Supporting Schemes For Deep Foundation Pit And Influence To Surrounding Buildings

With the rapid development of social economy in China,the process of urbanization is becoming more and more intense.The appearance of the major first-tier cities and super first-tier cities shows that the urban population in China is increasing constantly.In urban life,people's demands for the use of transportation and building facilities are constantly increasing,and new changes have taken place in the scale and use function of services,this requires that the speed of construction and construction in our country match the speed of social development with the speed of technical needs.It is also necessary to ensure the stability of building foundation construction when building construction is carried out.There are great differences between the site geological conditions during construction and exploration,and hidden dangers and accidents are easy to occur when foundation construction is carried out,at this point,it is necessary to put forward the support optimization scheme matching with the construction of various building foundations.In this paper,a practical case will be presented to show how to use reasonable analysis and empirical conclusions to select a suitable foundation pit support scheme.The actual case selected in this paper is the supporting facilities installation project of the underground foundation pit construction of Jiangxi Industrial Design Center.The construction site is located in the Jiangxi Arts and Crafts Museum,Donghu District,Nanchang City,Jiangxi Province.There are only a lot of old buildings around the north side of East Beijing Road and the west side of Jiangnan road,it belongs to the construction site with complex surrounding environment.According to the drawings,the total floor area of the building to be built is 41,786 square metres.According to the calculation,the excavation depth is about20.10 meters underground,the relative elevation of basement slab is-1.8 meters and-6.4 meters,the thickness of cushion is 0.5 meters,the leveling elevation is 20.10 meters,and the depth of foundation pit to be excavated is 6.9 meters.Because the construction area is small and the construction period is one year,the impact on the surrounding environment should be minimized when the deep foundation pit isconstructed.According to the comparison,the comprehensive analysis is carried out from the aspects of technology and economy.After fully considering the actual site conditions and the construction environment,the computer modeling and calculation shows that the corner brace has little influence on the basement construction,this deep foundation pit construction needs to adopt "the construction method pile + the angle brace" the union support system plan.In this paper,the matters needing attention in the construction and the influence of the ground water on the construction are studied,and the matters needing attention in the construction are also studied after it is determined that the combined support method is used for the pile and the angle brace,especially in the construction of supporting pile and embedded parts,it is necessary to pay special attention to the range of deviation and the requirement of technical index for stability.It is realized by monitoring in time during the construction of every step supporting project to find out the time point of the problem and solve it in time.From the determination of the supporting scheme to the completion of the deep foundation pit construction of the support system,and finally to complete the removal of the support system,to complete the replacement of the technical standards and construction points have done a detailed study and investigation.