Improvement Of One-dimensional Time Domain Nonlinear Seismic Response Analysis Program CHARSOIL

The program CHARSOIL is one of the typical representative programs for timedomain nonlinear site seismic response analysis program,and it has been included in the international influential textbook Geotechnical Earthquake Engineering(Kramer,2007).The study found that the calculation results of the program often do not match the observed facts.Therefor based on the summarization of related research,this paper improves the boundary conditions and constitutive model of one-dimensional time domain nonlinear seismic response analysis program CHARSOIL,and validates the improved program M-CHARSOIL by using observation data from KiK-net station in Japan.Then the reliability of program M-CHARSOIL has been compared with the widely used programs in the world.The main research achievements in this paper are described as follows:1.The basic principles and methods used by CHARSOIL were introduced.And the program CHARSOIL's shortcomings of its rigid boundary conditions and constitutive models were analyzed.Then based on viscous boundary conditions and dynamic skeleton constitutive model,an improved program M-CHARSOIL were developed.2.Two typical stations of KiK-net in Japan were selected,and the improved program M-CHARSOIL was used to simulate the observation data of the station.Then the peak ground acceleration,response spectrum and other parameters were given.In order to verify the reliability of M-CHARSOIL,the actual ground motion records and the calculation results were compared.The results show that when the input ground motion peak is less than 100 gal,the error is small;when it exceeds 100 gal,the calculation result is obviously too large,so the reliability of the calculation program needs further verification;3.Using the station data of KiK-net in Japan,compared and analyzed the similarities and differences between M-CHARSOIL and the domestic and foreign popular use programs DEEPSOIL,LSSRLI-1 and SOILQUAKE,then reviewed their application scope,provided a basis for selecting reasonable programs for engineering applications.