compound type unilateral formwork deep foundation pit basement exterior wall, but there are following problems in this method: 1. prefabricated protective wall section, prefabricated protective wall lower section need to use adjustable pull-joint and enclosure structure Make connections to maintain the verticality of the prefabricated protective wall. Since the side of the prefabricated protective wall facing away from the enclosure structure needs to be equipped with a waterproof structure, in order to avoid local leaks in the waterproof structure, the adjustment structure of the adjustable pull-joint can only be set On the side of the prefabricated protective wall facing the enclosure structure, the distance between the prefabricated protective wall and the enclosure structure must be controlled within 1.2 meters, so that workers can enter the gap for construction, and there are a large number of adjustable tension members to be installed , in order to maintain the verticality of the entire prefabricated protective wall, so the project volume is huge and the operating space is small. In reality, the plan has a risk of collapse due to the prefabricated protective wall, and the workers lack a spacious escape channel when working in this area, so they are resisted by the workers. Not as the first choice; 2. The side of the waterproof structure facing away from the enclosure structure needs to build a sandwich wall for protection. Due to the weak strength of the waterproof structure, it is difficult to prevent the formwork from collapsing by pulling the formwork of the pouring sandwich wall with the connecting piece. Therefore, In this scheme, diagonal braces are supported on the side of the formwork facing away from the waterproof structure. However, considering the large area of ​​the clamping wall, the construction volume of the diagonal braces that need to be set is astonishing, and the tension connectors are pre-embedded in the prefabricated protective wall It will destroy the waterproof effect of the waterproof structure

Based on the above reasons, CN109736353B is only used as a technology on paper, but in reality, the construction is too difficult and often not adopted, but a more traditional construction method is adopted

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