Abstract: Based on the effect of rock specimen on Young＇s modulus, the influence mechanism of confining pressure on Young＇s modulus is discussed. The increase of confining pressure, resulting in the decrease of the micro-crack density and the closure of the crack, and the fictional sliding effect between crack and slip surface are main causes of the increase of Young＇s modulus. Through the analysis of test data, it is concluded that the Young＇s modulus increases with the increase of confining pressure. While the confining pressure becomes bigger than the compacting strength, the increasing of Young＇s modulus becomes diminished and tends to be a definite value gradually. The formula of the relation between the rock Young＇s modulus and the confining pressure is determined, which reflects the characteristic that the micro-crack density decreases in an exponential relationship with the increase of confining pressure.

Key words: confining pressure , Young＇s modulus , micro-crack density , compacting strength ;

摘要： 从岩样对杨氏模量的影响出发,分析了围压对杨氏模量的影响机理,围压的增大引起裂纹密度的减小及裂纹 的闭合与裂纹面的摩擦滑移作用是造成杨氏模量提高的主要原因。通过试验分析,认为岩石的杨氏模量随围压的 增大而提高,当围压大于岩石的压密点强度后,杨氏模量的增大呈减小趋势而趋于定值;提出了岩石杨氏模量与围 压关系的表达式,反映了裂隙密度随围压的增加呈指数关系减小的特征。

关键词: 围压, 杨氏模量, 裂纹密度, 压密强度