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1、第7章 岩体(rock mass),7.1 变形特性(deformability),7.2 强度(strength),代入M-C准则,第8章 岩体分级(rock mass classification),8.1岩体分类(RMR)系统(rock mass rating system),完整岩石的单轴抗压强度(the uniaxial compressive strength of the intact rock); 岩石质量指标(RQD); 非连续面间距(Discontinuity spacing); 非连续面情况(Condition of discontinuity surfaces); 地下
2、水条件(Groundwater conditions); 与工程结构相关的非连续面方向(Orientation of discontinuities relative to the engineered structure).,8.2 Q系统(Q-system),岩石质量指标(RQD); 非连续面组数(number of discontinuity sets); 最不利非连续面粗糙度(roughness of the most unfavourable discontinuity); 最弱非连续面蚀变或填充程度(degree of alteration or filling along the
3、 weakest discontinuity); 裂隙水(water inflow); 地应力情况(stress condition).,RQD=rock quality designation; Jn=joint set number (related to the number of discontinuity sets); Jr=joint roughness number (related to the roughness of the discontinuity surfaces); Ja=joint alteration number (related to the degree
4、of alteration or weathering of the discontinuity surfaces); Jw=joint water reduction number (relates to pressures and inflow rates of water within the discontinuities), and SRF=stress reduction factor (related to the presence of shear zones, stress concentrations and squeezing and swelling rocks),RQ
5、D/Jn与岩体几何结构相关； Jr/Ja与岩块间的剪切强度相关； Jw/SRF是一个“环境因子”(environmental factor),它综合水压力和流动速率、剪应力区的存在、岩体挤压和膨胀，以及原位应力状态等各方面的影响。,8.3岩体分级系统的应用,RMR系统的评分值范围是0100，Q系统评分值范围是0.0011000，根据分级评分值可对岩体进行描述。 两种分级法都是从估计隧道开挖所需支护的土木工程中来的，用于别的工程要慎重。 以下两图为例说明两种方法定量评价岩体，估算隧道的“自稳时间”和支护需求。,Romana（1985）通过考虑以下因素对RMR值进行调整，将分级系统推广应用到边坡工程。 F1与边坡和非连续面走向之间的平行度有关； F2与发生平面破坏的非连续面的倾角有关； F3与对比非连续面倾角和边坡倾角有关； F4与开挖方式有关。,8.4分级系统与岩体特性的关联(links between the classification systems and rock properties),Undisturbed rock: Disturbed rock: Where RMR is the unadjusted rating form the system.,