Study On Optimum Design Of Deep Foundation Pit Support Scheme In Lanzhou

As China's economic development is very rapid,increasing the size of the city makes the urban land there is a relatively tense situation.Therefore,how to make full use of urban space has become very important,especially in the case of increasing urban population,urban land has become very difficult,it is because of this,the city appeared in a large number of underground building space and high-altitude buildings,buildings gradually Reflecting the dense and three-dimensional characteristics.With the development of science and technology,deep foundation pit support form also diversified.However,there are still two problems with the design of deep foundation pit support: the first is that the design of the pit support structure is too conservative,the economic rationality is difficult to meet,leading to the waste of building materials and funds;the second is due to construction causes serious accidents,The root cause is the practice before the theory,theory can not guide the practice.At present,the design of the deep foundation pit support structure is unreasonable,so it is of great significance to optimize the design of the supporting structure.In this paper,a deep foundation pit support project in Lanzhou,through the rational software and ADINA finite element software mainly from the following aspects:(1)By analyzing the function and significance of some parameters of foundation pit support in design,the optimal design of the support structure of deep foundation pit is carried out by using rational software.Finally,the final optimization Structural design.(2)ADINA finite element software was used to establish the three-dimensional finite element model of foundation pit excavation,and the Mohr-Coulomb constitutive model was adopted.In the model,the different boring amount of the pile in the occlusal pile,the different strength of the concrete pile and the influence of the different insertion ratio of the pile on the displacement and bending moment of the pile are analyzed by analyzing the different bite amount in the occlusal pile.The results show that the pile size,the bite amount,the concrete strength used in the concrete pile and the horizontal displacement and bending moment of the pile in the bored pile are obtained.(3)Through the optimization design and analysis of the pile-anchor structure by rational software and finite element software,the pile diameter,pile embedding depth,pile bite amount,concrete strength and pile body Insertion ratio,for other similar projects in Lanzhou provide reference and basis.