The Model Experiment And Numerical Simulatio N Of Soil Reinforcement At The Bottom Of Fou Ndationo Pit

With the increasing scale of the foundation pit and surroundings become complicated,although soil reinforcement at the bottom of foundation pit is a common measure for controlling the deformation,it has not been regulated clearly in specification.Scholars often use the numerical simulation to study,the method is single.In this paper,the effect of different reinforcement forms on controlling the deformation of foundation pit is studied by model experiment.The reasonable reinforcement rang under different reinforcement forms is studied by the numerical simulation.This paper includes the following aspects:1、The parameters of rectangular foundation pit are designed and a similar model is made.Baesd on the model experiment,the deformation of foundation pit,earth pressure behind pile and internal force of supporting structure are studied in four cases: full reinforcement、skirt border reinforcement、piers reinforcement and no reinforcement.The effect of three kinds of reinforcement to control the deformation of foundation pit,the change of internal force and the cause of the change of earth pressure are analyzed.2、The same size model was established by ABAQUS,and the rationality of the numerical model is verified by comparing the calculated value with the measured value.3、The reasonable reinforcement rang under different reinforcement forms is studied by the numerical simulation.The reinforcement depth should be 0.3-0.4 times of the excavation depth for full reinforcement.The reinforcement depth should be 0.3-0.4 times of the excavation depth and the width should be 0.35-0.45 times of the excavation depth for skirt border reinforcement.The reinforcement depth should be 0.3-0.4 times of the excavation depth,the width should be 0.35-0.45 times of the excavation depth,the length of the pier should be 0.3~0.35 times of the excavation depth and the distance between the piers should be 0.2~0.3 times of the excavation depth for piers reinforcement.The range analysis method is used to determine the influence of several parameters on the deformation of foundation pit.4、Two practical projects with bottom reinforcement are numerically simulated,and the results are compared with the actual monitoring results.It makes study on the reason for differences in numerical values.The reliability of numerical calculation is further verified.And the reinforcement effect of pit bottom was analyzed.