强震作用下偏压隧道结构动力响应研究

发布时间：2018-03-16 11:49

  本文选题：隧道　切入点：偏压　出处：《西南交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：隧道穿越山体时,在浅埋地段受地形的影响,衬砌结构很容易处于偏压的受力状态,当偏压隧道处于高寒地区时,由于冬季温度较低,夏季温度相对较高,偏压隧道将承受冻融循环带来的不利影响。因此,研究偏压隧道的地震动力响应规律以及温度因素对偏压隧道地震动力响应的影响具有重大的工程意义。本文通过数值模拟的方法分析了偏压隧道的地震动力响应特性,并在此基础上探究了温度场对其动力响应的影响。本文的主要研究工作及成果如下：(1)通过收集整理山岭隧道震害资料,明确了研究地形因素及温度因素对偏压隧道动力响应影响的重要性。(2)分析了单一围岩条件下偏压山岭隧道洞口结构的动力响应,得出结论：偏压地形会增大洞口段长度。在Ⅳ级围岩、边坡倾角30°条件下,洞口段长度相比非偏压条件下洞口段长度放大了1.5倍。(3)通过取距洞口30m处横断面进行分析,研究了不同边坡倾角下隧道结构的地震动力响应。偏压隧道在地震作用下的弯矩峰值、剪力峰值在靠山侧拱脚处最大,轴力峰值在背山侧拱肩处最大。满足一定的工程精度时,Ⅳ级围岩、拱顶埋深15m条件下,偏压隧道与非偏压隧道在地震作用下的临界边坡倾角可取为20°。(4)研究了不同边坡覆土厚度对偏压隧道动力响应的影响。随着边坡覆土厚度的增加,隧道各部位动力响应的不对称性逐渐减弱。动力条件下临界覆土厚度约为静力条件下根据塌落拱理论计算的临界覆土厚度的1.8～1.96倍。(5)研究了冻融循环对偏压隧道动力响应的影响。研究表明,冻融循环对偏压隧道在地震期间位移和内力响应时程规律无明显影响,只是改变了位移和内力的响应峰值。考虑冻融循环时,偏压隧道位移响应峰值和内力响应峰值相比不考虑冻融循环时均有所增加。
[Abstract]:When the tunnel passes through the mountain body, the lining structure is easy to be in the state of bias pressure when the tunnel passes through the mountain body. When the tunnel is in the high and cold area, the temperature is relatively high in summer because of the lower temperature in winter. The bias tunnel will suffer the adverse effects of freeze-thaw cycles. It is of great engineering significance to study the seismic dynamic response of the bias tunnel and the influence of temperature factors on the seismic dynamic response of the bias tunnel. In this paper, the seismic dynamic response characteristics of the bias tunnel are analyzed by numerical simulation. On this basis, the influence of temperature field on its dynamic response is explored. The main work and results of this paper are as follows: 1) through collecting and sorting out the seismic damage data of mountain tunnels, The importance of studying the influence of topographic factors and temperature factors on the dynamic response of the eccentric tunnel is defined. (2) the dynamic response of the tunnel entrance structure under the condition of single surrounding rock is analyzed. Under the condition of grade 鈪，

本文编号：1619787