Influence of distributed inertial mass and stress state on the seismic response

Abstract There are two different ways of taking into account the inertial mass in the seismic response of a structure: the equivalent mass matrix and the lumped inertia mass matrix The former mains a more appropriate situation to the real state of the structure. Inertia mass is often lumped at nodal points. This leads to a diagonal mass matrix and to an excessive elasticity of the structure.