高围压大理岩卸荷变形破坏与能量特征研究

Study on Unloading Deformation,Fracture and Energy Propertiesof Marble under High Confining Pressure

利用伺服机对大理岩进行了高围压及高围压高水压岩石的卸荷力学试验。基于试验结果,研究了岩样卸围压的变形破坏及其能量特征。结果表明,大理岩峰前卸荷比峰后卸荷表现出更大的脆性;孔隙水压力加速了岩石的脆性破裂,降低了岩石的强度;高围压情况下卸荷比低围压卸荷更容易破坏。

Using the RMT- 150B servo -controlling testing machine, a series of triaxial unloading test under high confining pressure condition was made on marble, at the same time, a series of unloading experiments under high confining pressure and hydraulic pressure condition also was done. Based on the experimental results, the unloading deformation, failure and energy properties of marble specimens were studied. The results are as follows ： when unloaded at pre - peak, the marble is more brittle than unloaded at post - peak ; the high pore water pressure accelerates the brittle fracture of rocks and also reduces their strength;when the marble is unloaded, it is easier to damage under high confining pressure than under low confining pressure.