Studies On Support Structure Of Deep Foundation Pit Under Vehicle Load

In the past, the impact of vehicle load is rarely taken into account in structural design of deep foundation excavation. As China's economic development, more and more vehicles in the city, increase pressure on urban traffic and overloading is quite serious. In the city more and more buildings are often constructed between the buildings or traffic arteries, the influence of vehicle load increases and should be paid more attention. However, the current design code of foundation pit does not specify whether or not to consider vehicle load around the pit, and how to consider such effects.This paper focuses on the calculation method for support structure under the role of vehicle load and some key research.This issue addresses the design of support structure calculation method, calculation of earth pressure, vehicle load conversion and some key issues of these three questions were discussed.On the base on the analysis of the advantages and disadvantages of three support structure design and calculation methods, that the classical method, elastic foundation beam method and the finite element method, the elastic foundation beam method is more practical in engineering calculation, and it can meet the needs of engineering safety. Taking into account the impact of the construction process, the incremental method were proposed in this paper.The rupture angle in the equivalent thickness of soil layer method is the angle with no arrangement for the load. But the rupture angle must change when the vehicle load is arranged. In order to remedy this defect, an improved method was proposed, and specifically the calculative process was presented. Some domestic experiment in the influence depth of the vehicle load showed that the depth of the vehicle load is between 6m to 14m. In addition, large scale research in this area has not started. Some advices of research direction in this issue were put forward.Analyzing a specific case, it shows that vehicle load beside deep excavation really has an effect on support structure, and the vehicle load should be taken into account in the support structure design. The conclusion that the depth of vehicle load is between 6m to 14m is reasonable.