Optimum Design And Application Of Deep Foundation Pit Support Method In Seasonal Frozen Area

Deep excavation engineering is a huge systematic project.It is designed both to ensure the safety of retaining structure and to reduce engineering cost.In order to harmonize the relationship between the cost and reliability of engineering project,the optimization design of retaining structure for deep excavation was appeared.Under the safe and dependable premise,it is an important task to select rational supporting structure of foundation excavations,optimize the structure,lower the consumption,realized the best combine of economy and technology.Many problems exist in the optimization design,especially in seasonal frozen soil areas,related optimization design theory is relatively lack of practice,this paper only studies and analyzes the commonly used supporting structure selection and optimization design in seasonal frozen soil area.In this paper,through the study of the method of deep foundation pit support,select the row of anchor bolts,soil nailing wall and frame anchor the three support methods,respectively,the relevant support methods are summarized,calculation of structure load was carried out,and then a dynamic optimization design model was built with engineering cost as the objective function,using a genetic algorithm that mimics the natural evolutionary process and the MATLAB software to compile the corresponding optimization design program.Taking a deep foundation pit project in Harbin as an example,its construction site monitoring and support structure optimization design,especially for the design details of original design of the foundation pit,also took the project cost as the objective function,in the support location,pile diameter,pile spacing and other aspects of specific optimization study on deformation characteristics of foundation pit by using monitoring data,using the actual monitoring data to study the deep horizontal displacement of the foundation pit,the horizontal displacement of the steel sheet pile,the surrounding building settlement and the settlement of the road surface and other aspects of the deformation characteristics.And then use ABAQUS finite element analysis software for numerical simulation analysis,respectively,to establish the original design and optimized of design for the object of the model analysis,the three sets of simulation data after optimization of the actual monitoring data,the optimization of the support structure and the support structure are analyzed synthetically,verify the feasibility of the optimization design model.The rationality of the finite element analysis is analyzed,and the feasibility of the optimization design model is further verified..