空心包体式钻孔三向应变计测试技术探讨

Measuring techniques for hollow inclusion triaxial strain cells

探讨了澳大利亚CSIRO型空心包体式钻孔三向应变计的测量技术,重点介绍了测量元件应变片的布置形式和利用围压加载试验成果修正原始解除应变实测值的方法。对解除应变实测值的修正提出了具体方法,由修正后的解除应变推算的地应力实测值更精确。在三峡工程永久船闸开挖完成后岩体应力动态变化测量中,具体分析了测量元件应变片黏贴部位和角度的误差所引起的地应力实测值的误差,具体实施了对解除应变实测值的修正,实测的岩体应力动态变化更符合工程实际情况。

Australia CSIRO hollow inclusion triaxial strain cell possessing many unique merits is one of the most world-wide measuring devices applied for geostress measurements.The measuring technique is discussed.The arranging style of strain gauges and the correcting method used for the measured values of the originally relieved strains by confining pressure tests are introduced.The concrete correcting method of the measured values of relieved strain is advanced,and the measured geostress values calculated by the relieved strains after correction are more accurate.In the dynamic changing measurement of rockmass stress after excavation of the permanent ship-lock of the Three Gorges Project,the errors of the measured values of geostress caused by the errors of arranging places and angles of strain gauges are analyzed,and the measured values of the relieved strains are corrected.Based on the corrected strain values,the measured dynamic changes of rockmass stress are better in accordance with the practical engineering state.