Bolted steel connections: Tests on T-stub components

The results of tests on 48 T-stub specimens are presented and discussed. These tests were carried out as part of a SAC Phase If project in order to provide insight into the behavior, failure modes, and ductility of these components. The main variables tested include the size of the T-stub, the gauges of the bolts, and the type and diameter of the bolts. The primary intent was to develop a large database to calibrate simplified models suitable for design. In order to develop these models, a comprehensive instrumentation system that could identify the different components of deformation in the individual T-stubs was utilized. Most of the T-stubs failed by net section fracture through the stem and by tension fracture of the bolts, but generally the failure was after significant plastification had occurred. Other failure modes observed included bolt shear and black shear. The results indicate that current design equations provide conservative estimates of the ultimate strength of the T-stubs but that they are not necessarily good predictors of the governing failure modes.