空洞对盾构隧道结构受力与破坏影响模型试验研究

发布时间：2018-04-09 18:56

本文选题：盾构隧道　切入点：模型试验　出处：《岩土工程学报》2017年01期

【摘要】：通过将渐进性破坏理论应用到盾构隧道管片衬砌结构病害(尤其是管片开裂)产生的破坏分析中,采用相似模型试验方法,通过超载的形式从管片衬砌结构内力及位移、声发射信息、管片破坏过程方面,分析地层空洞缺陷对盾构隧道管片从材料细观损伤到结构宏观局部破坏再到结构整体失稳的整个渐进性破坏失稳过程的影响。试验结果表明:空洞缺陷的存在对衬砌结构的极限承载能力及破坏模式具有显著影响,首先是会降低管片失稳临界点对应荷载值,临界点对应的最大位移值与隧道半径比值减小,其次降低管片结构开始出现宏观裂缝时的荷载值;对于空洞的分布位置,拱肩位置空洞的存在更容易导致结构的失稳,其次拱腰和拱顶;空洞的存在也会改变衬砌结构失稳起始位置的分布,导致失稳起始位置接近或直接位于空洞位置。
[Abstract]:By applying the progressive failure theory to the damage analysis of shield tunnel segment lining structure (especially segment cracking), the similar model test method is used to analyze the internal force and displacement of the segment lining structure through the form of overload.In the aspect of acoustic emission information and segment failure process, the influence of formation cavity defects on the whole progressive failure process of shield tunnel segment from material meso damage to macroscopic local failure of structure to overall instability of structure is analyzed.The test results show that the existence of cavity defects has a significant impact on the ultimate bearing capacity and failure mode of lining structure. First of all, the corresponding load value of critical point of segment instability will be reduced.The ratio of maximum displacement to tunnel radius of critical point decreases, then decreases the load value of segment structure when macroscopic cracks begin to appear, and for the distribution of cavity, the existence of hole in arch shoulder position is more likely to lead to instability of the structure.Secondly, the existence of cavities will change the distribution of the initial location of the instability of the lining structure, resulting in the initial location of the instability close to or directly located in the cavity position.
【作者单位】：西南交通大学交通隧道工程教育部重点实验室;
【基金】：国家自然科学基金面上项目(51278424);国家自然科学基金青年基金项目(50908194) 中央高校基本科研业务费专项资金项目(2682014CX070)
【分类号】：U451;U455.43

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