An Evaluation of the Design and Applications of Yieldable Rock Bolts.

摘要

This report serves as a compilation of developmental,design,and test data for three types of yieldable rock bolts which have been developed and tested. The three types of bolts (termed herein the South African,Bureau of Mines,and Omaha District rock bolts) represent the major thrusts in rock bolt developmental work to date. Much of the information presented was summarized from published reports and personel communications with the designers. The rock bolts evaluated in this study were of two basic types:the 'die-thread'type (the South African and Bureau of MInes bolts) and the 'plug-tubing'type (the Omaha District bolt). With both types of yielding mechanisms the physical shape or configuration of the component parts was shown to be of critical importance. For the two yieldable rock bolts the sensitivity of yield loads to construction methods appears to be comparable.