【作者】 聂林；

【导师】 周德培；

【作者基本信息】 西南交通大学 ， 岩土工程， 2012， 博士

【摘要】 富水花岗岩蚀变带是岭南地区较为常见的一类特殊地质体,因其分布复杂,富含地下水,力学性质特殊,隧道工程通过其分布区时,往往会发生难以控制的围岩大变形以及涌水突泥等工程病害。论文以新建洛湛铁路两处典型工点为例,综合运用现场调查、室内试验、理论分析、数值计算和模型试验等手段,对富水花岗岩蚀变带隧道大变形机理及其施工控制等相关问题进行了全面深入的探讨。(1)通过调查分析,总结了花岗岩蚀变带的时空分布特征和典型工点工程地质条件；开展了相关试验,分析了蚀变岩的矿物成分、物理力学性质,得到了蚀变岩的应力应变关系,掌握了蚀变岩的变形特征；最终得到富水花岗岩蚀变带隧道围岩工程地质特征,为进一步变形机理分析奠定了基础。(2)通过施工变形反演和力学参数反演,得到了符合蚀变岩变形特征的本构模型,即损伤本构模型或SS软化本构模型,从而得到围岩大变形机理的合理解释。建立了概化复杂岩体结构特征的计算模型并进行了数值模拟,分析了隧道与蚀变岩、沉积岩三者间不同的位置关系时隧道的变形收敛特征。(3)提出两种开挖大变形施工控制技术并进行了应用示例。一是考虑围岩内各点不同的稳定性状态,采用基于点安全系数场的开挖松动区分析方法；二是采用动态设计的观点,根据经验并监测分析围岩收敛位移发展规律,判断围岩的变形发展特征,及时一步强支到位。(4)基于流固耦合理论,将广泛应用于边坡稳定性计算的有限元强度折减法引入到开挖面的稳定性分析中,基于安全系数来定量评价开挖面的稳定性,对渗流条件下蚀变带隧道的变形机理和控制措施进行了研究。.得到隧道开挖导致开挖面前方的松动区范围、开挖过程中应贯彻的治水原则以及隧道周边及超前注浆预加固的范围。(5)通过大小比例模型试验,均很好地验证了前面各章节相关理论分析的正确性以及施工现场的实际情况。更多还原

【Abstract】 Alteration rock is a familiar special rock mass at the district of Lingnan, the difficultly controlled large deformation of surrounding rock and water gushing and sudden mud usually occur when a tunnel passes the distribution area of alteration rock due to its complex distribution, water-riched and special mechanical property. Taking the two typical construction sites of the newly constructed Luo-zhan railway as examples, in this paper the research means of field survey, the experiments in the laboratory, theory analysis numerical computation and model test are comprehensive used. The mechanism of the tunnel’s large deformation and the control measurements for the construction in the alteration strip of granite containing rich water are deeply studied.(1)On the basis of survey and analysis, the space-time distribution rule of alteration rock and the engineering geological condition at the typical work site are concluded; the indoor and outdoor experiment are carried out, the mineral ingredient and physical and mechanical property are analyzed, stress-strain relation is also discussed, the deformation characteristic of alteration rock is established. Engineering geological characteristic of the surrounding rock alteration rock is concluded which becomes the test basis for further deformation mechanism analysis.(2)By construction deformation inversion, constitutive model according with altered rock’s deformation features is put forward. That’s damage model or ss softening constitutive model.So reasonable explanation for large deformations of surrounding rocks mechanism is obtained. The calculation model of generalized complex rock mass structure is built up and numerical computation is carried out, tunnel’s deformation convergence characteristic is analysed at different positions relation among tunnel, altered rock and sedimentary rock.(3)Two kinds of control measurements for the construction of the large deformation are put forward as well as be taken into practice.First, the point safety statement of surrounding rock different positions are considered, excavation loose region of zone analysis method based on point safety factor field is employed. Second the dynamic design method is adopted, through the experience and monitoring and analysis of surrounding rock convergence displacement development rule, the surrounding rock deformation characteristics are determined as well as the single-time strong support method to control the latent large deformation of surrounding rock.(4) Based on fluid-solid coupling theory, strength reduction FEM widely used in the calculation of slope stability is introduced into the excavation face stability analysis, based on the safety coefficient to quantitative evaluation of the excavation face stability, deformation mechanism and control measures of the alteration rock’s tunnel under the seepage condition are studied. The range of loose region in front of the excavation face is obtained as well as the principle of water control methods which should be carried out in the process of excavation, the reinforcement scope of tunnel perimeter and advanced pre-grouting is also determined.(5) By the size ratio model test, the correctness of the preceding chapters related theoretical analysis and actual conditions of construction field are well corroborated更多还原