Study On The Stability Of Foundation Pit Slope Under Combined Loads

With the development of society and the progrsss of science and technology,city constructions gradually concentrate on the underground.There are more and more underground foundation pits in the city.Some of foundation pits are located in the central area of the city.They will produce big influence on surrounding buildings in the process of excavation.When considering the stability of this kind of foundation pit in the past,we often just consider the influence of external static load around,but the vehicle dynamic load is also an important factor that cannot be ignored.This thesis is based on the stability of foundation pit slope under combined loads and the enclosing mearsures.I complete the following works:Firstly,according to the survey of traffic information near the LongXiangJie underground foundation pit,we can raise a method to instead of vehicle dynamic load;Secondly,according to the geological data of LongXiangJie underground foundation pit and the information of vehicle dynamic load,we can choose a appropriate supporting scheme for foundation pit;Thirdly,the excavation process of the model is simulated by using finite difference method.Then calculate the horizontal displacement and vertical displacement of monitoring points;Fourth,analyze the numerical calculation results and actual monitoring value,and to explore the feasibility of around buildings and the foundation pit slope under combined loads;Finally,put forward some corresponding security measures for the foundation pit.The results of research show that the vehicle dynamic load which is simulated by half-wave sinusoidal load is feasible.Under the vehicle dynamic load of a half sine wave action,LongXiangJie underground foundation pit which is set the custodian of the lateral brace of pit can guarantee the stability of foundation pit.The result of numerical calculations is similar to the monitoring data.The important buildings near LongXiangJie underground foundation pit(QingLian restaurant,Oyada building)in the whole excavation process of foundation pit is safe.LongXiangJie foundation pit itself is stable.