断层错动对岩石隧道影响的振动台试验研究

发布时间：2018-06-27 22:34

本文选题：隧道 + 断层　；参考：《南京工业大学》2015年硕士论文

【摘要】：伴随大规模基础设施建设的开展,隧道等地下工程需要穿越断层的情况已成为一种常态。由此断层所引发的工程问题也日渐普遍,其研究也越来越引起人们的关注。针对强震作用下隧道工程不断受到断层错动严重破坏的实际,论文开展了地震作用下活化断层之隧道工程效应的振动台试验研究。取得了富有创新性的研究结果：(1)验证了在几何相似比为100的情况下,铁晶砂胶结材料用于模拟围岩性态的可行性。该材料容重高,易于模型与原型之间相似比的换算；其弹性模量和抗压/拉强度较低,同时能较好地模拟出实际岩体的脆性特征。(2)断层倾角和断层上下盘对围岩的工程性态有着重要的影响。试验模拟隧道穿越300、450和600倾角的断层,发现当断层倾角为450时围岩对输入波的动力反应最大,断层倾角为300时围岩对输入波的动力反应次之,断层倾角为600时围岩对输入波的动力反应最小。通过对围岩上下盘加速度数据和隧道表面应变数据分析,发现同一深度处上盘围岩加速度峰值为下盘围岩加速度峰值的2.2～2.5倍；断层上盘隧道受围岩压力比下盘大。说明下盘围岩相对于上盘围岩受地震震动影响较小。(3)围岩对不同加载地震波有着不同的响应。通过分析在Kobe波和El-Centro波作用下围岩的加速度反应峰值,发现随着两种地震波地震幅值的不断增大,围岩各点的加速度峰值不断增大；在地面以下同一位置处,在El-Centro波作用下的围岩加速度峰值为在Kobe波作用下的2.5～3.5倍。说明El-Centro波对围岩的扰动比Kobe波大。(4)通过分析断层上盘隧道应变随地震波幅值的增大而变化的趋势,发现随着地震波幅值的增大,隧道上下表面应变不断增大,通过分析不同刚度隧道上下表面的应变数据,发现刚度较大的隧道所受应变较小且随着离断层水平距离越大,断层上盘一侧隧道表面应变呈现出先增后降的趋势。
[Abstract]:With the development of large-scale infrastructure construction, it has become a normal condition that tunnels and other underground projects need to cross faults. The engineering problems caused by this fault are becoming more and more common, and its research has attracted more and more attention. In view of the fact that tunnel engineering has been seriously damaged by fault dislocation under strong earthquake, the shaking table test study of tunnel engineering effect of activated fault under earthquake action has been carried out in this paper. The results are as follows: (1) the feasibility of using the ferro-grained sand cementing material to simulate the surrounding rock behavior is verified under the condition of geometric similarity ratio of 100. The material has high bulk density and is easy to convert the similarity ratio between the model and the prototype, and its elastic modulus and compressive / tensile strength are low. At the same time, the brittleness characteristics of real rock mass can be well simulated. (2) the slope of fault and the upper and lower face of fault have important influence on the engineering behavior of surrounding rock. The test results show that the dynamic response of the surrounding rock to the input wave is the largest when the dip angle of the fault is 300450 and 300450, and the second is the dynamic response of the surrounding rock to the input wave when the dip angle of the fault is 300450. When the fault dip angle is 600, the dynamic response of surrounding rock to the input wave is minimum. Through the analysis of the acceleration data of the upper and lower wall rock and the strain data of the tunnel surface, it is found that the peak value of the acceleration of the upper wall rock at the same depth is 2.2or 2.5 times the peak value of the acceleration peak of the lower wall rock. It shows that the lower wall rock is less affected by earthquake vibration than the upper wall rock. (3) the surrounding rock has different response to different loading seismic waves. By analyzing the acceleration peak of surrounding rock under the action of Kobe wave and El-Centro wave, it is found that the acceleration peak of surrounding rock increases with the increasing of seismic amplitude of the two kinds of seismic waves, and the acceleration peak of surrounding rock at the same position below the ground. The peak acceleration of surrounding rock under the action of El-Centro wave is 3.5 times higher than that under Kobe wave. It shows that the disturbance of El-Centro wave to surrounding rock is greater than that of Kobe wave. (4) by analyzing the tendency of tunnel strain changing with the increase of seismic wave amplitude, it is found that with the increase of seismic wave amplitude, the upper and lower surface strain of tunnel increases continuously. By analyzing the strain data of the upper and lower surface of the tunnel with different stiffness, it is found that the strain of the tunnel with larger stiffness is smaller and the surface strain of the tunnel on the upper side of the fault increases first and then decreases with the increase of the horizontal distance from the fault.
【学位授予单位】：南京工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U456

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