Numerical Analysis And Safety Assessment Of Mechanical Behavior Of Pile Group Foundation In Soft Subgrade Of Large Coal Yard

With the rapid progress of China's economic,the situation which load and even overload in industrial plants,road embankments,bridge,port and wharf often happen.In the soft foundation,the pile foundation not only will produce the lateral displacement under the pile load,but also will produce the bigger additional moment.There is a security risk for the self-bearing condition of the pile foundation and the safe use of the upper structure.Therefore,it is necessary to study the mechanical behavior of pile foundation in soft soil area and to evaluate it whether meets the requirements of stability and bearing capacity and put forward rationalization proposals.This paper takes the soft foundation reinforcement of BALINGIAN(2x300MW)coal-fired power station in Malaysia as engineering background,based on the large-scale general finite element software ABAQUS,taking the influence of pile-soil interaction into account.Through the establishment of 2D and 3D finite element analysis model,this paper studies the force characteristics of pile group foundation in coal storage yard,and completes parametric analysis,the main contents of the paper include:(1)The simplified two-dimensional finite element analysis model of pile group foundation in soft foundation is established.The displacement of soil,and displacement and internal force of the pile are analyzed systematically.The influence of load on pile foundation deformation and stress was studied,and the rationality of modeling was confirmed by comparison with actual situation.(2)Combined with the construction survey report,we can select the three typical sections,and establish 2D and 3D finite element modeling.And compared with elastoplastic constitutive foundation-linear elasticity and elastoplastic group pile foundation,analysis its force characteristics and make a rational evaluation on the stability of group pile foundation.(3)Based on the above analysis,we can select the most unfavorable section.Comprehensively considering the actual situation,the elastic modulus of silty soil is taken as the parameter.The influence of the pile foundation on the force and deformation is studied.On this basis,the bearing capacity of the pile in the foundation after vacuum preloading is checked,which can provide reference for the further design and construction of the related project.