Model Test Study on the Optimization of Anchorage Parameters of Bolts in Tunnel with Fault Fracture Zone

Abstract

To study the influence of different borehole diameter, bolt diameter and grouting ratio on the anchorage quality, pull-out model tests were carried out by using the orthogonal test method which can greatly reduce the number of tests and not decrease the test feasibility. The experiments were carried out by using the combination of different test parameters, and the data obtained from the experiment were analyzed. The results show that the drilling diameter has significant influence on the pulling force. Reasonable selection of grouting ratio can improve the durability. The anchorage parameters are not simply superimposed. To get the best anchorage effect, it is necessary to determine the optimal combination of anchoring parameters under specific geological conditions.