抄録
This paper deals with damages of structures subjected to severe earthquakes. Energy concept introduced by Housner has great advantages in simplicity and applicability to estimation of structural damages under earthquakes. Housner assumed that energy input contributable to structural damages can be expressed as [numerical formula] where E_D : energy input causing damages M : total mass of a structure y^._<e, max> : velocity response spectrum. However, the verification of the assumption has not been established yet. A general law on vibrational systems can be written as W_p+W_e+W_n=W_E, where W_E : total energy input exerted by an earthquake W_p : energy absorption due to plastic deformation of a structure W_n : energy absorption due to damping W_e : elastic vibrational energy. Structural damages correspond to W_p, and E_D may correspond to W_p+W_e. Through vast amount of numerical analyses on inelastic vibrational systems, each component of energy in the above equation was evaluated and it was found that Housner's assumption is basically accepted.
