长周期抗震设计反应谱衰减指数与阻尼修正系数研究
|
摘要
对基于地震惯性力的绝对加速度谱和基于滞回恢复力的拟加速度谱进行差异解析,分析了长周期地震动拟加速度谱的衰减指数及其阻尼修正系数谱的变化规律。筛选长周期分量丰富的破坏性浅源强震数字化记录,通过弹性反应谱分析研究拟加速度动力放大系数谱的特征周期、两个下降段的衰减指数以及阻尼修正系数。分析结果表明:基于结构承载力的抗震设计谱应以基于滞回恢复力的拟加速度谱进行标定,以基于惯性力的绝对加速度谱标定对大阻尼比长周期结构的抗震设计偏于保守。拟加速度谱与绝对加速度谱在长周期段的衰减规律不同,大阻尼比长周期段拟加速度谱衰减速度较快。阻尼比0.05的标准抗震设计谱在第一和第二下降段采用形式简单的1/T和1/T2的规律衰减是合理可行的,无需通过修正衰减指数获得基于拟加速度的大阻尼比抗震设计谱。长周期地震反应谱的动力放大系数有显著的场地效应,以Ⅱ类场地为参考,Ⅰ~Ⅳ类场地效应系数分别取0.9、1.0、1.1和1.2较合适。地震动长周期分量对结构阻尼修正系数有很大的影响,基于拟加速度谱与绝对加速度谱的阻尼修正系数在长周期段有显著的差异。结构算例验证了长周期结构建议设计谱的衰减指数与阻尼修正系数取值的合理性。
The difference between absolute-acceleration response spectrum( ARS) based on the earthquake inertia force and quasi-acceleration response spectrum( QRS) based on the hysteretic restoring force of the structure were explained,and the variation rule of the attenuation power index and the damping reduction factor of the QRS for longperiod ground motions were studied. The digital ground motion records with rich long-period components from destructive shallow earthquake were selected,and the elastic response spectrum analysis method was employed to calculate the characteristic period,the attenuation power indexes of curvilinear decrease sections and the damping reduction factor of the dynamic amplification factor spectrum based on the QRS. The results show that the seismic design spectrum based on the bearing capacity should suitably be calibrated by the QRS based on the hysteretic restoring force of the structure,and the design spectrum calibrated by the ARS based on the earthquake inertia force might lead to rather conservative seismic design for the long-period structures with high damping ratio. The attenuation trend of curvilinear long-period section of the ARS is different from that of the QRS which attenuates comparatively fast for the structures with high damping ratio. It is rational and feasible for the standard seismic design spectrum based on the QRS with 5% damping ratio to adopt the simple attenuation rule in the first and second decrease section,namely1/T and 1/T2,respectively,and also the QRS with high damping ratio can be obtained and does not need to reduce the attenuation power index. The dynamic amplification factor of the long-period seismic response spectrum has significant site effects,and it is well suitable for the site class Ⅰ,site class Ⅱ,site class Ⅲ and site class Ⅳ to use0. 9,1. 0,1. 1 and 1. 2,respectively,serving as the site effect factors and referring to the site class Ⅱ level. The long-period components of ground motions have a great influence on the damping reduction factors,and the damping reduction factors based on the QRS are significantly different from the damping reduction factors based on the ARS in the long-period section. Numerical engineering example validates the rationality of attenuation power index and damping reduction factor of the proposed design spectrum for long-period structures.
The difference between absolute-acceleration response spectrum( ARS) based on the earthquake inertia force and quasi-acceleration response spectrum( QRS) based on the hysteretic restoring force of the structure were explained,and the variation rule of the attenuation power index and the damping reduction factor of the QRS for longperiod ground motions were studied. The digital ground motion records with rich long-period components from destructive shallow earthquake were selected,and the elastic response spectrum analysis method was employed to calculate the characteristic period,the attenuation power indexes of curvilinear decrease sections and the damping reduction factor of the dynamic amplification factor spectrum based on the QRS. The results show that the seismic design spectrum based on the bearing capacity should suitably be calibrated by the QRS based on the hysteretic restoring force of the structure,and the design spectrum calibrated by the ARS based on the earthquake inertia force might lead to rather conservative seismic design for the long-period structures with high damping ratio. The attenuation trend of curvilinear long-period section of the ARS is different from that of the QRS which attenuates comparatively fast for the structures with high damping ratio. It is rational and feasible for the standard seismic design spectrum based on the QRS with 5% damping ratio to adopt the simple attenuation rule in the first and second decrease section,namely1/T and 1/T2,respectively,and also the QRS with high damping ratio can be obtained and does not need to reduce the attenuation power index. The dynamic amplification factor of the long-period seismic response spectrum has significant site effects,and it is well suitable for the site class Ⅰ,site class Ⅱ,site class Ⅲ and site class Ⅳ to use0. 9,1. 0,1. 1 and 1. 2,respectively,serving as the site effect factors and referring to the site class Ⅱ level. The long-period components of ground motions have a great influence on the damping reduction factors,and the damping reduction factors based on the QRS are significantly different from the damping reduction factors based on the ARS in the long-period section. Numerical engineering example validates the rationality of attenuation power index and damping reduction factor of the proposed design spectrum for long-period structures.
引文
[1]建筑抗震设计规范:GB 50011—2010[S].北京:中国建筑工业出版社,2010.(Code for seismic design of buildings:GB 50011—2010[S].Beijing:China Architecture&Building Press,2010.(in Chinese))
[2]方小丹,魏琏,周靖.长周期结构地震反应的特点与反应谱[J].建筑结构学报,2014,35(3):16-23.(FANG Xiaodan,WEI Lian,ZHOU Jing.Characteristics of earthquake response for long-period structure and response spectrum[J].Journal of Building Structures,2014,35(3):16-23.(in Chinese))
[3]王君杰,范立础.规范反应谱长周期部分修正方法的探讨[J].土木工程学报,1998,31(6):49-55.(WANG Junjie,FAN Lichu.Modification of code response spectrum in long-period phase[J].China Civil Engineering Journal,1998,31(6):49-55.(in Chinese))
[4]俞言祥,胡聿贤.关于上海市《建筑抗震设计规程》中长周期设计反应谱的讨论[J].地震工程与工程振动,2000,20(1):27-34.(YU Yanxiang,HU Yuxian.Discussion on the long-period design spectrum in‘Seismic design code for buildings’of Shanghai[J].Journal of Earthquake Engineering and Engineering Vibration,2000,20(1):27-34.(in Chinese))
[5]陈勇,俞言祥.《建筑抗震设计规范》(GB 50011—2001)中多阻尼比反应谱长周期区段的适用性[J].中国地震,2007,23(2):131-140.(CHEN Yong,YU Yanxiang.Adaptability of long-period portion of multi-damping-ratio-spectra in the code for seismic design of buildings(GB 50011—2001)[J].Earthquake Research in China,2007,23(2):131-140.(in Chinese))
[6]曹加良,施卫星,刘文光,等.长周期结构相对位移反应谱研究[J].振动与冲击,2011,30(7):63-70.(CAO Jialiang,SHI Weixing,LIU Wenguang,et al.Relative displacement response spectrum of a longperiod structure[J].Journal of Vibration and Shock,2011,30(7):63-70.(in Chinese))
[7]曹加良,施卫星,汪洋,等.我国抗震设计规范设计反应谱及谱阻尼折减系数研究[J].建筑结构学报,2011,32(9):34-43.(CAO Jialiang,SHI Weixing,WANG Yang,et al.Study on spectra and spectral damping reduction factors in Chinese seismic design codes[J].Journal of Building Structures,2011,32(9):34-43.(in Chinese))
[8]罗开海,王亚勇.关于不同阻尼比反应谱的研究[J].建筑结构,2011,41(11):16-21.(LUO Kaihai,WANG Yayong.Researches about the response spectra with different damping ratio[J].Building Structure,2011,41(11):16-21.(in Chinese))
[9]李恒,李龙安,冯谦.用位移反应谱研究长周期设计地震反应谱[J].地震工程与工程振动,2012,32(4):47-53.(LI Heng,LI Longan,FENG Qian.Seismic design spectra in long-period from spectral displacement analyses[J].Journal of Earthquake Engineering and Engineering Vibration,2012,32(4):47-53.(in Chinese))
[10]廖耘,容柏生,李盛勇.剪重比的本质关系推导及其对长周期超高层建筑的影响[J].建筑结构,2013,43(5):1-4.(LIAO Yun,RONG Baisheng,LI Shengyong.Derivation of shear-gravity ratio and its effect on long-period super high-rise building[J].Building Structure,2013,43(5):1-4.(in Chinese))
[11]蒋建,吕西林,周颖,蒋欢军.考虑场地类别的阻尼比修正系数研究[J].地震工程与工程振动,2009,29(1):153-161.(JIANG Jian,LU Xilin,ZHOU Ying,JIANG Huanjun.Research on modification factors of damping ratio considering site conditions[J].Journal of Earthquake Engineering and Engineering Vibration,2009,29(1):153-161.(in Chinese))
[12]LIN Y Y,CHANG K C.Study on damping reduction factor for buildings under earthquake ground motions[J].Journal of Structural Engineering,ASCE,2003,129(2):206-214.
[13]BOMMER J J,MENDIS R.Scaling of spectral displacement ordinates with damping ratios[J].Earthquake Engineering and Structural Dynamics,2005,34(2):145-165.
[14]LIN Y Y,MIRANDA E,CHANG K C.Evaluation of damping reduction factors for estimating elastic response of structures with high damping[J].Earthquake Engineering and Structural Dynamics,2005,34(11):1427-1443.
[15]HANCOCK J,BOMMER J J.A state-of-knowledge review of the influence of strong-motion duration on structural damage[J].Earthquake Spectra,2006,22(3):827-845.
[16]CAMERON W I,GREEN R A.Damping correction factors for horizontal ground motion response spectra[J].Bulletin of the Seismological Society of America,2007,97(3):934-960.
[17]STAFFORD P J,MENDIS R,BOMMER J J.Dependence of damping correction factors for response spectra on duration and number of cycles[J].Journal of Structural Engineering,ASCE,2008,34(8):1364-1373.
[18]PAOLUCCI R,ROVELLI A,FACCIOLI E,et al.On the reliability of long-period response spectral ordinates from digital accelerograms[J].Earthquake Engineering and Structural Dynamics,2008,37(5):697-710.
[19]CARDONE D,DOLCE M,RIVELLI M.Evaluation of reduction factors for high damping design response spectra[J].Bulletin of Earthquake Engineering,2009,7(1):273-291.
[20]HATZIGEORGIOU G D.Damping modification factors for SDOF systems subjected to near-fault,far-fault and artificial earthquakes[J].Earthquake Engineering and Structural Dynamics,2010,39(11):1239-1258.
[21]ZHOU J,TANG K,WANG H Y,FANG X D.Influence of ground motion duration on the damping reduction factor[J].Journal of Earthquake Engineering,2014,18(5):816-830.
[22]MOLLAIOLI F,LIBERATORE L,LUCCHINI A.Displacement damping modification factors for pulselike and ordinary records[J].Engineering Structures,2014,78:17-27.
[23]克拉克R W,彭津J.结构动力学[M].2版.北京:高等教育出版社,2006.(CLOUGH R W,PENZIEN J.Dynamics of structures[M].2nd ed.Beijing:Higher Education Press,2006.(in Chinese))
[24]International Code Council.International building code:IBC-2009[S].Country Club Hills,IL:International Code Council,2009:340-345.
[25]European Committee for Standardization.Design of structures for earthquake resistance:EC8-2004[S].Brussels,Belgium:CEN Technical Committee for Standardization,2004:33-40.
[26]周靖,方小丹,江毅.远场长周期地震动反应谱拐点特征周期研究[J].建筑结构学报,2015,36(6):1-12.(ZHOU Jing,FANG Xiaodan,JIANG Yi.Characteristic periods of response spectrum for far-field long-period seismic ground motions[J].Journal of Building Structures,2015,36(6):1-12.(in Chinese))
[27]Ministry of Vehicle,Infrastructure and Transport.Guidelines for calculation procedure and technical standard on seismically isolated structures:JPN-2001[S].Chiyoda-ku,Tokyo:Building Center of Japan,2001.
[28]NEWMARK N M,HALL W J.Earthquake spectra and design[R].Oakland,CA:Earthquake Engineering Research Center,1982:29-45.
[2]方小丹,魏琏,周靖.长周期结构地震反应的特点与反应谱[J].建筑结构学报,2014,35(3):16-23.(FANG Xiaodan,WEI Lian,ZHOU Jing.Characteristics of earthquake response for long-period structure and response spectrum[J].Journal of Building Structures,2014,35(3):16-23.(in Chinese))
[3]王君杰,范立础.规范反应谱长周期部分修正方法的探讨[J].土木工程学报,1998,31(6):49-55.(WANG Junjie,FAN Lichu.Modification of code response spectrum in long-period phase[J].China Civil Engineering Journal,1998,31(6):49-55.(in Chinese))
[4]俞言祥,胡聿贤.关于上海市《建筑抗震设计规程》中长周期设计反应谱的讨论[J].地震工程与工程振动,2000,20(1):27-34.(YU Yanxiang,HU Yuxian.Discussion on the long-period design spectrum in‘Seismic design code for buildings’of Shanghai[J].Journal of Earthquake Engineering and Engineering Vibration,2000,20(1):27-34.(in Chinese))
[5]陈勇,俞言祥.《建筑抗震设计规范》(GB 50011—2001)中多阻尼比反应谱长周期区段的适用性[J].中国地震,2007,23(2):131-140.(CHEN Yong,YU Yanxiang.Adaptability of long-period portion of multi-damping-ratio-spectra in the code for seismic design of buildings(GB 50011—2001)[J].Earthquake Research in China,2007,23(2):131-140.(in Chinese))
[6]曹加良,施卫星,刘文光,等.长周期结构相对位移反应谱研究[J].振动与冲击,2011,30(7):63-70.(CAO Jialiang,SHI Weixing,LIU Wenguang,et al.Relative displacement response spectrum of a longperiod structure[J].Journal of Vibration and Shock,2011,30(7):63-70.(in Chinese))
[7]曹加良,施卫星,汪洋,等.我国抗震设计规范设计反应谱及谱阻尼折减系数研究[J].建筑结构学报,2011,32(9):34-43.(CAO Jialiang,SHI Weixing,WANG Yang,et al.Study on spectra and spectral damping reduction factors in Chinese seismic design codes[J].Journal of Building Structures,2011,32(9):34-43.(in Chinese))
[8]罗开海,王亚勇.关于不同阻尼比反应谱的研究[J].建筑结构,2011,41(11):16-21.(LUO Kaihai,WANG Yayong.Researches about the response spectra with different damping ratio[J].Building Structure,2011,41(11):16-21.(in Chinese))
[9]李恒,李龙安,冯谦.用位移反应谱研究长周期设计地震反应谱[J].地震工程与工程振动,2012,32(4):47-53.(LI Heng,LI Longan,FENG Qian.Seismic design spectra in long-period from spectral displacement analyses[J].Journal of Earthquake Engineering and Engineering Vibration,2012,32(4):47-53.(in Chinese))
[10]廖耘,容柏生,李盛勇.剪重比的本质关系推导及其对长周期超高层建筑的影响[J].建筑结构,2013,43(5):1-4.(LIAO Yun,RONG Baisheng,LI Shengyong.Derivation of shear-gravity ratio and its effect on long-period super high-rise building[J].Building Structure,2013,43(5):1-4.(in Chinese))
[11]蒋建,吕西林,周颖,蒋欢军.考虑场地类别的阻尼比修正系数研究[J].地震工程与工程振动,2009,29(1):153-161.(JIANG Jian,LU Xilin,ZHOU Ying,JIANG Huanjun.Research on modification factors of damping ratio considering site conditions[J].Journal of Earthquake Engineering and Engineering Vibration,2009,29(1):153-161.(in Chinese))
[12]LIN Y Y,CHANG K C.Study on damping reduction factor for buildings under earthquake ground motions[J].Journal of Structural Engineering,ASCE,2003,129(2):206-214.
[13]BOMMER J J,MENDIS R.Scaling of spectral displacement ordinates with damping ratios[J].Earthquake Engineering and Structural Dynamics,2005,34(2):145-165.
[14]LIN Y Y,MIRANDA E,CHANG K C.Evaluation of damping reduction factors for estimating elastic response of structures with high damping[J].Earthquake Engineering and Structural Dynamics,2005,34(11):1427-1443.
[15]HANCOCK J,BOMMER J J.A state-of-knowledge review of the influence of strong-motion duration on structural damage[J].Earthquake Spectra,2006,22(3):827-845.
[16]CAMERON W I,GREEN R A.Damping correction factors for horizontal ground motion response spectra[J].Bulletin of the Seismological Society of America,2007,97(3):934-960.
[17]STAFFORD P J,MENDIS R,BOMMER J J.Dependence of damping correction factors for response spectra on duration and number of cycles[J].Journal of Structural Engineering,ASCE,2008,34(8):1364-1373.
[18]PAOLUCCI R,ROVELLI A,FACCIOLI E,et al.On the reliability of long-period response spectral ordinates from digital accelerograms[J].Earthquake Engineering and Structural Dynamics,2008,37(5):697-710.
[19]CARDONE D,DOLCE M,RIVELLI M.Evaluation of reduction factors for high damping design response spectra[J].Bulletin of Earthquake Engineering,2009,7(1):273-291.
[20]HATZIGEORGIOU G D.Damping modification factors for SDOF systems subjected to near-fault,far-fault and artificial earthquakes[J].Earthquake Engineering and Structural Dynamics,2010,39(11):1239-1258.
[21]ZHOU J,TANG K,WANG H Y,FANG X D.Influence of ground motion duration on the damping reduction factor[J].Journal of Earthquake Engineering,2014,18(5):816-830.
[22]MOLLAIOLI F,LIBERATORE L,LUCCHINI A.Displacement damping modification factors for pulselike and ordinary records[J].Engineering Structures,2014,78:17-27.
[23]克拉克R W,彭津J.结构动力学[M].2版.北京:高等教育出版社,2006.(CLOUGH R W,PENZIEN J.Dynamics of structures[M].2nd ed.Beijing:Higher Education Press,2006.(in Chinese))
[24]International Code Council.International building code:IBC-2009[S].Country Club Hills,IL:International Code Council,2009:340-345.
[25]European Committee for Standardization.Design of structures for earthquake resistance:EC8-2004[S].Brussels,Belgium:CEN Technical Committee for Standardization,2004:33-40.
[26]周靖,方小丹,江毅.远场长周期地震动反应谱拐点特征周期研究[J].建筑结构学报,2015,36(6):1-12.(ZHOU Jing,FANG Xiaodan,JIANG Yi.Characteristic periods of response spectrum for far-field long-period seismic ground motions[J].Journal of Building Structures,2015,36(6):1-12.(in Chinese))
[27]Ministry of Vehicle,Infrastructure and Transport.Guidelines for calculation procedure and technical standard on seismically isolated structures:JPN-2001[S].Chiyoda-ku,Tokyo:Building Center of Japan,2001.
[28]NEWMARK N M,HALL W J.Earthquake spectra and design[R].Oakland,CA:Earthquake Engineering Research Center,1982:29-45.