点载荷作用下岩石塑性特征及分类

为了研究不同种类岩石在点载荷作用下塑性特征,通过室内实验测定了花岗岩、细砂岩、黄砂岩、玄武岩、粉砂岩、红砖在点载荷作用下位移-载荷曲线,得到了6种类岩石力学特性和塑性特征。粉砂岩、红砖和玄武岩的强度接近;黄砂岩、花岗岩和细砂岩强度呈现线性增大,且与刚度变化趋势相一致。随着强度的增加,变形呈现先急剧增长后缓慢下落的特点。根据曲线规律对岩石进行分类和分级,黄砂岩、粉砂岩、玄武岩和红砖均属于脆塑性岩石;玄武岩为塑性岩石,细砂岩为脆性岩石。通过塑性系数对岩石进行分类,细砂岩为脆性岩石,级别为1级,塑性系数为1;玄武岩为塑性岩石,级别为6级,塑性系数为6~∞;花岗岩塑性黄砂岩塑性粉砂岩塑性红砖塑性。岩石越致密越均质,弹脆性越好;孔隙越多越离散,塑性变形越明显。

Plastic Characteristics of Rock under Point Load

In order to study the different kinds of rock plastic characteristics in point load, the determination of granite, sandstone, siltstone, Huang Shayan, Xuan Wuyan, red brick in point loading load-displacement curves were obtained through laboratory experiment, mechanical properties of 6 kinds of rock and plastic characteristics. The strength of siltstone, red brick and basalt is close, and the strength of Huang Shayan, granite and fine sandstone increases linearly, and coincides with the trend of stiffness. With the increase of strength, the deformation presents the characteristics of rapid growth and slow drop. According to the law of curve classification and classification of rock, Huang Shayan, siltstone, Xuan Wuyan and red brick belong to brittle plastic rock, Xuan Wuyan is plastic rock, fine sandstone is brittle rock. Through the plastic coefficient classification of rocks, sandstone for brittle rock, grade 1, plastic coefficient is 1, basalt plastic rock, grade 6, plastic coefficient for 6~ 8, granite plastic