基于JC法的近场地震作用下钢筋混凝土高墩塑性铰形成概率分析
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摘要
为研究近场地震动作用下钢筋混凝土(RC)高墩塑性铰形成概率。以高度为90 m的某RC高墩为研究对象,首先采用支持向量机算法预测截面等效屈服曲率;然后考虑墩身参数和近场地震动的随机性,采用OpenSees建立高墩模型,并进行增量动力非线性分析;最后以等效屈服曲率为临界指标,采用JC法对截面动力响应当量正态化后,计算分析截面塑性铰形成概率。研究结果表明:RC高墩截面顺桥向和横桥向等效屈服曲率均具有明显的离散性且服从正态分布;顺桥向近场地震作用下,墩底和墩身中部区域塑性铰形成概率均较大并形成塑性铰,且墩身中部塑性铰长度达31.7 m,比只考虑地震动随机性确定的塑性铰区域长度大84.3%,而横桥向仅墩底区域塑性铰形成概率较大且与只考虑地震动随机性确定的塑性铰区域长度基本一致。塑性铰形成概率分析法,可以更加准确地对RC高墩的塑性铰形成和分布做出评估。
In order to study probability of plastic hinge formation of a reinforced concrete(RC) high pier under near-field seismic action, a certain RC high pier with a height of 90 m was taken as the study object. Firstly, the support vector machine algorithm was used to predict the equivalent yield curvature of its cross section. Then, considering pier parameters and the randomness of near-field seismic action, the software OpenSees was used to build the high pier model to do the increment dynamic nonlinear analysis. Finally, the equivalent yield curvature was taken as the critical index, and dynamic responses of the pier's cross section were equivalently normalized with JC method to calculate and analyze the probability of plastic hinge formation of the pier's cross section. The results showed that equivalent yield curvature of RC high pier cross section in forward bridge direction and that in transverse bridge one have obvious discreteness and obey normal distribution; under near-field seismic action in forward bridge direction, probabilities of plastic hinge formation in pier bottom area and pier middle part are larger to form plastic hinges, plastic hinge length in pier middle part is 31.7 m and 84.3% longer than that determined only considering the randomness of seismic action; under the near-field seismic action in transverse bridge direction, probability of plastic hinge formation in pier bottom area is larger, and plastic hinge length is basically consistent to that determined only considering the randomness of seismic action; the probability analysis method for plastic hinge formation can be used to more accurately evaluate plastic hinge formation and distribution of RC high-piers.
In order to study probability of plastic hinge formation of a reinforced concrete(RC) high pier under near-field seismic action, a certain RC high pier with a height of 90 m was taken as the study object. Firstly, the support vector machine algorithm was used to predict the equivalent yield curvature of its cross section. Then, considering pier parameters and the randomness of near-field seismic action, the software OpenSees was used to build the high pier model to do the increment dynamic nonlinear analysis. Finally, the equivalent yield curvature was taken as the critical index, and dynamic responses of the pier's cross section were equivalently normalized with JC method to calculate and analyze the probability of plastic hinge formation of the pier's cross section. The results showed that equivalent yield curvature of RC high pier cross section in forward bridge direction and that in transverse bridge one have obvious discreteness and obey normal distribution; under near-field seismic action in forward bridge direction, probabilities of plastic hinge formation in pier bottom area and pier middle part are larger to form plastic hinges, plastic hinge length in pier middle part is 31.7 m and 84.3% longer than that determined only considering the randomness of seismic action; under the near-field seismic action in transverse bridge direction, probability of plastic hinge formation in pier bottom area is larger, and plastic hinge length is basically consistent to that determined only considering the randomness of seismic action; the probability analysis method for plastic hinge formation can be used to more accurately evaluate plastic hinge formation and distribution of RC high-piers.
引文
[1] 中华人民共和国交通运输部.公路桥梁抗震设计细则:JTG/T B02-01—2008[S].北京:人民交通出版社.2008.
[2] CERAVOLO R,DEMARIE G V,GIORDANO L,et al.Problems in applying code-specified capacity design procedures to seismic design of tall piers[J].Engineering Structures,2009,31(8):1811-1821.
[3] 梁智垚,李建中.桥梁高墩合理计算模型探讨[J].地震工程与工程振动,2007,27(2):91-98.LIANG Zhiyao,LI Jianzhong.Investigation on rational analytical model of tall bridge pier[J].Earthquake Engineering and Engineering Vibration,2007,27(2):91-98.
[4] 夏修身,陈兴冲,王常峰.铁路高墩弹塑性地震反应分析[J].世界地震工程,2008,24(2):117-121.XIA Xiushen,CHEN Xingchong,WANG Changfeng.Nonlinear seismic response of the tall RC piers of railway bridges[J].World Earthquake Engineering,2008,24(2):117-121.
[5] 何钦象,田小红,宋丹.高墩大跨径连续刚构桥抗震性能评估[J].振动与冲击,2009,28(1):68-71.HE Qinxiang,TIAN Xiaohong,SONG Dan.A seismic performance evaluation of a long-span continuous rigid frame bridge with tall piers[J].Journal of Vibration and Shock,2009,28(1):68-71.
[6] 卢皓,管仲国,李建中.高阶振型对高墩桥梁抗震性能的影响及其识别[J].振动与冲击,2012,31(17):81-86.LU Hao,GUAN Zhongguo,LI Jianzhong.Effect of higher modal shapes on aseismic performance of a bridge with high piers and its identification[J].Journal of Vibration and Shock,2012,31(17):81-86.
[7] 陈旭,李建中,刘笑显.墩身高阶振型对高墩地震反应影响[J].同济大学学报(自然科学版),2017,45(2):159-166.CHEN Xu,LI Jianzhong,LIU Xiaoxian.Seismic performance of tall piers influenced by high-mode effects of piers[J].Journal of Tongji University (Natural Science),2017,45(2):159-166.
[8] YASSIN M H M.Nonlinear analysis of prestressed concrete structures under monotonic and cycling loads[D].Berkeley:University of California,1994.
[9] 日本道路协会.道桥示方书·同解说·Ⅴ耐震设计篇[S].2012.
[10] FILIPPOU F C,POPOV E P,BERTERO V V.Effects of bond deterioration on hysteretic behavior of reinforced concrete joints[R].Berkeley:Earthquake Engineering Research Center,University of California,1983.
[11] 扶长生.抗震工程学-理论与实践[M].北京:中国建筑工业出版社,2013.
[12] 吕大刚,于晓辉,潘峰,等.基于改进云图法的结构概率地震需求分析[J].世界地震工程,2010,26(1):7-15.Lü Dagang,YU Xiaohui,PAN Feng,et al.Probabilistic seismic demand analysis of structures based on an improved cloud method[J].World Earthquake Engineering,2010,26(1):7-15.
[13] ELLINGWOOD B,GALAMBOS T V,MACGREGOR J G,et al.Development of a probability based load criterion for American national standard A58-Building code requirements for minimum design loads in building and other structures[M].Washington DC:National Bureau of Standards,1980.
[14] Joint Committee on Structural Safety.Probabilistic modal code[M/OL].Internet publication,http://www.jcss.eth.ch.2011.
[15] 吴文鹏.考虑不确定性的钢筋混凝土桥梁地震易损性研究[D].长沙:湖南大学,2015.
[16] 马文英,周玉娟.地震荷载动力分析与工程结构可靠度设计原理[M].北京:中国水利水电出版社,2009.
[17] 中华人民共和国住房与城乡建设部.混凝土结构设计规范:GB 50010—2010[S].北京:中国建筑工业出版社,2010.
[18] NIELSON B G.Analytical fragility curves for highway bridges in moderate seismic zones[D].Atlanta,GA:Georgia Institute of Technology,2005.
[19] 杨庆山,田玉基.地震地面运动及其人工合成[M].北京:科学出版社,2014.
[20] SHASHI S,BAKER J.Pulse classifications from NGA West2 database[DB/OL].2012.https://web.stanford.edu/～bakerjw/pulse_classification_v2/Pulse-like-records.html.
[21] 赵国藩.高等钢筋混凝土结构学[M].北京:机械工业出版社,2016.
[22] 赵金钢,赵人达,占玉林,等.基于支持向量机和蒙特卡洛法的结构随机灵敏度分析方法[J].工程力学,2014,31(2):195-202.ZHAO Jingang,ZHAO Renda,ZHAN Yulin,et al.Stochastic sensitivity analysis method based on support vector machine and Monte Carlo[J].Engineering Mechanics,2014,31(2):195-202.
[2] CERAVOLO R,DEMARIE G V,GIORDANO L,et al.Problems in applying code-specified capacity design procedures to seismic design of tall piers[J].Engineering Structures,2009,31(8):1811-1821.
[3] 梁智垚,李建中.桥梁高墩合理计算模型探讨[J].地震工程与工程振动,2007,27(2):91-98.LIANG Zhiyao,LI Jianzhong.Investigation on rational analytical model of tall bridge pier[J].Earthquake Engineering and Engineering Vibration,2007,27(2):91-98.
[4] 夏修身,陈兴冲,王常峰.铁路高墩弹塑性地震反应分析[J].世界地震工程,2008,24(2):117-121.XIA Xiushen,CHEN Xingchong,WANG Changfeng.Nonlinear seismic response of the tall RC piers of railway bridges[J].World Earthquake Engineering,2008,24(2):117-121.
[5] 何钦象,田小红,宋丹.高墩大跨径连续刚构桥抗震性能评估[J].振动与冲击,2009,28(1):68-71.HE Qinxiang,TIAN Xiaohong,SONG Dan.A seismic performance evaluation of a long-span continuous rigid frame bridge with tall piers[J].Journal of Vibration and Shock,2009,28(1):68-71.
[6] 卢皓,管仲国,李建中.高阶振型对高墩桥梁抗震性能的影响及其识别[J].振动与冲击,2012,31(17):81-86.LU Hao,GUAN Zhongguo,LI Jianzhong.Effect of higher modal shapes on aseismic performance of a bridge with high piers and its identification[J].Journal of Vibration and Shock,2012,31(17):81-86.
[7] 陈旭,李建中,刘笑显.墩身高阶振型对高墩地震反应影响[J].同济大学学报(自然科学版),2017,45(2):159-166.CHEN Xu,LI Jianzhong,LIU Xiaoxian.Seismic performance of tall piers influenced by high-mode effects of piers[J].Journal of Tongji University (Natural Science),2017,45(2):159-166.
[8] YASSIN M H M.Nonlinear analysis of prestressed concrete structures under monotonic and cycling loads[D].Berkeley:University of California,1994.
[9] 日本道路协会.道桥示方书·同解说·Ⅴ耐震设计篇[S].2012.
[10] FILIPPOU F C,POPOV E P,BERTERO V V.Effects of bond deterioration on hysteretic behavior of reinforced concrete joints[R].Berkeley:Earthquake Engineering Research Center,University of California,1983.
[11] 扶长生.抗震工程学-理论与实践[M].北京:中国建筑工业出版社,2013.
[12] 吕大刚,于晓辉,潘峰,等.基于改进云图法的结构概率地震需求分析[J].世界地震工程,2010,26(1):7-15.Lü Dagang,YU Xiaohui,PAN Feng,et al.Probabilistic seismic demand analysis of structures based on an improved cloud method[J].World Earthquake Engineering,2010,26(1):7-15.
[13] ELLINGWOOD B,GALAMBOS T V,MACGREGOR J G,et al.Development of a probability based load criterion for American national standard A58-Building code requirements for minimum design loads in building and other structures[M].Washington DC:National Bureau of Standards,1980.
[14] Joint Committee on Structural Safety.Probabilistic modal code[M/OL].Internet publication,http://www.jcss.eth.ch.2011.
[15] 吴文鹏.考虑不确定性的钢筋混凝土桥梁地震易损性研究[D].长沙:湖南大学,2015.
[16] 马文英,周玉娟.地震荷载动力分析与工程结构可靠度设计原理[M].北京:中国水利水电出版社,2009.
[17] 中华人民共和国住房与城乡建设部.混凝土结构设计规范:GB 50010—2010[S].北京:中国建筑工业出版社,2010.
[18] NIELSON B G.Analytical fragility curves for highway bridges in moderate seismic zones[D].Atlanta,GA:Georgia Institute of Technology,2005.
[19] 杨庆山,田玉基.地震地面运动及其人工合成[M].北京:科学出版社,2014.
[20] SHASHI S,BAKER J.Pulse classifications from NGA West2 database[DB/OL].2012.https://web.stanford.edu/～bakerjw/pulse_classification_v2/Pulse-like-records.html.
[21] 赵国藩.高等钢筋混凝土结构学[M].北京:机械工业出版社,2016.
[22] 赵金钢,赵人达,占玉林,等.基于支持向量机和蒙特卡洛法的结构随机灵敏度分析方法[J].工程力学,2014,31(2):195-202.ZHAO Jingang,ZHAO Renda,ZHAN Yulin,et al.Stochastic sensitivity analysis method based on support vector machine and Monte Carlo[J].Engineering Mechanics,2014,31(2):195-202.