Design of repairable regular steel buildings with square plan based on seesaw motion of building structure and using DADAS dampers

Abstract

Purpose Almost design code is required for repairability of the buildings after a major earthquake. One such idea is “directed-damage design” (DDD), which means guiding the damage to some pre-decided parts of the structural system. To use the DDD idea for creation of repairable buildings, in this study, a structural system with seesaw motion with respect to a central massive support has been considered for steel buildings with square plan, and the bottom ends of the all circumferential columns at the lowest story have been equipped with double-ADAS (DADAS) dampers, which dissipate a great portion of the seismic input energy. The purpose of this paper is to investigate the hysteretic behavior of DADAS dampers by using finite element analysis. At first, a set of regular steel multistory buildings with five stories have been designed based on the conventional code provisions. Then, the structures of the designed buildings have been changed into the structure with seesaw motion by using, at the base level of the building, a massive central column, eliminating other middle columns, and equipping circumferential columns with DADAS dampers. Design/methodology/approach For repairability buildings in the last three mentioned studies a set of orthogonal strong girders, in the form of grid, has been used. In the present study, the number of bays in the considered building is four in both directions. A major modification has been made in the yielding-plate energy dissipating elements of the circumferential columns, which makes their manufacturing and installation much practical as illustrated in the following sections of the paper. Findings In the proposed rocking structural system for regular multistory steel buildings, creation of the possibility of rocking motion has been done by using a space truss resting on a huge central hinge support at base level with a series of circumferential energy dissipating columns at that level. Originality/value One such idea is DDD idea, which means guiding the damage to some pre-decided parts of the structural system.