水下盾构隧道管片衬砌结构渐进性破坏机理研究

发布时间：2018-04-12 19:16

本文选题：盾构隧道 + 衬砌结构　；参考：《西南交通大学》2015年硕士论文

【摘要】：目前,盾构法已经成为城市地铁、跨越江海等大型隧道的主流施工方法,其结构的稳定性越来越受到人们的重视。大量盾构隧道,尤其是水下盾构隧道管片衬砌结构在建成一段时间以后(甚至刚刚建成不久),便在一种损伤状态下进行工作,管片衬砌结构问题愈发凸显,对结构的安全性提出了挑战,水下盾构隧道结构已逐渐成为国内外研究的热点。论文依托国家自然科学基金项目,结合武汉地铁2号线越江盾构隧道、广深港客运专线狮子洋盾构隧道、武汉三阳路盾构隧道等具体工程,采用相似模型试验与abaqus扩展有限元相结合的研究手段,系统研究了盾构隧道管片衬砌结构渐进性破坏机理、破坏过程以及不同因素对水下盾构隧道管片衬砌结构的渐进性破坏特性的影响规律。通过本文的研究工作,主要得到以下结论：1)综合分析管片衬砌结构的位移及声发射信息,将大型盾构隧道管片衬砌结构渐进性破坏过程分为初始弹性阶段、局部损伤阶段、宏观破坏阶段和整体失稳阶段四个阶段;2)通过对管片衬砌结构上关键点位移随荷载变化曲线的分析,探明了盾构隧道管片衬砌结构失稳临界点,并以关键点位移与隧道外半径比值的形式给出了失稳临界建议值；依据试验数据分析了管片衬砌结构的拼装方式、封顶块位置、所处地层侧压力系数、不同水压以及地层缺陷位置等因素的变化对该比值的影响规律；3)通过对相似模型试验管片衬砌结构破坏发展过程及最终破坏形态的分析,得出导致管片衬砌结构最终失稳的主要因素；4)依据试验数据分析了管片衬砌结构所处地层侧压力系数、拼装方式、封顶块位置、不同水压以及地层缺陷位置等因素的变化对管片结构力学特征和破坏形态的影响；5)在数值计算中引入扩展有限元来研究管片衬砌结构破坏特性,为了满足扩展有限元的的要求,提出了简化接头的处理办法,讨论了折减刚度折减系数用λ接头折减区域圆心角φ的选取依据；对不同工况下管片衬砌出现裂缝时刻所对应的拱顶、拱底的应力和位移作了对比分析；对不同工况下管片衬砌裂缝的分布和扩展作了对比分析。
[Abstract]:At present, the shield method has become the mainstream of city subway, construction method and other large span Jianghai tunnel, the stability of the structure more and more attention. A lot of shield tunnel, especially underwater shield tunnel lining structure after the completion of a period of time (or even just completed soon, will work in) an injury under the condition of the increasingly prominent problem of segment lining structure, presents a challenge to the safety of the structure, the underwater shield tunnel has become a hot research at home and abroad. Based on the National Science Foundation project, combined with the Wuhan Metro Line 2 of the shield tunnel, Guangzhou Shenzhen Hong Kong passenger Shiziyang shield tunnel, concrete Wuhan Sanyang road tunnel, using the similar model test and ABAQUS extension of finite element method combined with the system of segment lining of shield tunnel machine progressive failure Daniel, the failure process and influence factors of lining structure of shield tunnel segment under water progressive failure are investigated. Through this research, the main conclusions are as follows: 1) the comprehensive analysis of displacement and acoustic lining structure of transmitting information, the large shield tunnel lining structure progressive failure process is divided into initial the elastic stage, the local damage stage, macroscopic failure stage and the overall instability of the four stage; 2) through the analysis of the displacement of key points on the segment lining structure changes with the load curve, proved the segment lining of shield tunnel critical point of instability, and with the key point displacement and tunnel radius ratio is given in the form of lost critical advice value; on the basis of test data analysis of the assembling segment lining structure, cap block position, the formation of lateral pressure coefficient, different water pressure and formation defect position etc. The change of the factors which influence the ratio; 3) based on the analysis and the final failure mode similar model test of segment lining structure damage development process, it is concluded that the final lining structure of major factor for instability; 4) on the basis of test data analysis of segment lining structure for the stratum lateral pressure coefficient, assembling method, block cap influence of different position, pressure and other factors on the formation of defect location segment structure of the mechanical characteristics and failure forms; 5) introduced the extended finite element to study the damage characteristics of lining structure in numerical calculation, in order to meet the requirements of the extended finite element method, puts forward solutions to simplify joint stiffness reduction, is discussed the reduction coefficient for lambda joint reduction center angle region according to different working conditions; the lining cracks appear corresponding moment in the vault, the stress and displacement of the arch bottom The comparative analysis is made on the distribution and expansion of the cracks in the lining of the pipe lining under different working conditions.

【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U457.2

【参考文献】