Parameter Identification of Elastic Modulus at Futatsuishi Site

Abstract

This paper presents a parameter identification of the elastic modulus of the ground using the finite element method. In this research, the elastic modulus is identified to minimize the performance function with consists of the square residual between observed and computed result. Using the adjoint method, which is one of the techniques of inverse analysis. The actual site is assumed as an elastic body. To calculate the velocity of wave transmitted through the stratum, the equilibrium of stress equation, the strain-displacement equation, and the stress - strain equation are employed. To identify the elastic modulus, the gradient of the performance function is calculated using the adjoint equation. The Sakawa- Shindo method is employed for the minimization algorithm. The Galerkin method and the Newmark ß method are employed to the space and temporal discretizations, respectively. The elastic modulus at the Futatsuishi site can be solved by this analysis.