BEHAVIOR OF ROCKBOLTS FOUND IN THE EXPERIMENTS OF TWO LOWERING PANELS

Although the rockbolts are used very often as a main member of supports in NATM, the fact is that there are various understanding of the effects of rockbolts and that there has been no specified way of design. It is because the effects of rockbolts have been recognized mainly through experiences and also because there is no good way of investigation of them.This study of rockbolts by two lowering panels is a method of examining more positively the mechanical properties of rockbolts presented by our authors, following the previous study by one lowering panel. This series of the experiments by two lowering panels were made to examine the mechanical properties of a group of rockbolts while the experiments by one lowering panel were made to examine the effects of a rockbolt.This report describes the behavior of rockbolts found through the experiments of two lowering panels including theoretical consideration. And it also describes our view of design of rockbolts.