Cold-formed stainless steel double shear bolted connections by transient state test method

Abstract

A total of 37 cold-formed stainless steel double shear bolted connection specimens were tested using transient state test method. The bolts arrangement consisted of two-parallel and four-bolted connections. The specimens of bolted connections were fabricated by three different grades of stainless steel. The three different grades of stainless steel are austenitic stainless steel EN 1.4301 (AISI 304) and EN 1.4571 (AISI 316Ti having small amount of titanium) as well as lean duplex stainless steel EN 1.4162 (AISI S32101). The connection tests were conducted at three different load levels of 0.25, 0.50 and 0.75 of the failure load at ambient temperature. The tendency of the test strength reduction of the stainless steel double shear bolted connections conducted using the transient state test method is similar to those results obtained by the steady state test method. However, the critical temperatures obtained from the transient state test results are generally slightly higher compared with those deduced from the steady state test results at the three different load levels. The austenitic stainless steel grade EN 1.4571 (AISI 316Ti) generally performed better than the other two stainless steel grades in transient state tests as higher values of critical temperatures were obtained. Two failure modes, namely the bearing and net section tension failures, were observed in the transient state tests.