Mechanism study on subcritical crack growth of flabby and intricate ore rock

• Published in: Transactions of Nonferrous Metals Society of China Vol. 16; no. 3; pp. 723 - 727
• Main Author: 袁海平 曹平 许万忠
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2006; School of Resources and Safety Engineering, Central South University, Changsha 410083, China
• Subjects: block caving method; double torsion specimens; fracture toughness; stress corrosion; subcritical crack growth; 亚临界裂纹扩展; 双扭转试样; 岩石试验; 应力腐蚀; 断裂韧度; subcritical crack growth; block caving method; fracture toughness; double torsion specimens; stress corrosion
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(06)60128-3

Double torsion specimens were applied to study the subcritical crack growth of flabby and intricate ore in Jinchuan Ⅲ Mine. The relation between the subcritical crack velocity v and the stress intensity factor K1 is obtained, and the fracture toughness Kic and the lower limit of stress corrosion K0 are determined respectively. The results of test show that the curves of lgK1--lgv and K1--lgv can be well linear, and the high discretion of data are caused by mineral composition, particle size and mechanical property of rock itself. In addition, the subcritical crack growth with stress corrosion of the ore is caused by the united function of two mechanisms, one is the tensile stress and the other is the material at the crack tip. Chemical reaction takes place between the materials and the corrosion medium in the environment and makes the chemical bond break. So, the obtained results provide reliable references for predicting the block caving velocity of the ore in Jinchuan Ⅲ Mine under high horizontal stress condition.