The Influence of Resin Thickness on Bolt Bending

Abstract

Load transfer mechanism of bolt has been the subject of increased research for more than three decades, particularly with regard to resin thickness. The influence of increased resin thickness on axially loaded bolts has been widely reported and documented, however there remains a lack of clear understanding of the bolt-resin and rock interaction with different resin thickness particularly when the bolt is sheared. Accordingly, this study is aimed to examine the effect of resin thickness on the bolt-grout- concrete interaction under double shearing conditions. The bending and shearing characteristics of bolts were conducted both in the laboratory and in 3D numerical simulation, and with and without different pretension loads. Both the strength of the concrete and bolt pretension load had been found to have major influence on the shear resistance and shear displacement of the reinforced concrete in all resin thickness. Also, the strength of the surrounding concrete was found to play a greater role than the grout thickness, particularly when the bolt is in pretension.