基于正交设计的地下水封洞库群优化

Based on orthogonal design to optimize water sealed underground oil storage caverns

大型地下水封石洞油库是目前国内外石油战略储备的重要方式,为保证该类大断面不支护地下洞室群的稳定,需优化洞室群的布置。在分析山东某地下水封洞库群工程地质条件的基础上,建立洞室群数值模型。根据三轴试验、围岩RMR(rock mass rating)分类和广义Heok-Brown准则估计了II、III和IV类围岩的岩体力学参数。以洞室埋深、轴向和间距为因素,采用正交设计的方法进行数值试验,以关键点位移和塑性区面积作为评价指标对试验结果进行直观分析,得到对洞室围岩变形和塑性区面积影响最显著的为洞室轴向,并研究了轴向对围岩变形和塑性区面积的影响,得到该水封洞库洞室群的最优布置方案为埋深-60.0 m,轴向N30°W,间距为25 m。其研究结果对地下水封洞库洞室群的布置具有一定工程意义和理论价值。

Storing oil in large underground caverns by water sealed is an important way of strategic oil reserve in the world.It needs to optimize the layout of caverns for the stability of such a large-scale unlined underground cavern.Based on the analysis of the engineering geological characteristic of an underground project in Shandong province,the numerical model was established.And the mechanical parameters of rock mass were estimated by the generalized Heok-Brown failure criterion with the integration of rock sample triaxial test and rock mass classification of rock mass rating（RMR） system.Choosing the depth,axial direction and space as factors,and calculated the displacement of the caverns by the FLAC3D code in different schemes,determined by the orthogonal design.The visual analysis of the results of the evaluating index,key point displacement and plastic zone area was done.The axial direction is the significant factor,and the influence on the stability was studied separately.The optimized layout of the underground caverns is that the depth is-60.0 m,axial direction is N30°W and space is 25 m.It has some values for the layout of the underground oil storage caverns.