High-strength bolts are widely used in structural connections, and the preload affects failure behavior of bolts. In this paper, a variable cross-section bolt (VCSB) with weakened strength to induce fracture is designed. Quasi-static tensile experiments different torque values were performed on VCSB. The torques 0, 430, 610, 820 N·m applied VCSB connection structures before test. load–displacem...