資源描述:
《基于小波函數(shù)的地震動(dòng)反應(yīng)譜擬合方法》由會(huì)員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在教育資源-天天文庫。
1、基于小波函數(shù)的地震動(dòng)反應(yīng)譜擬合方法張郁山趙鳳新(中國地震災(zāi)害防御中心,北京100029)摘要:提出一種改進(jìn)的基于小波函數(shù)的地震動(dòng)反應(yīng)譜擬合方法,該方法通過調(diào)整給定地震動(dòng)加速度時(shí)程,使其反應(yīng)譜以一定精度擬合目標(biāo)譜。首先,構(gòu)造一種用于校正的增量加速度小波函數(shù),該函數(shù)具有兩個(gè)特點(diǎn):①在反應(yīng)譜的某個(gè)固定控制周期點(diǎn)處,對該函數(shù)進(jìn)行時(shí)移和線性調(diào)幅處理后,將其疊加在初始地震動(dòng)時(shí)程上,所得地震動(dòng)時(shí)程在該控制周期點(diǎn)處的反應(yīng)譜值與目標(biāo)值精確相等;②由該函數(shù)積分得到的增量速度和增量位移曲線不出現(xiàn)基線漂移,從而保證將其疊加在初始地震動(dòng)上不會(huì)產(chǎn)生附加的基線漂移。
2、其次,基于該小波函數(shù),提出迭代調(diào)整方法,以消除反應(yīng)譜不同控制周期點(diǎn)之間的耦合效應(yīng),實(shí)現(xiàn)對整個(gè)目標(biāo)譜的擬合。數(shù)值算例表明,該方法合成的地震動(dòng)時(shí)程不僅能夠以較高的精度擬合目標(biāo)譜,而且能夠保留初始天然地震動(dòng)的基本特征,從而能夠確保結(jié)構(gòu)地震反應(yīng)分析結(jié)果的合理性與可靠性。此外,該方法具有較快的收斂速度,能夠通過有限幾步迭代調(diào)整實(shí)現(xiàn)較高的擬合精度。關(guān)鍵詞:抗震設(shè)計(jì);結(jié)構(gòu)地震反應(yīng);反應(yīng)譜;時(shí)程分析;地震動(dòng)合成中圖分類號:P315.9文獻(xiàn)標(biāo)識碼:A文章編號:1000-131X(2014)01-0070-12Matchingmethodofground-
3、motionresponsespectrumbasedonthewaveletfunctionZhangYushanZhaoFengxin(ChinaEarthquakeDisasterPreventionCenter,Beijing100029,China)Abstract:Animprovedwavelet-basedspectralmatchingmethodisproposedtomodifygivengroundmotiontomakeitsresponsespectrummatchthetargetspectrummorep
4、recisely.Anincrementalaccelerationwaveletfunctionisconstructedwithfollowingtwoproperties:①atsomecontrollingperiodofresponsespectrum,afterbeingtime-shiftedandlinear-scaled,thewaveletcanbesuperimposedontotheinitialgroundmotiontogenerateanewonewhosespectrumisequaltothetarge
5、tvalueatthiscontrollingperiod;②theincrementalvelocityanddisplacementobtainedbyintegratingthewaveletdonotexhibitbaselinedrift,thusthereisnoadditionalbaselinedriftwhensuperimposingitontotheinitialgroundmotion.Basedonthewavelet,aniterativemodificationmethodisproposedtoelimi
6、natethecouplingeffectsamongdifferentcontrollingperiodsofresponsespectrumtorealizethematchingofwholetargetspectrum.Numericalresultsshowthatthegroundmotionsynthesizedbythemethodcannotonlymatchthetargetspectrumwithrelativelyhighprecision,butalsoretainthebasicfeaturesoforigi
7、nalnaturalgroundmotion,sotherationalityandreliabilityofanalysisofstructuraldynamicresponsescanbeensured.Inaddition,theproposedmethodcanrealizehighmatchingprecisionwithlimitediterations.Keywords:aseismicdesign;structuraldynamicresponse;responsespectrum;time-historyanalysi
8、s;ground-motionsynthesisE-mail:hyszhang@163.com引言各類重大工程結(jié)構(gòu)的抗震設(shè)計(jì),如核電廠中的I類物項(xiàng)[1]、水電站中的重要雍水建筑[2]、大型儲(chǔ)液基金項(xiàng)目:北京