The literature on the design, construction, testing and performance of resin bonded rock bolts has been surveyed, and particularly focused on vibration prediction and the behaviour of rock bolts when subjected to dynamic loading. The dynamic load transfer mechanism, the dynamic and static service behaviour of two-speed resin bonded rock bolts in microdiorite, and the dynamic behaviour of rock anchorages in mudstone when subjected to tunnel blasting have been investigated through two extensive full-scale field and laboratory tests. The investigation on two-speed resin bonded rock bolts has been performed with twenty four rock bolts installed within 1.1 to 5.7 m from the blasting face. All rock bolts were instrumented using load cells and accelerometers fixed on the anchor heads to monitor the instantaneous dynamic load and residual static load, and axial dynamic vibration of the bolts. Eight of the bolts were also instrumented with five inserted load cells along their length to monitor the dynamic load transfer mechanism and static load distribution. The dynamic load transfer mechanism, the dynamic response of rock bolts with scaled distance, and safe distance for the installation of permanent resin bonded rock bolts have been established. The effects of prestress load (from 0 to 100 kN) and distance to blast source have been assessed. For the investigation on mudstone anchorages, nine anchorages were instrumented with accelerometers at the anchor heads and in the vicinity of the fixed anchor zone to monitor vibration levels when subjected to nearby tunnel blasting. Residual loads were checked by lift-off test A relationship of vibration between the anchor head and fixed anchor has been established, and a safe peak particle velocity of 48 mm / s has been established. A physical model, which simulates the dynamic and static behaviour of resin bonded bolts subjected to blast loading, has been developed. Three instrumented bolts were tested, and different prestress and confining pressure levels were applied to the instrumented bolts.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:601346 |
| Date | January 1993 |
| Creators | Xu, Haixue |
| Publisher | University of Bradford |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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