隧道爆破振动下砌体结构局部动力反应研究

发布时间：2018-01-27 15:28

本文关键词： 隧道爆破高频振动砌体结构动力反应高阶局部模态应力损伤　出处：《现代隧道技术》2017年03期 　论文类型：期刊论文

【摘要】：文章依托成渝客专新红岩隧道爆破工程,选取典型实测爆破地震波和典型二层砌体结构,分析了砌体结构的低阶整体模态和高阶局部模态,采用振型位移叠加法理论分析了隧道爆破振动下结构的位移和应力反应特征,研究了不同峰值振速下砌体砖墙的主拉应力分布及变化规律。结果表明:典型二层砌体结构1~5阶为低阶整体模态,固有频率为8.80~24.86 Hz,振型为整体均匀变形;6~20阶为高阶局部密集模态,固有频率为25.96~36.14 Hz,局部变形显著大于整体变形;高频的隧道爆破振动引起的结构位移很小,而局部构件上的内力要比位移大得多,这是因为结构内力计算中的振型幅值向量乘以了振型频率的平方;隧道爆破振动下结构的动力损伤主要由瞬时产生的高应力控制,而不是位移;砖墙的门、窗洞角处及砖墙与混凝土构件接触的应力集中部位和女儿墙、侧墙、中隔墙、阳台等局部构件振动较大的部位受拉应力较大,在隧道爆破振动下容易产生损伤。
[Abstract]:In this paper, based on the blasting engineering of Chengdu-Kejiuxinhongyan tunnel, typical measured blasting seismic waves and typical two-story masonry structures are selected, and the low-order integral modes and high-order local modes of masonry structures are analyzed. The displacement and stress response characteristics of the structure under blasting vibration are analyzed by using the mode displacement superposition method. The main tensile stress distribution and variation law of masonry masonry wall under different peak vibration velocities are studied. The results show that 1 / 5 order of typical two-story masonry structure is a low order integral mode. The natural frequency is 8.80 Hz and the mode shape is uniform deformation. Order 6 ~ 20 is a high order local dense mode with a natural frequency of 25.96 ~ 36.14 Hz. The local deformation is significantly larger than that of the whole deformation. The structural displacement caused by high frequency blasting vibration of tunnel is very small, and the internal force on the local members is much larger than the displacement, which is because the amplitude vector of the vibration mode is multiplied by the square of the mode frequency in the calculation of the internal force of the structure. The dynamic damage of the structure under blasting vibration is mainly controlled by the instantaneous high stress rather than the displacement. The door, window and hole corner of brick wall and the stress concentration part of contact between brick wall and concrete member and parapet wall, side wall, middle partition wall, balcony and other parts of local members are subjected to higher tensile stress. It is easy to produce damage under blasting vibration of tunnel.
【作者单位】：青岛理工大学土木工程学院;河北建设勘察研究院有限公司;河北省岩土工程研究中心;北京交通大学土木建筑工程学院;清华大学土木水利学院;北京市市政二建设工程有限责任公司;
【基金】：国家自然科学基金资助项目(51278042) 山东省自然科学基金资助项目(ZR2016EEB27)
【分类号】：U455.6
【正文快照】： 修改稿返回日期:2016-08-111引言近年来,国家加快了高速铁路和地下铁路等基础设施建设,使得近距离下穿市区密集建筑群的隧道工程越来越多。当采用钻爆法进行隧道开挖时,在隧道爆破近区产生的地面振动频率高、幅值大,很可能会对周围环境及建筑物产生不利影响,尤其是对于抗震强

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