Title: Effect of profile bolt in bond strength fully grouted rock bolts using analytical and experimental methods
Authors: Mostafa Ghadimi
Addresses: Department of Mine, Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran
Abstract: Steel rock bolts are widely used in mining and tunnelling engineering to support underground excavation or to stabilise a rock mass. The anchorage capacity of fully grouted bolts has been studied for many years; however, the fully grouted rock bolts and its effect is poorly understood. A new analytical approach able to predict the bond strength of fully grouted rock bolts is proposed in this paper. Input parameters are: rib profile shape, height, width, angle of wrap and spacing, axial bolt pull-out force, material properties. As for the analytical part, the basis of the new analytical solution for the prediction of the load-displacement curve was developed. Derived mathematical equations enable calculations of grout displacement in elastic and elasto-plastic behaviour. In the experimental part, six bolts in situ pull-out tested were compared with the predictions of the new analytical approach and this comparison led to the validation of this approach.
Keywords: bond strength; fully grouted rock bolts; profile bolt; pull-out test.
International Journal of Mining and Mineral Engineering, 2017 Vol.8 No.2, pp.156 - 168
Received: 30 Apr 2016
Accepted: 15 Jan 2017
Published online: 20 May 2017 *