Experimental simulation op progressive collapse of perimeter frames due to out-of-plane behavior

Abstract

The framed-tube structure consists of rigid moment frames in the perimeters and floors which provide lateral-support to prevent perimeter column buckling. When perimeter columns deform toward the outside of the structure, simple connections between floors and perimeter columns may rupture in tension. This behavior is simulated by static tests for laterally-supported columns, where lateral drifts are imposed at each story under the constant axial load. Drift mode shape, axial loading level, and the number of lateral-supports are varied. It is found that: (1) the test results are similar to the predicted response, (2) as the lateral-support strength decreases and as the constant axial load increases, the rupture of lateral-supports occurs at smaller drift demand level, accelerating the progressive collapse, and (3) when higher drift mode shape is imposed on the column with small lateral-support strength, the progressive collapse may occur at very small drift demand level.