New System for Rock Stress Determination by Stress Relief Methods

本项目取得的主要成果如下。(1)理论应力分析结果表明，套芯半径对套芯推进过程中的应变变化特征有一定的影响。由此得到了三种不同取心半径下的理论应变变化特征曲线。(2)采用理论应变变化曲线作为数据库，便于计算机分析。(3)提出了考虑套芯推进过程中应变变化特征的应力解除法岩石应力测定新体系。并在PC机上开发了该系统的程序。(4)将新系统应用于实际资料，结果表明，与常规方法相比，该系统提高了地应力测定的精度。

Main results obtained in this project are following. (1) By the results of theoretical stress analysis, it became clear that strain change characteristics as advancing overcoring is influenced by the radius of overcoring. Therefore, theoretical strain change characteristics curve are obtained correspond to three different radius of overcoring. (2) Theoretical strain change curves are arranged as the data base, so that it is convenient for computer analysis. (3) New system for rock stress determination by stress relief method taking the strain change characteristics as advancing overcoring into account, are proposed. And the programs of this system for personal computer are developed. (4) New system is applied to actual data, and it is confirmed that the accuracy of rock stress determination is improved comparing with the conventional method.