Statistical assessment of performance of cable bolts under axial loading

D. Li, H. Masoumi, S. Saydam, P. Hagan

Research output: Chapter in Book/Report/Conference proceedingConference PaperOther

Abstract

A wide range of modified cable bolts are currently used for ground support in different conditions in Australian underground coal mining operations. This is mainly based on the belief that the performance of modified cable bolts is better than conventional cable bolts. Despite this positive view, very few studies have characterised the performance of modified cable bolts in service. A new laboratory based pull-out testing facility was employed in this study to investigate the behaviour of two different types of modified cable bolts under axial loading including Garford twin strand bulbed and MW9S (Spiral wire). The impact of different parameters including the compressive strength of the grout and the confining medium as well as borehole diameter on the performance of both cable bolt was investigated. A full factorial experimental program was designed based on Taguchi method to explore the performance of these two cable bolts under different testing conditions. Consequently, an Analysis of Variance (ANOVA) was conducted to assess the weighting contribution of each parameter (e.g. borehole diameter, the compressive strength of grout and confining medium) to the load-displacement performance of Garford twin strand bulbed and MW9S cable bolts. For the Garford twin strand bulbed cable bolt, it was concluded that the compressive strength of the confining medium was the most influential parameter in the determination of the peak and residual loads as well as initial stiffness. It was also observed that an increase in the compressive strength of either the confining medium or the grout led to an increase in peak and residual loads in the Garford twin strand bulbed cable bolt while borehole diameter had no sensible effect on peak and residual loads as well as initial stiffness. In the case of the MW9S cable bolt, the compressive strength of grout had the greatest impact on the peak and residual loads whereby, the peak and residual loads varied directly with grout compressive strength. A 10 mm increase in borehole diameter of MW9P cable bolt had negligible effect on the peak and residual loads as well as initial stiffness.

Original languageEnglish
Title of host publication5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future, YSRM 2019
PublisherInternational Society for Rock Mechanics and Rock Engineering
Pages69-74
Number of pages6
ISBN (Electronic)9784907430047
Publication statusPublished - 2019
EventYoung Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future 2019 - Okinawa, Japan
Duration: 1 Dec 20194 Dec 2019
https://www.ec-pro.co.jp/ysrm2019/index.html

Publication series

Name5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future, YSRM 2019

Conference

ConferenceYoung Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future 2019
Abbreviated titleYSRM 2019 & REIF 2019
CountryJapan
CityOkinawa
Period1/12/194/12/19
Other5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future, YSRM 2019.
Internet address

Keywords

  • Borehole
  • Cable bolt
  • Confining medium
  • Grout
  • Peak load

Cite this

Li, D., Masoumi, H., Saydam, S., & Hagan, P. (2019). Statistical assessment of performance of cable bolts under axial loading. In 5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future, YSRM 2019 (pp. 69-74). (5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future, YSRM 2019). International Society for Rock Mechanics and Rock Engineering.