Cyclic Testing of Simple Connections Including Effects of Slab

Abstract

The problems with welded moment connections in the Northridge earthquake of 1994 gave researchers incentive to examine the actual contribution of the simple, or shear, connections to the lateral resistance of welded steel moment-frame buildings. With the composite action of the floor slab, these connections may have more lateral resistance than traditionally assumed; thus, they may be used in the repair or retrofit of damaged welded steel moment-frame buildings or used more actively in new construction. To evaluate these possibilities, and to establish the strength, stiffness, and ductility of these connections under cyclic loading, two series of eight full-scale, cyclic tests on shear connections with floor slabs were planned. The first test series has demonstrated the cyclic behavior of the simple connections and has shown that these “pinned” connections have significant moment capacities, both on their own and with the contribution of the floor slab. This paper summarizes the results of the first eight tests.