双江口水电站初始地应力场反演回归分析

Back regression analysis on the initial geostress field of the Shuangjiangkou hydropower station

初始地应力是岩土工程设计与施工所要考虑的重要因素之一.根据双江口水电站工程区域实际地质条件以及实测地应力资料,建立了能够反映研究区地貌、岩体结构的地质模型.采用快速拉格朗日计算程序FLAC3D对建立的三维地质概化模型进行计算,在实测点地应力值与计算得到的应力值之间建立多元回归模型,通过多元回归分析,求出最优回归系数.通过实测点的计算应力值与现场实测值的比较,两者在量值上相当且方向上接近,表明经过回归得到的地应力场是合理的,为双江口水电站地下厂房的开挖模拟及长期稳定性分析提供了合理的三维初始地应力场.

Initial geostress is indispensable to the design and the construction of rock engineering.Based on the measured data of geostress and engineering-geological conditions in the region of the Shuangjiangkou hydropower station,a geological model was developed to express the physiognomy of the research area and rock mass structure.The established 3D simplified geological model was calculated by fast Lagrangian analysis for the Continuum of FLAC3D.A multivariate regression model was established between the actually measured and corresponding calculated results of geostresses.According to multiple regression analysis,the optimum regression coefficient can be received.Through the comparison between computed and measured geostress values of measuring points,it was found that they are similar in values and directions,which suggests the accuracy and reasonability of the geostress field.The results offer reasonable geostress field for excavating simulation and analysis of the stability of the underground workshop of the Shuangjingkou hydropower station.