防渗保温衬砌结构稳定性研究

发布时间：2018-11-01 10:48

【摘要】：南水北调工程宝郏段位于南水北调工程中线工程的河南省境内。宝郏段的衬砌结构采用了特殊的防渗保温结构，其中，喷砂加糙保温板提高了衬砌结构的抗冻性，改善了渠道在低温下的工作条件；复合土工膜提高了输水效率。但是，由于这种新型结构的材料属性复杂，接触层面较多，加上复杂的自然与地质因素，整体结构的稳定性有必要要进一步深入研究。本文以南水北调工程宝郏段位渠道衬砌为研究对象，自下而上分别对渠道衬砌结构的各个组成部分进行了分析。通过瑞典条分法和ANSYS数值模拟，分析了渠道边坡和衬砌土体的稳定性，，结果表明，1:2的边坡具有足够大的安全系数，能满足工程稳定的需要；研究了保温板在结构中的作用，热稳态分析与热瞬态分析均证明，保温板在控制热量传递中具有较大作用，并通过热量分度云图的温度等值线对保温板的厚度选择进行了优化；数值模拟表明，对于混凝土层无论是在自然状态下还是在冻胀的状态下，衬砌的坡脚与齿墙接触部分都是应力集中现象最明显的部位，有必要对齿墙结构进行优化设计；建立了冻胀作用下混凝土层受力模型，计算了其在特定环境下弯矩的分布，发现衬砌板的距下边1/4处弯矩最大。最后，以室内摩擦试验结果和数值模拟为基础，分析了渠道衬砌结构中可能出现滑移的原因。
[Abstract]:The treasure section of the South-to-North Water transfer Project is located in Henan Province, the middle route of the South-to-North Water transfer Project. The lining structure of Baoji section adopts special anti-seepage and heat preservation structure, among which, sand blasting and rough insulation board improve the frost resistance of the lining structure, improve the working conditions of the canal at low temperature, and the composite geomembrane improves the water transfer efficiency. However, the stability of the whole structure should be further studied because of its complex material properties, more contact layers and complicated natural and geological factors. This paper takes the channel lining of Baojiazhang Section of South-to-North Water transfer Project as the research object, and analyzes each component of the channel lining structure from the bottom to the top. The stability of channel slope and lining soil is analyzed by Swedish slice method and ANSYS numerical simulation. The results show that the 1:2 slope has enough safety factor to meet the need of engineering stability. The function of thermal insulation board in structure is studied. It is proved by thermal steady state analysis and thermal transient analysis that thermal insulation board plays an important role in controlling heat transfer, and the thickness selection of thermal insulation board is optimized by the temperature isoline of heat index cloud diagram. The numerical simulation shows that the contact part between the slope foot and the tooth wall of the lining is the most obvious part of the stress concentration, so it is necessary to optimize the design of the tooth wall structure. The stress model of concrete layer under frost heaving is established, and the bending moment distribution in specific environment is calculated. It is found that the bending moment of lining slab is the largest at 1 / 4 below. Finally, based on the results of indoor friction test and numerical simulation, the possible causes of slip in the tunnel lining structure are analyzed.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV672;TV543

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