Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6783288 | Tunnelling and Underground Space Technology | 2016 | 8 Pages |
Abstract
A series of rock bolt pull tests were carried out in the laboratory to determine the critical embedment length of a specific type of fully cement-grouted rebar bolt. The rebar bolt is 20Â mm in diameter, and it is widely used in underground excavations in Norway. Three water-cement (w/c) ratios were used in the tests. It was discovered that the critical embedment length of the rock bolts was approximately 25Â cm for the water-cement ratio 0.40 (the corresponding uniaxial compressive strength (UCS) of the grout is 37Â MPa), 32Â cm for the ratio 0.46 (UCS 32Â MPa), and 36Â cm for the ratio 0.50 (UCS 28Â MPa), for the specific type of cement, Rescon zinc rock bolt cement. It was found that the bond strength of the rock bolt is not a constant but is related to the embedment length. The bond strength was linearly proportional to the UCS of the grout.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geotechnical Engineering and Engineering Geology
Authors
Charlie C. Li, Gunnar Kristjansson, Are Håvard Høien,