Horizontal Connections for Precast Concrete Shear Walls Subjected to Cyclic Deformations Part 1: Mild Steel Connections

This paper represents the second part of a multiphase experimental program undertaken at the University of Manitoba to study the cyclic behavior of prestressed connections for precast concrete shear walls. The first part of the study dealt with the behavior of mild steel connections. In this paper, the results of testing five full-scale prestressed connections subjected to reversed cyclic combined flexure and shear loads are presented. The connections were also subjected to axial stresses normal to the connection to simulate gravity loads. The paper discusses the influence of cyclic vs. monotonic loading, use of prestressed strands vs. prestressed bars and the effect of fully unbonded prestressed bars on the behavior of the connections. Based on the test results, design recommendations for the prestressed connection in seismic zones are presented. A simple analytical procedure is developed to predict the envelope of cyclic response and a numerical design example is included to illustrate the design procedure.