初始损伤对铁路隧道底部结构力学性能的影响研究

发布时间：2018-04-06 06:28

本文选题：铁路隧道　切入点：底部结构　出处：《昆明理工大学》2017年硕士论文

【摘要】：近年来,随着我国铁路建设的蓬勃发展,运营铁路隧道数量及总里程,以及铁路隧道建设规模和速度已跃居世界第一。在取得巨大建设成就的同时,铁路隧道服役状况不甚理想,运营铁路隧道病害问题日益突出,其中隧道底部病害发生率最高。铁路隧道底部结构的服役性能直接影响列车运营安全,因质量缺陷及基底状况变化等因素,多数隧道底部结构带损伤服役,这严重影响了底部结构使用寿命,造成底部结构破损问题突出。本文针对隧道底部结构病害较为突出的工程现实,采用调查统计、理论分析和数值模拟相结合的方法,从底部结构承载性能和振动响应特征两个方面,系统分析初始损伤对隧道底部结构服役性能的影响规律。主要研究内容如下:(1)基于我国运营铁路隧道典型底部结构病害工程实例的调查统计,从道床类型、底部病害形式、所处水文地质条件以及病害成因等方面,分析了隧道底部结构典型缺陷病害特征及分布规律,归纳总结了基底病害成因。(2)采用静力极限分析方法,开展隧道基底软化、基底脱空、底部结构混凝土裂缝以及局部疏松条件下,隧道底部结构的承载性能分析,确定了既有缺陷损伤对底部结构承载性能的影响程度和影响规律。得出:基底软化对底部结构变形的影响更为明显,其承载性能受基底变形控制;基底脱空对底部结极限承载力影响明显,其承载性能受结构强度控制;裂缝和疏松的影响相对较小。(3)采用动力数值分析方法,系统研究基底软化、基底脱空、混凝土既有裂缝和局部疏松下底部结构列车振动响应特征,重点分析了初始损伤对隧道底部结构动位移、竖向加速度、动应力及钢筋应力响应的影响。得出:基底状况对振动响应的影响较大,且主要局限在基底以下某一深度范围内;仅存在单一初始裂缝或局部混凝土疏松损伤时,对底部结构振动响应的影响小。
[Abstract]:In recent years, with the vigorous development of China's railway construction, railway tunnels and the number of the total mileage, and the railway tunnel construction scale and speed has been ranked first in the world. The great achievements of the construction of railway tunnel service at the same time, the situation is not ideal, the operation of railway tunnel disease problems have become increasingly prominent, which occurs at the bottom of the highest rate of tunnel disease the bottom structure of railway tunnel. Service performance directly affects the safety of train operations, due to quality defects and basal conditions and other factors, the majority of the tunnel bottom structure with damage service, which seriously affect the service life of the bottom structure, at the bottom of the structure damage problems. Aiming at the tunnel bottom structure is more prominent in the practical project, using the survey and the method of combining theoretical analysis and numerical simulation, the bearing response characteristics of two performance and vibration from the bottom of the initial structure, system analysis The damage influence on service properties of tunnel bottom structure. The main contents are as follows: (1) survey of railway tunnels in China's typical bottom structure disease engineering based on case, from the bottom of bed type, disease forms, the hydrogeological conditions and causes of disease and so on, the analysis of tunnel bottom structure disease characteristics and typical defects distribution, summarized the causes of disease. The substrate (2) using the static limit analysis method, carry out the tunnel base softening, basal void, the bottom structure of concrete cracks and local osteoporosis conditions, analysis of bearing performance of tunnel bottom structure, the existing defects of damage degree and the influence rule on the performance of the bottom bearing structure is obtained. Softening effect on basal bottom structure deformation is more obvious, its bearing capacity by basement deformation control; basement void affecting the ultimate bearing capacity of the bottom. Obviously, the bearing capacity of structure strength and crack control; effect of osteoporosis is relatively small. (3) using the dynamic analysis method of numerical system of basement concrete softening, basal void, both the vibration response characteristics of bottom structure of train cracks and partial loose, analyzed the initial damage to the tunnel bottom structure displacement, vertical the acceleration effect of the dynamic stress and steel stress response. The basal condition has great effect on the response of vibration, and mainly localized in the basement below a certain depth range; there is only a single initial crack or partial loose concrete damage, the effect of bottom structure vibration response.

【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U451

【参考文献】