新建隧道近接既有建筑物施工的破坏模式研究

发布时间：2018-05-12 11:47

本文选题：新建隧道 + 近接既有建筑物　；参考：《现代隧道技术》2016年04期

【摘要】：地下工程近接施工影响最本质的原因是由于新建工程的施工引起围岩应力状态再次重分布,从而导致一系列的力学行为变化。文章引入强度折减法,通过数值模拟手段,对新建隧道近接既有建筑物施工的破坏模式进行了研究。研究结果表明:当新建隧道与既有建筑距离较远时,仅是隧道本身的单独失稳,不会波及建筑物;当两者距离较近时,夹岩破坏。在此基础上,根据破坏模式的差异提出两者有无近接施工影响的若干判据如下:(1)在隧道埋深不变(0°方向)的情况下,基于强度折减法的安全系数趋于定值可作为新建隧道施工对既有建筑物有无影响的判据;在隧道埋深变化(非0°方向)的情况下,安全系数达到峰值即可作为上述判据;(2)基于剪切应变增量显示的滑移带是否贯穿隧道与建筑物加载面之间的夹岩,可作为新建隧道施工对既有建筑物有无影响的形象直观判据。研究成果可为控制此类近接工程的安全风险提供理论基础,也为进一步建立影响分区、制定相关规范指南提供理论支撑。
[Abstract]:The most essential reason for the influence of near joint construction of underground engineering is that the stress state of surrounding rock is redistributed due to the construction of new construction, which leads to a series of mechanical behavior changes. In this paper, the strength reduction method is introduced, and the failure mode of the existing building near the new tunnel is studied by means of numerical simulation. The results show that when the new tunnel is far away from the existing building, it is only the single instability of the tunnel itself and will not affect the building, and when the distance between the two is close, the rock intercalation damage. On the basis of this, according to the difference of failure modes, some criteria of whether they have the influence of close connection construction are put forward as follows: 1) in the case of the tunnel buried depth not changing in the direction of 0 掳. The value of safety factor based on the strength reduction method can be used as a criterion for the influence of new tunnel construction on existing buildings, and in the case of tunnel depth change (non-0 掳direction), The peak value of safety factor can be regarded as the criterion mentioned above. (2) whether the slip band based on the increment of shear strain passes through the rock intercalation between the tunnel and the loading surface of the building can be used as the visual criterion of whether the new tunnel construction has an effect on the existing building or not. The research results can provide a theoretical basis for controlling the safety risk of this kind of close-in engineering, and also provide theoretical support for the further establishment of the impact zoning and the establishment of related norms and guidelines.
【作者单位】：西南交通大学交通隧道工程教育部重点实验室土木工程学院;
【基金】：国家自然科学基金项目(51208437,51578459) 中央高校基本科研业务费专项资金资助项目(2682015CX095)
【分类号】：U455.4

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