Model studies of the vibrations of structures during earthquakes, based on ground accelerations instead of on ground displacements*

One of the most important problems in the field of earthquake engineering with the dynamics of structures. Any building is an elastic system. As , its deflections (stresses) during an earthquake may depend on its own characteristics as well as on the nature of the ground motion. An building is a relatively complicated dynamic system, usually of many of freedom and with considerable internal friction. The treatment of problem may be simplified by the assumption that this internal friction is to viscous damping. A further simplification results from first systems of one degree of freedom, combining these results if the behavior a more complicated system is desired.