含小净距隧道岩石边坡地震动力响应特性研究

发布时间：2018-03-25 13:02

本文选题：地震工程　切入点：岩质边坡　出处：《自然灾害学报》2017年05期

【摘要】：采用有限元分析软件建立一个通过大型振动台模型试验验证的边坡动力数值分析模型,研究了地震作用下含小净距隧道岩石边坡的动力响应规律,探讨了隧道结构对边坡动力响应规律的影响。结果表明:1)边坡加速度峰值放大系数沿坡面向上呈现出先减小后增大的非线性变化特征,存在临空面放大作用,边坡会改变输入地震波的频谱成分,对高频段地震波存在滤波作用,对低频段地震波存在放大作用;2)因小净距隧道的存在,含小净距隧道边坡的坡面加速度分布较无隧道边坡表现出明显的非线性高程特性,其坡体最大水平和竖向位移总体上小于无隧道边坡;3)强震作用下坡顶和结构面附近水平位移最大,两隧道中夹岩处及偏压侧隧道左侧拱脚处易发生拉裂破坏和剪切破坏。试验研究结果对含小净距隧道边坡抗震设计及其地震动力反应特性的研究有一定的指导意义。
[Abstract]:The finite element analysis software is used to establish a numerical model of slope dynamic analysis, which is verified by large shaking table model test, and the dynamic response of rock slope with small spacing tunnel under earthquake action is studied. The influence of tunnel structure on slope dynamic response is discussed. The results show that the peak magnification factor of slope acceleration shows a nonlinear variation characteristic of decreasing first and then increasing along the slope surface. The slope will change the frequency spectrum of the input seismic wave, filter the seismic wave in the high frequency band and amplify the seismic wave in the low frequency band. The slope acceleration distribution of tunnel slope with small net distance shows obvious nonlinear elevation characteristics compared with no tunnel slope. The maximum horizontal and vertical displacement of the slope is generally smaller than the maximum horizontal displacement near the slope top and the structural plane under the action of strong earthquake without tunnel slope. Tensile cracking and shear failure are easy to occur at the rock intercalation in the two tunnels and at the left arch of the bias side tunnel. The experimental results are of certain guiding significance to the seismic design and seismic dynamic response characteristics of the tunnel slope with small spacing.
【作者单位】：中南林业科技大学土木工程与力学学院;
【基金】：国家自然科学基金(51204215,51404309)~~
【分类号】：U452.28

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