地表潮汐平面应变状态与地震关系的研究

以河北怀来台三方向伸缩仪为例，根据应变观测平面应变状态的基本理论和计算方法，通过计算得到了应变观测点的最大主应变、最小主应变、主应变方向和剪切应变的变化曲线，结合1989年10月18日山西大同－阳高6．1级地震和1998年1月10日河北张北6．2级地震，对地表平面应变状态与地震的关系进行了深入研究。得出如下结论：地表潮汐平面应变状态与地震存在一定的关系，而且在中强地震前地表潮汐平面应变状态表现出不同的变化特征。

Study on the Relationship between the Strain State of Tide Plane on the Ground Surface and the Earthquakes

Based on the basic theory and principle of the plain strain state observation,the variation curves of the maximum principal strain,minimum principal strain,principal strain orientation and shear strain at the strain observation points are obtained from the threecomponent tensometer on Huailai station,the relationship between the strain state of the tide plane on the ground surface and the earthquakes is discussed combining with the M6 1 Datong Yanggao earthquake on october 18,1989 and the M6 2 Zhangbei earthquake on January 10,1998 The conclusion shows that there is some relationship between the tide plane strain state of the ground surface and the earthquakes,and the tide plane strain state of the ground surface appears varied variation features before the medium strong earthquakes