刚体离散元动力方法在基于位移的岩坡地震响应分析中的应用

发布时间：2018-06-27 17:25

本文选题：边坡工程 + 岩质边坡　；参考：《岩石力学与工程学报》2017年11期

【摘要】：当前岩坡地震动力响应分析中,多采用极限平衡方法分析拟静力安全系数,采用Newmark滑块分析动力永久位移,假设较多,工程实用性受限。将刚体离散元方法引入岩坡地震动力稳定性评价工作中。通过与强度折减法、Newmark法中的永久位移评价相结合,提出一种复杂岩坡静动力稳定性分析方法。初步认识表明:(1)采用极大节理刚度可以减少节理刚度带来的弹性接触位移,使得刚体离散元用于求解岩坡楔形块体的静/动力稳定性问题。(2)刚体离散元强度折减法可以无需假设块体运动方向或假定滑动形式,直接求解获取安全系数、下滑力等结果,可以考虑复杂形状块体,相比传统方法更具优势和实用性。(3)与4个经典静力算例与3个动力算例的对比验证,表明提出的刚体离散元方法及程序实现的正确性。(4)采用提出的方法,研究幅值、节理面交线倾角等参数对岩坡地震响应永久位移的影响规律研究,表明刚体离散元方法可以根据参数变化得到正确的得到相应的结果变化规律。且对比发现在某些特定条件下拟静力安全系数不能正确反映岩坡地震响应的陡增程度。(5)在工程实例中,采用刚体离散元方法进行K1块体基于位移的地震稳定性评价,给出基于超越概率的支护设计方案。相比拟静力安全系数设计方案,在满足使用条件的前提下优化程度更高。研究可为岩坡静动力稳定性分析提供一种新的思路。
[Abstract]:In the current seismic dynamic response analysis of rock slope, the limit equilibrium method is used to analyze the pseudo static safety factor, and the Newmark slider is used to analyze the dynamic permanent displacement. The assumption is more and the engineering practicability is limited. The rigid body discrete element method is introduced into the evaluation of the dynamic stability of the rock slope. The permanent position in the Newmark method and the strength reduction method are adopted. A method of static and dynamic stability analysis of complex rock slope is proposed by the combination of translation evaluation. The preliminary understanding shows that (1) the elastic contact displacement can be reduced by the maximum joint stiffness, and the rigid body discrete element can be used to solve the static / dynamic stability problem of the wedge block of rock slope. (2) the strength reduction method of rigid body discrete element can not be needed. Assuming the direction of the motion of the block or assuming the sliding form to obtain the results of obtaining the safety factor and the sliding force directly, the complex shape block can be considered. Compared with the traditional method, the block body can be more advantageous and practical. (3) the correctness of the proposed rigid body discrete element method and the implementation of the program is proved by comparison with the 4 classical static calculation examples and 3 dynamic examples. (4 Using the proposed method, the influence of the parameters of the amplitude and the intersection angle of the joint surface on the permanent displacement of the rock slope seismic response is studied. It is shown that the rigid body discrete element method can get the correct change rule of the corresponding results according to the change of the parameters. And the comparison shows that the static safety coefficient of the static force can not be correctly reflected under certain conditions. The steep increase in seismic response of rock slope. (5) in the engineering example, the rigid body discrete element method is used to evaluate the seismic stability of K1 block based on displacement, and the support design scheme based on the transcendental probability is given. Compared with the quasi static safety factor design scheme, the optimization degree is higher under the condition of satisfying the conditions. The stability analysis provides a new way of thinking.
【作者单位】：中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室;
【基金】：NSFC 云南联合基金重点支持项目(U1402231) 国家重点基础研究发展计划(973)项目(2015CB057905) 国家自然科学基金资助项目(51779253)~~
【分类号】：P315.9

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