地震动输入方向对空间框架非线性反应特征的影响
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摘要
在钢筋混凝土结构的非线性反应分析中,地震动通常简化为沿结构的主轴方向输入,地震波的最不利输入方向问题经常被忽略。以三个规则、对称的钢筋混凝土典型空间框架为例,在OpenSees平台上,采用基于柔度法的纤维模型从而更加真实地模拟柱在双向弯曲和变化轴力作用下的非线性反应,通过多角度输入地震波对各框架进行了罕遇烈度水准下的非线性反应分析。结果表明,规则、对称空间框架的柱端出铰率、混凝土纤维压应变以及钢筋纤维拉应变的地震动最不利输入方向是45°、135°,梁端出铰率、纤维应变、转角延性的最不利方向为主轴方向,柱端转角延性的地震动最不利输入方向不明显,仅沿结构主轴方向输入地震波无法得到最不利的塑性耗能特征。
In the nonlinear responses analysis of reinforced concrete structures,seismic wave input angles are usually simplified as paralleling to the principal axis of structures,and the problem of critical excitation angle is generally ignored.In this paper,three regular and symmetrical reinforced concrete typical spatial frames were employed as examples.Based on the OpenSees framework,flexibility method based fiber model was adopted to simulate the nonlinear responses of the columns under biaxial bending and varying axial forces.Nonlinear dynamic response analyses of the three frames under rare earthquake excitations with varying seismic wave input angles were carried out.The results show that for the regular and symmetrical spatial frames,the critical excitation angle of compressive strain of concrete fibers,tensile strain of steel fibers and ratio of plastic hinges at column ends are 45° and 135°,the critical excitation angle of strain of concrete fiber and steel fiber,ratio of plastic hinges and rotation ductility at beam ends are principal axis of structures.The critical excitation angle of rotation ductility at column ends is not apparent.It cannot get critical energy dissipation characteristics of plastic hinges if seismic wave was input along the principal axis direction.
In the nonlinear responses analysis of reinforced concrete structures,seismic wave input angles are usually simplified as paralleling to the principal axis of structures,and the problem of critical excitation angle is generally ignored.In this paper,three regular and symmetrical reinforced concrete typical spatial frames were employed as examples.Based on the OpenSees framework,flexibility method based fiber model was adopted to simulate the nonlinear responses of the columns under biaxial bending and varying axial forces.Nonlinear dynamic response analyses of the three frames under rare earthquake excitations with varying seismic wave input angles were carried out.The results show that for the regular and symmetrical spatial frames,the critical excitation angle of compressive strain of concrete fibers,tensile strain of steel fibers and ratio of plastic hinges at column ends are 45° and 135°,the critical excitation angle of strain of concrete fiber and steel fiber,ratio of plastic hinges and rotation ductility at beam ends are principal axis of structures.The critical excitation angle of rotation ductility at column ends is not apparent.It cannot get critical energy dissipation characteristics of plastic hinges if seismic wave was input along the principal axis direction.
引文
[1]范立础,聂利英,李建中.复杂结构地震波输入最不利方向标准问题[J].同济大学学报,2003,31(6):631-636.
[2]冯云田,李明瑞,林春哲.复杂结构的弹性地震反应分析[J].地震工程与工程振动,1991,11(4):77-86.
[3]聂利英,李建中,范立础.复杂结构地震输入方向的基本原理及其影响[J].地震工程与工程振动,2003,23(3):30-34.
[4]高晓安,周锡元.曲线桥梁在多向地震作用下的动力分析方法[J].特种结构,2005,22(1):56-59.
[5]何晓宇,李宏男.海洋平台确定多维地震动最不利输入方向的一种有效方法[J].振动与冲击,2007,26(12):49-54.
[6]全伟,李宏男.曲线桥多维地震时程分析主方向研究[J].振动与冲击,2008,27(8):20-24.
[7]宋波,潘建仕.基于Pushover法的曲线桥地震波输入最不利角度分析[J].北京科技大学学报,2008,30(11):1223-1229.
[8]秦力,裴宁波,黄依宁.平面不规则结构的弹塑性时程分析[J].东北电力大学学报:自然科学版,2009,29(1):62-66.
[9]MacRae G A,Mattheis J.Three-Dimensional Steel BuildingResponse to Near-fault Motions[J].Journal of StructuralEngineering,2000,126(1):117-126.
[10]杨红,朱振华,白绍良.双向地震作用下我国“强柱弱梁”措施的有效性评估[J].土木工程学报,2011,44(1):58-64.
[11]杨红,王建辉,白绍良.双向地震作用对柱端弯矩增大系数的影响分析[J].土木工程学报,2008,41(9):40-47.
[12]Mazzoni S,McKenna F,Scott M H,et al.Open System forEarthquake Engineering Simulation Users Command-LanguageManual[M/OL].Berkeley:University of California,2012.http://opensees.berkeley.edu/wiki/index.php/Command_Manual.
[13]杨红,高文生,王志军.空间框架简化为平面模型的抗震分析[J].重庆大学学报,2008,31(11):1267-1272.
[2]冯云田,李明瑞,林春哲.复杂结构的弹性地震反应分析[J].地震工程与工程振动,1991,11(4):77-86.
[3]聂利英,李建中,范立础.复杂结构地震输入方向的基本原理及其影响[J].地震工程与工程振动,2003,23(3):30-34.
[4]高晓安,周锡元.曲线桥梁在多向地震作用下的动力分析方法[J].特种结构,2005,22(1):56-59.
[5]何晓宇,李宏男.海洋平台确定多维地震动最不利输入方向的一种有效方法[J].振动与冲击,2007,26(12):49-54.
[6]全伟,李宏男.曲线桥多维地震时程分析主方向研究[J].振动与冲击,2008,27(8):20-24.
[7]宋波,潘建仕.基于Pushover法的曲线桥地震波输入最不利角度分析[J].北京科技大学学报,2008,30(11):1223-1229.
[8]秦力,裴宁波,黄依宁.平面不规则结构的弹塑性时程分析[J].东北电力大学学报:自然科学版,2009,29(1):62-66.
[9]MacRae G A,Mattheis J.Three-Dimensional Steel BuildingResponse to Near-fault Motions[J].Journal of StructuralEngineering,2000,126(1):117-126.
[10]杨红,朱振华,白绍良.双向地震作用下我国“强柱弱梁”措施的有效性评估[J].土木工程学报,2011,44(1):58-64.
[11]杨红,王建辉,白绍良.双向地震作用对柱端弯矩增大系数的影响分析[J].土木工程学报,2008,41(9):40-47.
[12]Mazzoni S,McKenna F,Scott M H,et al.Open System forEarthquake Engineering Simulation Users Command-LanguageManual[M/OL].Berkeley:University of California,2012.http://opensees.berkeley.edu/wiki/index.php/Command_Manual.
[13]杨红,高文生,王志军.空间框架简化为平面模型的抗震分析[J].重庆大学学报,2008,31(11):1267-1272.
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