循环载荷下饱和岩石的应力—应变动态响应  

Dynamic stress-strain response in saturated rocks under cycling load.

作　　者：陈运平[1] 席道瑛[1] 薛彦伟[1] 

机构地区：[1]中国科学技术大学地球和空间科学学院

出　　处：《石油地球物理勘探》2003年第4期409-413,共5页Oil Geophysical Prospecting

基　　金：国家自然科学基金(4017050)项目资助

摘　　要：通过对饱和砂岩和大理岩的循环载荷实验,本文研究了应力—应变曲线的细微差异,指出对于不同孔隙流体和不同性质的岩石,其应力—应变滞后回线的形状是不同的。这是由这些岩石在循环载荷下应变相对应力的响应不同造成的,在加载阶段应变的相位可能超前、并行或者落后于应力的相位。本文引入了Preisach-Mayer-goyz模型(简称PM模型),并对这种现象进行了模拟。通过构筑PM空间密度函数,求出饱和岩石的应力—应变状态方程,并模拟了其轴向应变—径向应变滞后回线。根据模拟结果可以认为,PM空间中不同的密度函数在一定程度上反映了饱和岩石在地震波载荷作用下的本构关系响应的不同性质。Through cycling loading experiment for saturated sandstone and marble and studying the subtle difference in their stress-strain curves, the paper pointed out that the hysteresis loops of stress-strain has different shapes for rocks with different characters and saturated with various pore-fluids. These differences are caused by different responses of strain on stress when rocks are under cycling load, which the phases of strain may be leading, lacking and lagging of stress phases in loading stage. The paper introduced Preisach-Mayergoyz model (simplified as PM model) to simulate the phenomenon. Through constitution of PM space density function, the stress-strain state equation for saturated rocks has been defined and the hysteresis loops of axial stress-radial stress has been simulated. The simulated results showed that the different density function in PM space reflects in some degree that the saturated rocks have the different character of relation response under function of seismic wave load.

关 键 词：循环载荷 饱和岩石 应力 地震勘探 地震学 

分 类 号：P631.4[天文地球—地质矿产勘探]