【摘要】 岩体参数是岩体工程设计与优化的重要依据。以现场精细结构测绘为基础,借助数值计算工具,进行大样本岩体力学试验为岩体参数的确定提供了一种新思路。精细结构描述的重点在于现场地质测绘工作的细致。以统计窗为基础,结合地质素描和数码摄像技术,补充发展了一套岩体精细结构测绘的现场工作方法。以现场测绘为基础,建立岩体结构模型。同时,通过离散元数值试验与物理模型试验的对比,验证数值试验的精度,并以锦屏一级水电站为例对坝区岩体进行大样本岩体数值试验,给出应力–位移全过程曲线、应力分布、位移分布及塑性区分布等分析成果。对比发现,数值试验结果与岩体质量评价结果基本吻合,计算结果可靠。数值试验细化了岩体参数的分布特征,大样本试验将会促进工程参数风险预测和可靠度分析的发展。更多还原

【Abstract】 The effects of fracture,joints and other inter-block gaps on rock mechanical properties can be very significant.A method based on site investigation and numerical test is conducted to determine and optimize the mechanical properties for engineering design.Contrasting with field experiment,it is convenient,fast and cheap.The method makes it possible to develop large sample rock mass in-situ tests,which will make a big push for the parameter risk prediction and reliability analysis of engineering rock masses.The research mainly includes two parts of work,i.e.the in-situ fine structure description and numerical test.Engineering geology information which is the input for numerical test is the base of the analysis.Detailed geological investigation is the soul of the fine structure description.Based on statistical window,geological sketch and digital photography,a new method for rock mass fine structure in-situ mapping is developed.It has already been taken into practice and has received good comments in Jinping First Stage Hydropower Station.After obtaining the basic geological information,the rock mass structure model is established through the in-situ mapping.In order to verify the validity and precision of the numerical analysis,a physical model direct shear test is carried out.According to the comparison,the relative error between the numerical test and the physical test is less than 10%.It is precise enough for rock mass mechanical parameter determination.Taking the Jinping First Stage Hydropower Station for example,large sample numerical experiments are carried out in the dam site.The complete stress-displacement curve,stress distribution,displacement distribution and plastic zone distribution are given by the numerical test.By comparison,the results obtained from numerical experiment and those from rock mass evaluation are marched well.更多还原