DAMAGE DISTRIBUTION LAW OF WEAK-BEAM TYPE FISHBONE-SHAPED MULTI-STORY STEEL FRAMES

The total energy input into a structure exerted by an earthquake is a very stable amount. Then, it becomes very important to predict the distribution of damage for the seismic design purpose. The damage distribution is influenced by the distribution of the strength and the stiffness ratios of beam to column. In this paper, a basic rule which governs the distribution of damage in weak-beam type multi-story steel structures is derived through elasto-plastic response analysis, and is expressed in a simple formula. Applied analytical model is fishbone-shaped frames. The results of analysis are summarized in a form of the damage concentration index n.