Experimental and numerical investigation of novel triangular headed one-sided bolted T-stub connections

The reliable one-sided bolts constitute a vital component of fully bolted joints in demountable steel structures. In this study, an innovative triangular headed one-sided bolt (THOB) based on the traditional hexagon headed bolt (HHB) was proposed, and the tensile performance of T-stubs using the THOBs has been investigated through experimental and numerical approaches. Monotonic tensile tests were performed on 25 THOB bolted T-stubs to analyze the failure modes and load-carrying performance of the specimens. The test results disclosed that, beyond the three typical failure modes stipulated in the Eurocode 3, the specimens exhibited a characteristic failure mode, namely, limit groove pull-off failure. Finite element models, validated by the test results, were employed for the parametric analysis to compare the load-carrying performance of THOB bolted T-stubs with that of HHB bolted T-stubs. The finite element analysis results indicated that the average ratio of the plastic loadcarrying capacity of THOB bolted T-stubs to HHB bolted T-stubs was close to 0.88. Furthermore, the loadcarrying capacity of THOB bolted T-stubs was evaluated using existing specifications for comparison with the experimental and numerical results, and Eurocode 3 calculations for the plastic load-carrying capacities of THOB bolted T-stubs demonstrated a commendable level of precision. Finally design recommendations were put forward based on the test and finite element analysis results.