环锚无粘结预应力混凝土衬砌隧洞在线监测及安全评价研究

发布时间：2018-03-27 22:14

本文选题：水工结构　切入点：安全评价　出处：《天津大学》2014年硕士论文

【摘要】：水工隧洞是水利水电工程中最常见的引水建筑物，，主要用于泄洪、引水发电、输水灌溉、排泄水库泥沙、导流等。环锚无粘结预应力混凝土衬砌结构近年来作为一种新型结构被逐渐应用于水工隧洞中。它是一种能充分发挥预应力结构特性的新型结构形式，主要适用于压力水头较高、围岩厚度较薄或围岩地质条件较差、衬砌开裂后可能导致重大事故的水工隧洞工程。目前我国已有多个大型水利工程采用这种衬砌结构形式，如清江隔河岩水电站引水发电隧洞、天生桥引水发电隧洞、南水北调工程穿黄隧洞、小浪底工程排沙洞和辽宁大伙房水库引水工程的输水隧洞等。与其他水工隧洞结构形式相比，环锚无粘结预应力混凝土衬砌隧洞具有许多突出优点。但作为一种新型结构形式，他的安全性及可靠性问题是制约其得以普遍应用的关键。本文基于我国首例采用无粘结预应力混凝土衬砌的水工隧洞——小浪底排沙洞工程，对于工程自1999年6月投入运行以来至今十几年的大量监测数据进行分析。获得了针对此类结构监测断面的布置方法、监测数据的分析方法以及各监测仪器受不同因素影响的影响因子。由此确定了环锚无粘结预应力混凝土衬砌隧洞在运行期的运行状态及结构可靠性的安全评价方法，得出了衬砌结构的安全预警值。通过以上分析也同时表明：经过十几年的运行，在各种未知环境作用下，小浪底环锚无粘结预应力混凝土衬砌隧洞并未发生开裂、渗漏、钢绞线断裂或松弛等影响其可靠性的安全隐患，衬砌混凝土绝大部分处于受压状态。环锚无粘结预应力混凝土衬砌结构安全可靠。同时以小浪底实际工程作为实例进行安全评价分析研究，既能对安全评价方法的研究成果进行验证，也可以对今后类似工程的安全监测仪器布置作出指导，对环锚无粘结预应力混凝土衬砌结构的安全评价实施提供明确的步奏参考和数据资料。
[Abstract]:Hydraulic tunnels are the most common diversion structures in water conservancy and hydropower projects. They are mainly used for flood discharge, water diversion and power generation, water conveyance and irrigation, and sediment discharge from reservoirs. As a new type of structure, ring anchor unbonded prestressed concrete lining structure has been gradually used in hydraulic tunnel in recent years. It is a new type of structure which can give full play to the characteristics of prestressed concrete structure. It is mainly suitable for hydraulic tunnel projects with high pressure head, thin wall rock thickness or poor surrounding rock geological conditions, which may lead to serious accidents after lining cracking. At present, this kind of lining structure form has been adopted in many large water conservancy projects in China. For example, the diversion tunnel of Geheyan Hydropower Station in Qingjiang, the Tianshengqiao diversion tunnel, and the tunnel through the Yellow River in the South-to-North Water transfer Project, The drainage tunnel of Xiaolangdi Project and the diversion tunnel of Liaoning Dahuofang Reservoir. Compared with other hydraulic tunnel structures, the ring anchor unbonded prestressed concrete lining tunnel has many outstanding advantages, but as a new type of structure, the tunnel has many outstanding advantages. His safety and reliability are the key to its universal application. In this paper, based on the first case of hydraulic tunnel with unbonded prestressed concrete lining in China, the Xiaolangdi sand discharge tunnel is constructed. A large number of monitoring data from June 1999 to ten years since the project was put into operation have been analyzed, and the layout method for the monitoring section of this kind of structure has been obtained. The analysis method of monitoring data and the influence factors of different factors on the monitoring instruments are given. The safety evaluation method of the running state and structural reliability of unbonded prestressed concrete lining tunnel with annular anchor during operation period is determined. The safety warning value of lining structure is obtained. Through the above analysis, it is also shown that after more than ten years of operation, under the action of various unknown environments, no cracking and leakage occurred in Xiaolangdi ring anchor unbonded prestressed concrete lining tunnel. The safety hidden danger which affects the reliability of steel strands such as fracture or relaxation of steel strands, Most of the lining concrete is in the state of compression. The ring anchor unbonded prestressed concrete lining structure is safe and reliable. At the same time, the actual project of Xiaolangdi is taken as an example to carry out safety evaluation and analysis. Not only can the research results of safety evaluation methods be verified, but also the safety monitoring instrument arrangement of similar projects can be guided in the future. It provides a clear reference and data for the safety evaluation of ring anchor unbonded prestressed concrete lining structure.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV554;TV544

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