|
|
|
| An analytical model of jointed rock bolts under the combination of tensile and shear loads |
| LI Yuzong1，2，LIU Caihua1 |
| (1. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. University of Chinese Academy of Sciences，Beijing 100049，China) |
|
|
|
|
Abstract Current bolting theories without considering the dowel effect fail to reveal the mechanism of jointed rock bolts. In this paper，the mechanical characteristics of jointed rock bolts were discussed，and the transverse section of shear deformation of a jointed rock bolt was considered as a beam to establish the structural mechanical model. The load and deformation compatibility relationships of the transverse shear length were deduced. Based on the structural mechanics and the principle of minimum potential energy，an analytical model of jointed rock bolts was developed and an algorithm for calculating the transverse shear length on one side of the joint plane was proposed. It is revealed that the resistance of a jointed rock bolt is provided by the combination of the axial and shear forces，which act at the intersection of the bolt and joint. The resistance obeys a parabolic relationship. The larger the bolting angle，the greater the dowel effect. With increasing the bolting angle，the transverse shear length increases，but the resistance of the bolt decreases. Comparisons between the developed model and the experimental data were performed. It is shown that the proposed method agrees well with the experimental data and is thus proved to be reasonable and reliable.
|
|
|
|
|
|
| | |
2016, Vol. 35 
