Modeling Approaches in Earthquake Engineering Simulation

Siva Mettupalayam
Dept. of Civil, Environmental and Architectural Engineering
CU Boulder

It is not economical to design engineering structures to withstand severe earthquakes while still remaining in their elastic range. It is necessary to accommodate inelastic deformation. Often, structures are even designed to undergo inelastic deformations at specific locations since the resulting energy dissipation helps protect the other parts of the structure. It therefore becomes necessary to be able to analyze inelastic systems and to obtain their dynamic response to earthquake excitation. Inelasticity of interest is usually plasticity and damage. Dynamic analysis is usually carried out by spatially discretizing the structure, for example using the Finite Element Method, and by numerically integrating the equations of motion. Structural displacements are considered to be the primary unknown functions. In this presentation, an alternate approach based on Lagrangian mechanics to the dynamic analysis of inelastic systems is considered, that seems to offer some benefits.