利用有限元分析软件建立数值计算模型,采用基线校正的10 s水平加速度时程作为地震输入条件,对在不同平台个数、平台宽度以及平台分布等多种工况下边坡模型的动力响应及稳定性进行数值模拟分析。结合各工况地震过程中坡面质点PGD放大系数、动剪应力峰值与震后最大剪应变、塑性区范围以及稳定性评价指标,对地震作用下边坡动力响应特性和失稳破坏进行了定性的评价研究。计算结果表明:以本文40 m高的边坡为例,设单个平台时,于15 m和20 m高程处设置平台对边坡动力稳定性更有利;设2个平台时,10～20 m的平台组合相对于其它组合对边坡动力稳定性更有利;对于多级边坡,随着平台宽度的增加,边坡整体破坏趋势逐渐分解为各级边坡局部破坏趋势,可以较大幅度地减小最下方坡脚的应力集中,进而提高边坡的动力稳定性;此外,平台内侧属于上级边坡的坡脚处,易产生剪应力集中区,属于薄弱部位,应加强各级坡脚的支护。
Abstract
A numerical model was established by using finite element software to simulate the dynamic response and stability of slope. In the simulation, a baseline-corrected 10s horizontal acceleration was set as earthquake input, and the platform amount, platform width and platform distribution were set different. Furthermore, according to the particle PGD amplification coefficients, peak dynamic shear stresses, maximum shear strains after earthquake, plastic zones and stability indexes of slope in different conditions during the earthquake, the dynamic response and stability of slope were quantitatively assessed. Results suggest that: for slopes of 40m high in the present paper, single platform set at 15m and 20m is beneficial to the slope’s dynamic stability; while in the case of setting double platforms, platform position at 10m-20m of the slope could better restrain the instability than other positions; for slopes of multiple levels, with the increase of platform width, the global failure trend gradually degenerates into local failure, which could greatly reduce the stress concentration at the slope toe; in addition, shear stress is prone to concentrate at the inner side of platform, so the slope toes should be strengthened at all levels.
关键词
地震 /
均质土坡 /
动力响应 /
平台 /
剪应变 /
塑性区 /
稳定性评价指标
Key words
earthquake /
homogeneous soil slope /
dynamic response /
platform /
shear strain /
plastic zone /
stability evaluation index
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参考文献
[1] 黄润秋,李为乐. “5·12”汶川大地震触发地质灾害的发育分布规律研究[J]. 岩石力学与工程学报,2008, (12):2585-2592. (HUANG Run-qiu, LI Wei-le. Research on Development and Distribution on Rules of Geohazards Induced by Wenchuan Earthquake on 12 May[J]. Chinese Journal of Rock Mechanics and Engineering,2008, (12):2585-2592. (in Chinese))
[2] 刘红帅,薄景山,刘德东. 岩土边坡地震稳定性分析研究评述[J]. 地震工程与工程振动,2005,25(1):164-171. (LIU Hong-shuai,BO Jing-shan,LIU De-dong. Review on Study of Seismic Stability Analysis of Rock-soil Slopes[J]. Earthquake Engineering and Engineering Vibration,2005,25(1):164-171. (in Chinese))
[3] 祈生文. 单面坡的两种动力反应形式及其临界高度[J]. 地球物理学报,2006,49(2):518-523. (QI Sheng-wen. Two Patterns of Dynamic Responses of Single-free-surface Slopes and Their Threshold Height[J]. Chinese Journal of Geophysics,2006,49(2):518-523. (in Chinese))
[4] 祁生文. 岩质边坡动力反应分析[M]. 北京:科学出版社,2007:40-63. (QI Sheng-wen. Rock Slope Dynamic Response Analysis[M]. Beijing:Science Press,2007:40-63. (in Chinese))
[5] 杨国香,伍法权,董金玉,等.地震作用下岩质边坡动力响应特性及变形破坏机制研究[J].岩石力学与工程学报,2012,31(4):696-702. (YANG Guo-xiang,WU Fa-quan,DONG Jin-yu,et al. Study of Dynamic Response Characters and Failure Mechanism of Rock Slope under Earthquake[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(4):696-702. (in Chinese))
[6] 卢坤林,朱大勇. 坡面形态对边坡稳定性影响的理论与试验研究[J]. 岩石力学与工程学报,2014,33(1): 35-42. (LU Kun-lin,ZHU Da-yong. Theoretical and Experimental Study of Effect of Slope Topography on Its Stability[J]. Chinese Journal of Rock Mechanics and Engineering,2014,33(1): 35-42.(in Chinese))
[7] 何 刘,吴 光,赵志明. 坡面形态对边坡动力变形破坏影响的模型试验研究[J]. 岩土力学,2014,35(1),111-117. (HE Liu,WU Guang,ZHAO Zhi-ming. Model Test of Influence of Slope Surface Morphology on Dynamic Deformation Failure[J]. Rock and Soil Mechanics,2014,35(1): 111-117. (in Chinese))
[8] 赵泽贤,王爱国. 地震动强度及坡度对边坡稳定性的影响[J]. 科学技术与工程,2012,18(6):4545-4558. (ZHAO Ze-xian,WANG Ai-guo. The Impact of Earthquake Motion Intensity and Slope Angle on the Slope Stability[J]. Science Technology and Engineering,2012,18(6):4545-4558. (in Chinese))
[9] 言志信,张 森,张学东,等. 地震边坡失稳机理及稳定性分析[J]. 工程地质学报,2010,18(6):844-850. (YAN Zhi-xin,ZHANG Sen,ZHANG Xue-dong,et al. Failure Mechanism and Stability Analysis of Slope under Earthquake[J]. Journal of Engineering Geology,2010,18(6): 844-850. (in Chinese))
[10]江德军,杨 杰,乔 蓓,等. 地震作用下土质边坡稳定性分析方法适用性分析[J]. 水电能源科学,2013,31(12): 113-116. (JIANG De-jun,YANG Jie,QIAO Bei,et al. Applicability Analysis of Soil Slope Stability Method under Action of Seismic[J]. Water Resources and Power,2013,31(12): 113-116.(in Chinese))
[11]任自铭,姚令侃. 坡面形态对地震作用下土质边坡稳定性影响[J]. 路基工程,2008,(5):5-7. (REN Zi-ming,YAO Ling-kan. Study of Effect of Slope Surface Morphology Influence on the Soil Slope Stability under the Action of Earthquake[J]. Subgrade Engineering,2008,(5):5-7. (in Chinese))
[12]言志信,郭 斌,贺 香,等. 多级边坡平台宽度对边坡地震动力响应及破坏机制的影响[J]. 岩土力学,2012,33(增2):352-358. (YAN Zhi-xin,GUO Bin,HE Xiang,et al. Study of Effect of Platform Width on Dynamic Response and Failure Mechanism of Stepped Slopes under Earthquake[J]. Rock and Soil Mechanics,2012,33(Sup.2):352-358. (in Chinese))
[13]郑颖人,赵尚毅,张鲁渝. 用有限元强度折减法进行边坡稳定分析[J]. 中国工程科学,2002,4(10):57-62. (ZHENG Ying-ren,ZHAO Shang-yi,ZHANG Lu-yu. Stability Analysis by Strength Reduction FEM[J]. Engineering Sciences, 2002,4(10):57-62. (in Chinese))
[14]刘汉龙,费 康,高玉峰. 边坡地震稳定性时程分析方法[J]. 岩土力学,2003,24(4): 553-556. (LIU Han-long,FEI Kang,GAO Yu-feng. Time History Analysis Method of Slope Seismic Stability[J]. Rock and Soil Mechanics,2003,24(4): 553-556.(in Chinese))
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