利用四元件钻孔应变观测资料研究佘山地区主应变及主方向变化特征

为研究佘山地区应变场变化特征，采用“钻孔加衬模型”公式，使用2013~2018年佘山台观测资料的变化值及差分值，通过无校正、变化校正和差分校正3种应变换算方法，得到3组面应变年速率、最大剪应变年速率变化及应变主方向计算结果。对比发现，利用差分值进行应变换算，在计算应变主方向及提取面应变年速率和最大剪应变年速率特征曲线方面更有效。

On Variation Characteristics of Main Strain and Main Direction in Sheshan Area Using Four Element Borehole Strain Observations

In order to study the variation characteristics of strain field in Sheshan area, three sets of annual strain rate, maximum shear strain rate and their responses are obtained using the borehole-lined model formula, the variation and difference values of observed data from 2013 to 2018 of Sheshan station, and three strain conversion methods, including no correction, change correction and difference correction. Three sets of surface strain annual rate, maximum shear strain annual rate change and strain main direction calculation results were obtained.It is found that the difference value is more effective in calculating the main direction of strain and extracting the characteristic curves of annual strain rate and maximum shear strain rate.