【作者】 陈陆望；

【导师】 白世伟；

【作者基本信息】 中国科学院研究生院（武汉岩土力学研究所） ， 岩土工程， 2006， 博士

【摘要】 物理模型试验比较直观,可定性或定量反映与地下工程有关的天然岩体受力特性,和与其相联系的地下工程结构的相互影响,能真实地模拟复杂地下工程结构、复杂地质构造、复杂地下岩层组合关系,等等。随着新建地下工程规模越来越大,出现的问题越来越复杂,需要研究的内容越来越多,使得物理模型试验越来越具有实际的工程意义。本文是在遵循相似理论的基础上,着重从模型试验技术研究方面入手,组织安排开采倾斜近地表矿体地表及围岩变形的平面应力模型试验和高地应力条件下坚硬脆性围岩洞室周边应力分布及围岩变形与破坏的平面应变模型试验,并用相关数值计算软件进行模型试验结果的对比分析。主要研究内容如下:(1)采用Fe3O4粉末、标准石英砂、石膏、水等原材料配制模型材料密度大,通过改变模型材料中石膏的含量,可以使模型材料的抗拉强度在0.0018～0.0180 MPa范围内变化,内聚力在0.0013～0.0700MPa范围内变化,该模型材料适合模拟考虑重力场的岩体;(2)选取单轴抗压强度(σc)、脆性系数(K)与冲击能量指数(WB)为脆性岩体具有岩爆倾向性的概化指标,找出了由石英砂、石膏、水泥、水等配制成的模型材料的σc、K、WB与各原材料成分配比的关系,选取了合适的脆性岩体物理模型材料的配方;(3)对岩土工程大型真三轴物理模型试验机进行电液伺服控制程序二次开发,形成各种不同应力状态、应力路径的控制系统,并反复调试物理模型试验机的试验性能直至满足试验要求;(4)以铜矿矿山一典型地质剖面为原型,运用物理概化模型试验,采用相关的模型试验技术,分析了开采倾斜近地表矿体地表及围岩变形与陷落机理;(5)根据岩土工程大型物理模型试验机应用需要,研制了一套浇注地下洞室物理模型技术,平面应变条件控制技术,洞室围岩应变测试技术和围岩破坏全过程内窥摄影技术,并开展了坚硬脆性围岩洞室在不同边界荷载条件、不同断面形状的平面应变模型试验,分析了围岩应力分布特征及变形破坏过程及机理等;(6)根据物理模型试验的结果,开展物理模拟与数值模拟对比分析。更多还原

【Abstract】 Physical model test is intuitionistic and can qualitatively or quantitatively reflect the mechanics trait of crude rock-mass and interaction among complex engineering structures in underground engineering. Furthermore, it can simulate complex engineering structure, geologic conformation, stratum combination and so on of the underground engineering. Model test is more and more of real engineering significance with more and more great underground engineering being constructed and more and more complex problem appearing and more and more study content needing to be solved. Based on the similarity theory, proceeding with model-test technology, plane stress model test on deformation and subsidence of ground surface and surrounding rock caused by exploiting inclining mine near surface and plane strain model test studying the stress distribution and transmogrification and breakage of rigid brittle surrounding rock under the condition of high-stress are done. In addition, the result of physical model test has been contrasted that of numerical analysis. The main studying content is listed below:(1) The model material, which density is over 27KN/ m3, is made from powdery Fe3O4, powdery quartz grit, gesso, water and so on. The content of gesso being adjusted in this kind of model material,the tensile strength of standard sample with it can range between 0.0018～0.0180 MPa, the cohesion strength can range between 0.0013～0.0700MPa MPa. Therefore, the material adapts to simulating rock-mass considering gravity field.(2) Rigid and brittle rock trends to rockburst,which is generalized by uniaxial compressive strength(σc), brittleness coefficient (K) and exponential of strike energy (WB). When developing the similar material of rigid and brittle rock, some ingredient such as quartz grit, gypsum, cement, water, et al is blended by different proportion. From the results of the proportioning test, it is found out that the different proportion of these ingredient influencesσc, K and WB differently. In physical simulating test,σc, K and WB are checked in general and the directions for the material generalization are confirmed. The mechanical parameters of materials by the selected direction not only meet with requests for rockburst, but also are convenient for making large physical models.(3) The servo-control program of the triaxial model-test large machine in geotechnical engineering is redeveloped, so that the program can control different stress conditions and stress paths. The machine has been debugged repeatedly until it meets the demand of physical model test.(4) Based on the antetype of the representative geological section of a copper mine, the physical general model test is done and the deformation law of surrounding rock and the subsidence law of ground surface caused by exploiting inclining mine near surface are discovered.(5) In order to apply the triaxial model-test large machine better in geotechnical engineering, a series of model-test technologies, such as casting technology of physical model, plane strain control technology, the strain measure technology and full inner-spy photography technology in breakage process, are developed. Moreover, applying these technologies, several cavern models of different section shapes simulating rigid brittle surrounding rock are made and tested under different load conditions so that deformation and breakage mechanism and the stress distribution character of surrounding rock are analyzed efficaciously.(6) Contrasting analysis of physical and numerical simulation has carried out on the basis of the results of physical model test.更多还原