基于强度折减的边坡动力安全系数确定方法研究
|
摘要
地震边坡稳定性分析已成为岩土工程界和地震工程界抗震减灾研究的重要课题之一。通过数值分析对土质边坡地震动力响应规律进行研究,发现边坡上PGA分布突变点的连线与潜在滑动面位置存在较好的对应关系。据此可通过PGA分布突变点的连线轮廓来大致确定边坡的潜在滑裂面,同时,这些PGA分布突变点可以选定为判定坡体临界稳定状态的关键点。基于强度折减法,以关键点的相对位移作为边坡动力破坏的控制性指标,结合地震特征位移和安全系数来评价边坡的动力稳定性,以特征位移与强度折减系数曲线上的特征位移产生突变时对应的强度折减系数作为边坡的地震动力安全系数。
The seismic stability of the slop has become an important research topic in geotechnical and seismic engineering.A numerical model has been set up to analyze the seismic response law of the soil slop.It is revealed that the ligature of PGA catastrophe points has good agreements with the potential sliding surface,thus the potential sliding surface can be determined by the ligature.Also,these PGA catastrophe points can be used as strategic points to distinguish the critical stable state of the soil slop.Based on strength reduction method,the relative displacement of the strategic points can be used as controlling indices of the slop dynamic damage;the dynamic stability of the slop can be assessed along with the seismic features displacement and safety coefficient;the corresponding strength reduction coefficient where features displacement mutations on the features displacement and strength reduction coefficient curve can be used as seismic dynamic safety factor of slop.
The seismic stability of the slop has become an important research topic in geotechnical and seismic engineering.A numerical model has been set up to analyze the seismic response law of the soil slop.It is revealed that the ligature of PGA catastrophe points has good agreements with the potential sliding surface,thus the potential sliding surface can be determined by the ligature.Also,these PGA catastrophe points can be used as strategic points to distinguish the critical stable state of the soil slop.Based on strength reduction method,the relative displacement of the strategic points can be used as controlling indices of the slop dynamic damage;the dynamic stability of the slop can be assessed along with the seismic features displacement and safety coefficient;the corresponding strength reduction coefficient where features displacement mutations on the features displacement and strength reduction coefficient curve can be used as seismic dynamic safety factor of slop.
引文
[1]薄景山,徐国栋,景立平.土边坡地震反应及其动力稳定性分析述[J].地震工程与工程振动,2001,21(2):116-110
[2]Larryr T,Max P T,Dellinger A S,et al.Seismic stabilityanalysis for geosynthetic clay liner landfill cover placementon steep slope[M].ASCE,1995:196-211
[3]刘汉龙,费康,高玉峰.边坡地震稳定性时程分析法[J].岩土力学,2003,24(4):553-556
[4]戴妙林,李同春.基于降强法数值计算的复杂岩质边坡动力稳定性安全评价分析[J].岩石力学与工程学报,2007,26(1):2749-2754
[5]郑颖人,叶海林,黄润秋.地震边坡破坏机制及其破裂面的分析探讨[J].岩石力学与工程学报,2009,28(8):1714-1723
[6]张鲁渝,郑颖人,赵尚毅,时卫民.有限元强度折减系数法计算土坡稳定安全系数的精度研究[J].水利学报,2003(1):21-27
[7]赵尚毅,郑颖人,张玉芳.极限分析有限元法讲座——II有限元强度折减法中边坡失稳的判据探讨[J].岩土力学,2005,26(2):332-336
[8]任自铭,冯仲林,殷世林.土质边坡剖面上动力响应异常点与潜在滑动面位置的关系研究[J].西北地震学报,2009,31(1):21-25
[2]Larryr T,Max P T,Dellinger A S,et al.Seismic stabilityanalysis for geosynthetic clay liner landfill cover placementon steep slope[M].ASCE,1995:196-211
[3]刘汉龙,费康,高玉峰.边坡地震稳定性时程分析法[J].岩土力学,2003,24(4):553-556
[4]戴妙林,李同春.基于降强法数值计算的复杂岩质边坡动力稳定性安全评价分析[J].岩石力学与工程学报,2007,26(1):2749-2754
[5]郑颖人,叶海林,黄润秋.地震边坡破坏机制及其破裂面的分析探讨[J].岩石力学与工程学报,2009,28(8):1714-1723
[6]张鲁渝,郑颖人,赵尚毅,时卫民.有限元强度折减系数法计算土坡稳定安全系数的精度研究[J].水利学报,2003(1):21-27
[7]赵尚毅,郑颖人,张玉芳.极限分析有限元法讲座——II有限元强度折减法中边坡失稳的判据探讨[J].岩土力学,2005,26(2):332-336
[8]任自铭,冯仲林,殷世林.土质边坡剖面上动力响应异常点与潜在滑动面位置的关系研究[J].西北地震学报,2009,31(1):21-25
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心