【作者】 曹冠华；

【导师】 张强勇；

【作者基本信息】 山东大学 ， 岩土工程， 2013， 硕士

【摘要】 这些年来,深部地下洞室工程在地下工程中所占的比重越来越大,对于深部洞室中的各种岩石破裂现象的研究也有了新的发现。在高地应力,高温,大扰动等复杂情况下,深部岩体破坏出现了与浅部岩体截然不同的破坏现象,其中,分区破裂现象十分引人关注。本文结合国家自然科学基金项目,以淮南矿区丁集煤矿深部巷道为工程背景,基于模型试验相似理论,依托自主研制的大型真三维地质力学模型试验系统,通过多个不同工况的地质力学模型试验研究不同洞室形态、不同地应力加载方向和含有夹层等因素对分区破裂破坏模式的影响,对研究分区破裂的影响因素及形成机制有十分重要的意义。本文的研究工作和相关结果如下：(1)自主研制了高地应力真三维加载模型试验系统,最大压力加载值为31.5Mpa,可用于同步、独立地向模型施加三轴高地应力。(2)开展了预留洞室轴向压缩破坏的模型试验,发现轴向高地应力下的洞室围岩出现了多条间隔破坏线,验证了轴向高地应力是导致产生分区破裂的重要因素。(3)在圆形、城门洞形、矩形等不同洞形条件下进行模型试验,均再现了分区破裂现象。得出：在动力开挖下,初始最大主应力平行于洞轴方向且其量值超过1.5倍围岩的抗压强度是深部洞室围岩产生分区破裂的重要条件；分区破裂纵向裂纹与巷道轴线基本平行；分区破裂的范围与洞形和洞室尺寸密切有关,洞室尺寸越大,分区破裂范围就越大；分区破裂形状与洞形无关,在不同洞型条件下,围岩分区破裂最外边界的形状均为近似的圆形；相邻两破坏区的平均半径之比在1.3-1.4之间,基本符合(?)的模数关系,即ri=(?)(i=1,2,3,4),其中i为破裂区的编号,r0为巷道的半径或宽度。(4)试验得到含有夹层的模型在动力开挖且平行于洞轴方向的初始最大主应力超过1.5倍围岩的抗压强度时会出现分区破裂。(5)通过初始最大主应力平行和垂直洞轴方向条件下的模型试验,发现初始最大主应力垂直于洞轴向时,模型出现塑性松动圈破坏区,不会出现分区破裂现象。(6)基于应变能密度理论进行数值模拟,成功再现了分区破裂现象。数值模拟中的分区破裂破裂区范围、破裂区层数、最大破坏范围与洞径比值与模型试验结果基本相同；数值模拟中洞周位移变化规律与模型试验测得规律基本相同,呈现波浪形变化。更多还原

【Abstract】 Over the years, the proportion of deep underground cavern project in underground engineering is growing, there are some new discoveries of rock fracture phenomena in the deep tunnel. In the complex case of the high stress, high temperature, large disturbance conditions, the deep rock mass destruction appeared distinct from the shallow rock breakage, which zonal disintegration phenomenon is very interesting. This paper supported by the National Natural Science Foundation of China, taking the Huainan mining area Dingji deep mine roadway as background, based on similar principles of model test, relying on independently developed large-scale three-dimensional geomechanical model test system,taking geomechanical model tests in the different cavern shapes, stress loading directions and geological conditions that is very important to influencing factors and formation mechanism of zonal disintegration. In this paper, the research work and related results are as follows:(1) The self-developed high geo-stress true3D loading model test system can be used to apply triaxial high stress synchronization and independently, the maximum pressure is31.5Mpa.(2) Through the model test of the axial compression on the cavern obligated, it is found that the axial high geo-stress is the important factor which lead to the zonal disintegration.(3) Through the model tests in citygate-shaped, rectangular-shaped reproduce the phenomenon of zonal disintegration.Draw that in the of power excavation and the magnitude of initial maximum principal stress parallel to the hole axis direction more than1.5times of the compressive strength of the surrounding rock is the important condition to the zonal disintegration appearing; the longitudinal cracks of zonal disintegration substantially parallel to axis; the range of the zonal disintegration relates to the hole shapes,caverns size,the longer of the cavern diameter or width, the greater ranger of the zonal disintegration; The zonal disintegration independent of the carven shapes, the outermost boundary are approximated circular shapes in zonal disintegration;the average radius ratio of the two adjacent destruction between1.3～1.4, in line with (?)2modulus relationship,that ri=(?)2ri-1(i=1,2,3,4),i is the number of the rupture zone, r0is the radius or width of the cavern.(4) When the test model containing interlayers in the of power excavation and the magnitude of initial maximum principal stress parallel to the hole axis direction more than1.5times of the compressive strength of the surrounding rock,the phenomenon of zonal disintegration appears.(5) Through initial maximum principal stress parallel and perpendicular to the hole axis direction model test and found that when the initial maximum principal stress vertical axial hole, the model plastic loose circle of damage zone appears, which does not appear the phenomenon of zonal disintegration.(6) Based on the strain energy density theory successfully reproduced the phenomenon of zonal disintegration with numerical simulation. In the numerical simulation of zonal disintegration, the rupture area, rupture zone layers, ratio of the maximum extent of damage with the hole diameter are basically same with the model test results; the displacement variation in numerical simulation with model test measured law is basically the same, showing changes in the wavy.更多还原