HOEK-BROWN强度准则的参数取值研究及其工程应用

发布时间：2018-09-09 13:23

【摘要】：随着经济和社会不断发展,我国地下工程建设日新月异,地铁隧道、深部矿山等地下工程建设在全国迎来新的高峰期。这给岩体力学发展带来空前的机遇,也给岩土工程工作者带来了更加严峻的挑战。如何准确获得岩体力学参数便是其中一个十分棘手的问题。本文针对岩土工程中的Hoek-Brown (H-B)强度准则,结合其表达形式及准则岩体参数现有的选取方法,提出两种新的H-B准则参数的确定方法。主要研究内容如下:(1)基于H-B强度准则,利用微震监测资料确定岩体的力学参数,提出基于微震监测的GSI取值方法,该法可以较好地获取复杂条件下的岩体力学参数。此外,借助FLAC软件自带的FISH语言开发平台,开发出等效Mohr-Coulomb(M-C)计算模型,为复杂问题的分析提供了数值依据,并用于分析塔山特厚煤层8103工作面的围岩应力场及采空区上覆岩层移动规律,取得了理想效果。(2)采用正交设计敏感性分析方法讨论H-B准则4个参数的敏感性,分析结果表明,敏感性排序依次为:地质强度指标GSI,扰动系数D,单轴抗压强度σci,完整岩石材料参数mi。其中,GSI对隧道周边位移值有高度显著影响,D对隧道周边位移有显著影响,mi、σci对隧道周边位移值影响很小,不显著。(3)结合敏感性分析结果及H-B准则的圆形硐室围岩位移表达式,借助数值模拟计算和回归性分析建立了基于H-B准则的位移非线性回归模型,并结合差分进化算法制定合理的优化反分析方法及步骤,该方法克服了智能优化算法运行过程中反复调用FLAC3D软件造成的运算时间过长等问题。(4)结合青岛地铁一期工程3号线监测资料,借助均匀设计及FLAC3D软件确定该工程的基于H-B准则的位移非线性回归模型系数,并验证了该回归模型符合精度要求,进而采用本文建立的位移反分析方法对该地区10个工况进行岩体参数反演研究,取得了良好的效果。结合青岛地铁项目声波测试数据,拟合GSI与岩体纵波波速Vp的关系式,并验证了关系式的合理性。
[Abstract]:With the continuous development of economy and society, the construction of underground engineering in our country is changing with each passing day. The construction of underground engineering, such as subway tunnel, deep mine and so on, has ushered in a new peak period in the country. In this paper, two new methods for determining the parameters of H-B criterion are proposed based on the strength criterion of Hook-Brown (H-B) in geotechnical engineering and the existing methods for selecting the parameters of the criterion rock mass. In addition, the equivalent Mohr-Coulomb (M-C) calculation model is developed by using the FISH language development platform of FLAC software, which provides a numerical basis for the analysis of complex problems and is used to analyze the 8103 thick coal seam in Tashan. The stress field of surrounding rock in working face and the movement law of overlying strata in goaf have achieved ideal results. (2) The sensitivity of four parameters of H-B criterion is discussed by using the sensitivity analysis method of orthogonal design. The results show that the order of sensitivity is GSI, disturbance coefficient D, uniaxial compressive strength_ci and complete rock material parameter mi. GSI has a highly significant effect on the surrounding displacement of the tunnel, D has a significant effect on the surrounding displacement of the tunnel, mi, _ci has little effect on the surrounding displacement of the tunnel, not significant. (3) Based on the sensitivity analysis results and H-B criterion, the displacement expression of the surrounding rock of the circular chamber is established by numerical simulation and regression analysis. Nonlinear regression model and differential evolution algorithm are combined to formulate a reasonable back analysis method and steps for optimization. This method overcomes the problem of too long operation time caused by repeated invocation of FLAC3D software during the operation of intelligent optimization algorithm. (4) Combined with the monitoring data of Qingdao Metro Line 3, uniform design and FLAC3D software are used to determine the optimal back analysis method. The nonlinear regression model coefficients of displacement based on H-B criterion are verified to meet the accuracy requirements, and then the back analysis method of displacement established in this paper is used to inverse the rock mass parameters under 10 working conditions in this area, and good results are obtained. The relation between longitudinal wave velocity Vp and the rationality of the formula are verified.
【学位授予单位】：山东科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU45

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