Experimental Study on the Self-Protection Performance of Anchor Bolts with Energy-Absorbing Tails

Abstract

In this study, the typical modes, hazards, and causes of rebar failure were analyzed under the condition of large deformation around deep roadways induced by dynamic disasters such as rock burst. We found that the fundamental causes of the tail failure of rebars are their low elongation and poor energy-dissipation performance. To solve this problem, we designed axial splitting components as energy absorbers, and developed anti-impact and energy-absorbing tail bolts, and in this paper, we elaborate on their working principles. The behavior of energy absorbers of a specific size (wall thickness of 4 mm and inner diameter of 26 mm) was experimentally investigated under both static and dynamic loading conditions. The self-protection performance of these novel bolts was studied using quasi-static tensile tests. The results show that they deformed stably with a constant resistance under both static and dynamic loading. The constant resistance value of the splitting energy absorbers was as high as 125–150 kN, while the energy-absorption efficiency was 0.111–0.127 kJ/mm. The energy absorbers effectively increased elongation, delayed yielding, and enhanced the energy-dissipation capacity of rebars, which resulted in the self-protection of bolts subject to large deformation loading.