In engineering practice simplified methods are essential to the seismic design of embedded earth retaining walls,as fullydynamic numerical analyses are costly,time-consuming and require specific expertise.Recently dev...In engineering practice simplified methods are essential to the seismic design of embedded earth retaining walls,as fullydynamic numerical analyses are costly,time-consuming and require specific expertise.Recently developed pseudostatic methods provide earth stresses and internal forces,even in those cases in which the strength of the soil surrounding the structure is not entirely mobilised.Semiempirical correlations or Newmark sliding block method provide an estimate of earthquake-induced permanent displacements.However,the use of these methods is hindered by uncertainties in the evaluation of a few input parameters,affecting the reliability of the methods.This study uses 1 D site response analyses and 2 D fully-dynamic finite element analyses to show that simplified methods can provide a reasonable estimate of the maximum bending moment and permanent displacements for stiff cantilever walls embedded in uniform sand,providing that a few input parameters are evaluated through semiempirical correlations and a simple 1 D site response analysis.展开更多
在我国重要高坝工程抗震设计中,采用设定地震方法确定坝址场地相关设计反应谱时,同时依据地震安评和NGA反应谱衰减关系,但两者的震源和参数不匹配。本文在当前研究现状下提出确定场地相关设计反应谱的方法:基于全球范围的NGA WEST 2数据...在我国重要高坝工程抗震设计中,采用设定地震方法确定坝址场地相关设计反应谱时,同时依据地震安评和NGA反应谱衰减关系,但两者的震源和参数不匹配。本文在当前研究现状下提出确定场地相关设计反应谱的方法:基于全球范围的NGA WEST 2数据库,构建以震级和震中距分档的反应谱数据库。针对混凝土坝和坐落在深厚覆盖层的土石坝,分别建立来自基岩近场和远场大震强震动记录的反应谱数据库。根据设定地震的震级和距离,从反应谱数据库分步插值,直接给出与设计峰值加速度相应的场地相关设计反应谱。采用上述思路确定场地相关设计反应谱,避开了具有诸多不确定性且与地震安评不匹配的反应谱衰减关系,其结果更为合理。展开更多
文摘In engineering practice simplified methods are essential to the seismic design of embedded earth retaining walls,as fullydynamic numerical analyses are costly,time-consuming and require specific expertise.Recently developed pseudostatic methods provide earth stresses and internal forces,even in those cases in which the strength of the soil surrounding the structure is not entirely mobilised.Semiempirical correlations or Newmark sliding block method provide an estimate of earthquake-induced permanent displacements.However,the use of these methods is hindered by uncertainties in the evaluation of a few input parameters,affecting the reliability of the methods.This study uses 1 D site response analyses and 2 D fully-dynamic finite element analyses to show that simplified methods can provide a reasonable estimate of the maximum bending moment and permanent displacements for stiff cantilever walls embedded in uniform sand,providing that a few input parameters are evaluated through semiempirical correlations and a simple 1 D site response analysis.
文摘在我国重要高坝工程抗震设计中,采用设定地震方法确定坝址场地相关设计反应谱时,同时依据地震安评和NGA反应谱衰减关系,但两者的震源和参数不匹配。本文在当前研究现状下提出确定场地相关设计反应谱的方法:基于全球范围的NGA WEST 2数据库,构建以震级和震中距分档的反应谱数据库。针对混凝土坝和坐落在深厚覆盖层的土石坝,分别建立来自基岩近场和远场大震强震动记录的反应谱数据库。根据设定地震的震级和距离,从反应谱数据库分步插值,直接给出与设计峰值加速度相应的场地相关设计反应谱。采用上述思路确定场地相关设计反应谱,避开了具有诸多不确定性且与地震安评不匹配的反应谱衰减关系,其结果更为合理。
