Bidirectional Behavior of Structural Clay Tile Infilled Frames

Abstract

Several bidirectional tests were performed on structural clay tile infilled steel frames to assess the interaction of in-plane and out-of-plane forces and to understand the behavior of damaged infills. Tests consisted of in-plane and out-of-plane uniform lateral load tests, out-of-plane drift tests, sequential tests (in-plane damage followed by out-of-plane loading, and out-of-plane damage followed by in-plane loading), one combined in-plane and out-of-plane test, and a seismic shake table test. Infill panels had sufficient out-of-plane stability under both inertial (uniform) loads and imposed drift loads. This stability was due to arching, or the development of in-plane membrane forces. The interaction of in-plane and out-of-plane forces was not significant, particularly at moderate levels of loading. The primary effect of sequential loading was loss of in-plane stiffness due to elimination of the diagonal cracking limit state. Under combined in-plane and out-of-plane loading, the infill remained remarkably stable, even after much damage to the masonry panel.