大连地下石油储备库地应力场反演分析

Inversion analysis of initial stress field of Dalian underground oil storage cavern

初始地应力场是地下工程稳定性评价的基础。结合大连地下石油储备库工程,提出一种基于现场地应力实测资料直接反演初始地应力场的新方法。首先,通过现场实测地应力结果的统计分析,建立初始地应力与高程之间的关系;其次,由于主应力的方向与模型坐标轴方向不重合,进行应力变换;最后,基于FLAC3D的FISH语言编写函数,采用Hoek-Brown强度准则,直接反演大连地下石油储备库的初始地应力场。计算结果与实测结果的对比分析表明:直接法反演的初始应力场的拟合度较高,误差较小,可以满足工程的需要。该法是一种切实可行、简单有效的方法。

Initial stress field is the basis of the stability evaluation of underground engineering. In initial stress field analysis of Dalian underground oil storage cavern, based on site stress test data, a new method of inversion of initial stress field is proposed. Firstly, the relationship between initial stress field and elevation is established according to the analysis of rneasured stresses. Secondary, because the direction of principal stress and model coordinate axis do not coincide, the stress must be transformed. Finally, inversion of initial stress field is completed with functions using the Hoek-Brown rock mass strength criterion. The functions are defined with the programming language FISH embedded within FLAC3D. Through the comparison between calculated stresses and measured stresses, it is shown that the proposed method has higher inversion precision, smaller error and meets the needs of engineering, which reveals that it is a practical, simple and effective method.