Evaluation of a novel pyramidal design of rock bolt bearing plate using analytical, experimental, and numerical methods

Abstract

Ground failures in underground mines are continuing to occur despite using rock bolt support with higher anchorage. The reason may be attributed to the mismatch between bolt anchorage and bearing plate capacity. Currently, the dome-bearing plates are widely used in the reinforcement of ground which often fails at loads below the bolt anchorage capacity. To address this problem, a novel pyramidal design of a bearing plate is proposed keeping the same size and material properties as the conventional dome plate. To evaluate the performance of pyramidal design, analytical formulations of load resistance, load efficiency, and energy absorption are formulated. In the experimental study, the prototypes of pyramidal design are developed and subjected to compression tests along with the conventional dome plate. The calibrated model of tested bearing plates is simulated using 3-dimensional finite element analysis. The pyramidal plate outperforms the dome plate in performance evaluation in terms of load resistance, load efficiency, and energy absorption. The experimental and numerical results also indicated that the capacity of the pyramidal plate is superior to that of a conventional dome plate. Thus, the proposed pyramidal plate can be used with rock bolt support in underground openings for improved ground control and stability.