A STUDY ON TENSION OF ISOLATORS AND DISPLACEMENT RESPONSE OF ISOLATION LAYERS IN MID-STORY AND MULTI-STORY SEISMIC ISOLATED BUILDINGS SUBJECTED TO STRONG GROUND MOTIONS OBSERVED BOTH IN JAPAN AND ABROAD (PART 1) : THE EFFECTS OF STRONG GROUND MOTIONS ON TENSION OF ISOLATORS AND DISPLACEMENT RESPONSE OF THE SEISMIC ISOLATION LAYER IN MID-STORY SEISMIC ISOLATED BUILDINGS

Abstract

Earthquake response analysis of mid-story isolated building was carried out for the strong ground motions observed both in Japan and abroad.

1. As the intermediate isolation layer is installed on higher floors, the displacement response of the isolation layer of mid-story isolated building becomes larger. The strong ground motions cause the displacement response of the isolation layer to exceed the shear strain of the isolator by 400%.

2. Strong ground motions that cause pull-out of the isolators in mid-story isolation building, where mid-story isolation layer is installed on the upper floor, have large pull-out strength in the vertical motion component.