A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Fracture mechanisms of offset rock joints-A laboratory investigation
Abstract To study the failure mechanisms of joints and rock bridges in jointed rock masses a series of uniaxial compression tests were performed on specimens made of rock-like material. Specimens of size 63.5 cm × 27.9 cm × 20.3 cm, made of 72% silica sand, 16% cement (Type I) and 12% water by weight were tested. The joint inclination angle was maintained at 45°, while the offset angle i.e. angle between the plane of the joint and the line that connects the two inner tips of the joints, was changed from 0°–120° with an increment of 15°. The tests were performed using a 2000 kN universal compression machine and a HP data acquisition system. In each sample, five LVDTs were fixed to measure the displacements along and across both the bridge and the joint segment, and the total displacement along the total length of the sample. The failure mechanism was monitored by visual inspection and a magnifier to detect cracks initiation. For each test the failure surfaces were investigated to determine the characteristics of each surface. In all of the tested samples curvilinear cracks called wing cracks initiated at the joints tips due to high tensile stresses concentration. These wing cracks were directed along the direction of the uniaxial load. The coalescence mechanism of two cracks was investigated. Results showed that open cracks could coalesce by shear failure or tensile failure. The coalescence path was found to be mainly dependent on the inclination of the rock bridge between the cracks.
Fracture mechanisms of offset rock joints-A laboratory investigation
Abstract To study the failure mechanisms of joints and rock bridges in jointed rock masses a series of uniaxial compression tests were performed on specimens made of rock-like material. Specimens of size 63.5 cm × 27.9 cm × 20.3 cm, made of 72% silica sand, 16% cement (Type I) and 12% water by weight were tested. The joint inclination angle was maintained at 45°, while the offset angle i.e. angle between the plane of the joint and the line that connects the two inner tips of the joints, was changed from 0°–120° with an increment of 15°. The tests were performed using a 2000 kN universal compression machine and a HP data acquisition system. In each sample, five LVDTs were fixed to measure the displacements along and across both the bridge and the joint segment, and the total displacement along the total length of the sample. The failure mechanism was monitored by visual inspection and a magnifier to detect cracks initiation. For each test the failure surfaces were investigated to determine the characteristics of each surface. In all of the tested samples curvilinear cracks called wing cracks initiated at the joints tips due to high tensile stresses concentration. These wing cracks were directed along the direction of the uniaxial load. The coalescence mechanism of two cracks was investigated. Results showed that open cracks could coalesce by shear failure or tensile failure. The coalescence path was found to be mainly dependent on the inclination of the rock bridge between the cracks.
Fracture mechanisms of offset rock joints-A laboratory investigation
Mughieda, Omer (author) / Alzo'ubi, Abdel Kareem (author)
2004
Article (Journal)
English
Fracture mechanisms of offset rock joints-A laboratory investigation
| British Library Online Contents | 2004
Coalescence of offset rock joints under biaxial loading
| British Library Online Contents | 2006
Stress Analysis for Rock Mass Failure with Offset Joints
| British Library Online Contents | 2008
Stress Analysis for Rock Mass Failure with Offset Joints
| Online Contents | 2008
Stress Analysis for Rock Mass Failure with Offset Joints
| Online Contents | 2008