四川锦屏山隧道岩爆综合防治施工技术

锦屏山隧道工程是锦屏水电枢纽工程的关键性控制施工项目,隧道地处我国西南高地应力区,全长约17.5km,隧道最大埋深约为2375 m,埋深大于1500 m的地段长度约12875 m。通过对锦屏山隧道现场岩爆特征的分析总结和研究,介绍了锦屏山隧道岩爆独特的工程特点和综合防治施工技术。     

综合地质超前预报在齐岳山隧道施工中的应用

在长大隧道施工过程中,由于工程地质条件的复杂性和不确定性,常会出现如塌方、涌水等地质灾害,为了规避这些地质灾害的发生,在施工过程中实施综合地质超前预报就显得十分有必要。本文以宜(昌)—万(州)铁路齐岳山隧道PDK366+020~PDK365+984段为实例,详细介绍地质分析-TSP地震勘探-超前水平钻探相结合的综合地质超前预报方法,结果证明,该方法具有较高的精度和准确度。     

Numerical simulation for settlement urban tunnel construction

The excavation for the municipal tunnel will disturb the soil around the tunnel, and the deformation and subsidence of the earth surface always take place, which may lead to instability and even collapse for the building above the tunnel. At the same time the deformation and subsidence of the earth surface affect the normal use of underground municipal pipelines, and may cause the road sudden collapse, leading to significantly traffic accidents. The authors did a research by simulating for the excavation of municipal tunnel and designed the related supporting plan, and put forward some suggestions and measures for the design and construction of urban tunnel.     

隧道涌水量的类型划分及预测方法

根据工程应用的目的不同将隧道的涌水量划分为施工涌水量和长期涌水量,针对涌水量预测方法常常存在使用不当的问题,在全面分析隧道涌水量预测方法的适用条件的基础上,按不同的水文地质条件提出了正确选择隧道涌水量预测方法及其计算参数的建议。     

Robust geotechnical design of shield-driven tunnels

This paper presents a fuzzy set-based robust geotechnical design (RGD) methodology for the design of shield-driven tunnels. Here, uncertain geotechnical parameters required for analysis of tunnel performance (referred to herein as the structure safety and serviceability performance of tunnel cross section) are represented as fuzzy sets. Given fuzzy input parameters, the performance of a shield-driven tunnel will be uncertain, which is expressed in this study as a fuzzy factor of safety, according to the analysis of vertex method. Then, the fuzzy factor of safety for a given design is used to evaluate the failure probability and design robustness, which are, in turn, employed in the proposed RGD framework. Note that a design is considered robust if the performance of the shield-driven tunnel is insensitive to the variation of its uncertain geotechnical parameters. Within the RGD framework, each candidate design in the design space is analyzed for its safety state (in terms of failure probability), design robustness, and cost. The goal of the RGD of a shield-driven tunnel is to bring the safety state to an acceptable level, while maximizing the robustness and cost efficiency simultaneously. To this end, a multi-objective optimization is performed and a Pareto front is obtained, which provides a trade-off that may be used to select the most preferred design. Through an illustrative case, the effectiveness and significance of this new robust design methodology is demonstrated.     

Analytical solutions for nonlinear consolidation of soft soil around a shield tunnel with idealized sealing linings

This paper presents the analytical solutions for nonlinear consolidation of soft soil around a shield tunnel with idealized sealing linings. By introducing the empirical relation between permeability and compressibility, along with the conformal transformation, the governing equations of nonlinear consolidation are established, and the corresponding analytical solutions are derived. Then, the Terzaghi consolidation solutions are derived from the degenerate governing equation of nonlinear consolidation. Through the predictions of different consolidation theories in both completely permeable and impermeable lining conditions, the influences of a tunnel acting as a drain and impacting the dissipation of pore pressure, degree of consolidation, long-term ground settlements and ground settlement rates are investigated. During the early stages of consolidation, the case studies reveal that the predictions made by this study strongly agree with the field data when a completely permeable lining is applied. This study confirms that a tunnel acting as a drain can accelerate the consolidation of soil and enlarge soil deformation due to consolidation. During long term consolidation, a notable nonlinearity of the soil consolidation is exhibited by a small and gradually decreasing settlement rate, showing agreement with the tendency of field data from the impermeable conditions.     

南昌地铁二号线隧道开挖风险性可拓学评价

地铁建设中始终面临着隧道开挖风险和毗邻建筑环境的风险,对其进行详细评价并找出主要影响风险源,对于控制工程风险、提高工程安全性和投资效益是地铁工程建设不可忽视的重要环节。应用可拓学方法,分别对南昌地铁二号线翠苑路-地铁大厦区间的隧道开挖风险和毗邻开挖区的建筑环境的风险进行评价,找出了最主要的风险影响因子,对同类工程建设具有借鉴意义。     

地质前探轻便高效钻机的研制与应用

为了确保煤矿井下采掘工作面施工安全,防止因地质条件不清造成安全生产事故,需对施工前方进行地质前探。淮南矿区原来使用的地质前探钻机由于功率太小或搬迁困难,不能很好地满足地质前探钻孔施工需要。以中煤科工集团西安研究院有限公司生产的ZDY1200S型全液压坑道钻机为原型,对其液压系统和主要零部件进行优化设计,以满足地质前探的使用要求。经过现场试验,应用效果良好。     

爆炸地震波作用下盾构隧道动力响应分析

盾构隧道衬砌由于各种类型接头的存在而与整体式衬砌的力学特性存在较大差异。将盾构隧道衬砌结构看作由弹塑性铰链连接的刚性管片组成,考虑围岩介质的黏弹性,提出了爆炸地震波作用下盾构隧道动力分析的简化计算方法。采用该方法对南京地铁盾构段典型横断面进行了动力分析,研究了爆炸地震波入射角度、围岩介质特性及管片厚度对结构受力与变形的影响规律。分析结果表明:波入射角度对盾构隧道有很大影响,斜入射时结构的动力响应要大于垂直入射时结构的动力响应;围岩介质等级越高,围岩对隧道结构的约束越强,隧道的抗爆性能越好;管片厚度的增大会增大结构的内力,合理设置管片厚度有利于提高盾构隧道抗爆性能。     

高铁隧道GPR技术研究与应用

应用基于时间域有限差分法模拟软件GPRMax2D,对高铁隧道衬砌典型的不良情况,如厚度不足、空洞和钢筋布置不合理等进行了正演模拟,得到了隧道衬砌典型不良情况的正演模拟雷达图像。结合某高铁隧道工程实际检测得到的雷达图像,对两者图像作了对比分析,总结得到了隧道衬砌不良情况雷达图像的特征规律,完善了探地雷达图像资料特征解释库,提高了识别高铁隧道衬砌典型不良情况雷达图像的可信度,为高速铁路隧道的无损检测提供了有效的依据。