跃龙门隧道洞口段二次衬砌抗震分析

发布时间：2018-06-11 22:04

本文选题：洞口段 + 二次衬砌　；参考：《辽宁工程技术大学》2015年硕士论文

【摘要】：近年来,世界各国地震频发,给人民的生命和财产带来严重威胁,隧道结构是地下交通系统的重要结构,隧道结构的破坏,不仅导致巨大的直接经济损失,而且还会阻碍救援工作的展开,导致重建工作拖延。对于整座隧道而言,在地震中隧道洞口最容易受到破坏,因此对隧道洞口段二次衬砌进行抗震研究显得十分必要。通过查阅相应规范,确定浅埋隧道洞口段必须加强衬砌设计(即抗震设防),但并未能对如何进行抗震设防设计做出规定,设计中常常根据经验对衬砌进行加强,衬砌能否在设防烈度地震荷载作用下保持结构完好具有很大的不确定性,衬砌刚度提高是否能提高其抗震性能也有待研究。针对以上问题,本文以跃龙门隧道洞口段二次衬砌为研究对象,以数值模拟为手段,对三维地震动作用下隧道洞口段二次衬砌进行动力响应分析,分析三维地震动作用的洞口段二次衬砌的最大位移、加速度、应力和内力,并进行抗压、抗拉强度验算。最后对不同刚度洞口段二次衬砌的抗震性能进行探讨,得出以下主要结论：(1)三维地震动作用下,隧道洞口段二次衬砌的应力、剪力及弯矩最大值均在拱脚处取得,拱脚处应力集中。设计时应对拱脚处采取措施以减小拱脚处受力。(2)三维地震动作用下,跃龙门隧道洞口段二次衬砌的抗拉、抗压性能均满足规范要求,且抗拉及抗压安全系数均大于规范要求值。跃龙门隧道洞口段二次衬砌抗震设防合理。(3)提高混凝土强度不能明显提高洞口段二次衬砌的抗震性能。
[Abstract]:In recent years, earthquakes have occurred frequently all over the world, which have brought serious threat to people's lives and property. Tunnel structure is an important structure of underground traffic system. The destruction of tunnel structure not only leads to huge direct economic losses. It also impedes relief efforts and delays reconstruction efforts. For the whole tunnel, the tunnel opening is the most vulnerable to damage in the earthquake, so it is very necessary to study the earthquake resistance of the secondary lining of the tunnel opening. By referring to the corresponding codes, it is determined that the lining design must be strengthened (i.e. seismic fortification) at the entrance of shallow buried tunnel, but it fails to stipulate how to carry out seismic fortification design, and the lining is often strengthened according to the experience in the design. It is uncertain whether the lining can keep the structure intact under the earthquake load of fortification intensity, and whether the improvement of the lining stiffness can improve the seismic performance of the lining remains to be studied. Aiming at the above problems, this paper takes the secondary lining of Yuelongmen tunnel as the research object, and takes the numerical simulation as the means to analyze the dynamic response of the secondary lining of the tunnel under the action of three-dimensional ground motion. This paper analyzes the maximum displacement, acceleration, stress and internal force of the secondary lining in the opening section of the three-dimensional ground motion, and checks the compressive and tensile strength of the lining. Finally, the aseismic behavior of the secondary lining of the tunnel with different stiffness is discussed. The main conclusions are as follows: 1) under the action of 3-D ground motion, the maximum stress, shear force and bending moment of the secondary lining of the tunnel entrance are obtained at the arch foot. Stress concentration at arch foot. Under the action of 3-D ground motion, the tensile and compressive properties of the secondary lining at the entrance of Yuelongmen Tunnel all meet the requirements of the specification, and the safety factors of tensile and compression are higher than the required values of the specifications. The aseismic behavior of the secondary lining in the opening section of Yuelongmen Tunnel is not obviously improved by increasing the concrete strength.
【学位授予单位】：辽宁工程技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452.28

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