本文選題：基礎(chǔ)隔震結(jié)構(gòu)　切入點(diǎn)：反應(yīng)譜　出處：《蘭州理工大學(xué)》2016年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：基礎(chǔ)隔震技術(shù)在過(guò)去二十多年來(lái)經(jīng)歷了多場(chǎng)大地震考驗(yàn),成為國(guó)內(nèi)外最熱門(mén)的一項(xiàng)抗震技術(shù),并且在包括我國(guó)在內(nèi)的多個(gè)國(guó)家進(jìn)入大面積推廣階段。反應(yīng)譜對(duì)認(rèn)識(shí)結(jié)構(gòu)地震響應(yīng)規(guī)律、校核結(jié)構(gòu)分析結(jié)果有著重要的作用。反應(yīng)譜的平均特性與震源機(jī)制,場(chǎng)地條件,震級(jí),震中距等眾多因素有關(guān)。其中,震源機(jī)制作為地震動(dòng)的影響因素,不僅能夠影響反應(yīng)譜的譜值還能夠影響反應(yīng)譜曲線的形狀,進(jìn)而在結(jié)構(gòu)的抗震設(shè)計(jì)中起到重要的作用。因此,本文圍繞震源機(jī)制對(duì)隔震結(jié)構(gòu)反應(yīng)譜的影響展開(kāi)了以下幾方面的工作:(1)采用雙自由度體系分析模型,研究譜的類(lèi)型及上部結(jié)構(gòu)阻尼比對(duì)隔震結(jié)構(gòu)反應(yīng)譜的影響。以ATC-63報(bào)告建議的選取原則選取了22條地震記錄,以此為激勵(lì),利用狀態(tài)空間法建立了隔震層的真譜與擬譜,并通過(guò)改變上部結(jié)構(gòu)的阻尼比建立了不同阻尼比的反應(yīng)譜。對(duì)比分析后,結(jié)果表明在研究隔震結(jié)構(gòu)的反應(yīng)譜時(shí),不可用擬譜來(lái)代替真譜;以及在建立隔震結(jié)構(gòu)的反應(yīng)譜時(shí),需確定上部結(jié)構(gòu)的材料,從而確定上部結(jié)構(gòu)阻尼比;(2)采用非比例阻尼,研究震源機(jī)制對(duì)隔震結(jié)構(gòu)線彈性反應(yīng)譜的影響。在Ⅱ類(lèi)場(chǎng)地條件下,選取605條地震記錄作為統(tǒng)計(jì)樣本,按照地震記錄類(lèi)型及震源機(jī)制進(jìn)行分組,運(yùn)用狀態(tài)空間法得到了在近場(chǎng)及遠(yuǎn)場(chǎng)地震作用下的加速度、位移及能量反應(yīng)譜。采用標(biāo)準(zhǔn)化和平均化的方式研究了反應(yīng)譜的特性,并運(yùn)用分段線性擬合的方法給出了設(shè)計(jì)反應(yīng)譜的表達(dá)式,該表達(dá)式可以反映震源機(jī)制等因素對(duì)反應(yīng)譜的影響作用,最后通過(guò)對(duì)某實(shí)際基礎(chǔ)隔震工程進(jìn)行算例驗(yàn)證,將計(jì)算結(jié)果與抗震規(guī)范進(jìn)行對(duì)比,結(jié)果表明本文提出的表達(dá)式更為安全、合理,可將其應(yīng)用于基礎(chǔ)隔震結(jié)構(gòu)的抗震設(shè)計(jì)中;(3)采用Bouc-Wen模型描述隔震支座的非線性行為,研究震源機(jī)制對(duì)隔震結(jié)構(gòu)彈塑性反應(yīng)譜的影響。運(yùn)用狀態(tài)空間法及四階龍格-庫(kù)塔法得到近場(chǎng)及遠(yuǎn)場(chǎng)地震作用下的彈塑性反應(yīng)譜,對(duì)反應(yīng)譜特性進(jìn)行分析之后,運(yùn)用曲線擬合的方法給出了反應(yīng)比譜(彈塑性反應(yīng)譜與線彈性反應(yīng)譜譜值比與周期的關(guān)系)的表達(dá)式。該表達(dá)式可反映震源機(jī)制等因素對(duì)反應(yīng)譜的影響作用。利用該表達(dá)式可在線彈性反應(yīng)譜的基礎(chǔ)上快速獲得結(jié)構(gòu)的彈塑性響應(yīng)。最后通過(guò)有限元模型進(jìn)行了算理驗(yàn)證。結(jié)果表明:該式在進(jìn)行隔震結(jié)構(gòu)的彈塑性地震反應(yīng)分析時(shí)具有良好的計(jì)算精度。
[Abstract]:In the past 20 years, the foundation isolation technology has been tested by many large earthquakes, and has become the most popular seismic technology at home and abroad. The response spectrum plays an important role in recognizing the seismic response law of structures and checking the results of structural analysis. The average characteristics of response spectra and the focal mechanism, site conditions, magnitude, etc. The focal mechanism, as an influential factor of ground motion, can not only affect the spectral value of the response spectrum but also the shape of the response spectrum curve, and thus play an important role in the seismic design of the structure. In this paper, according to the effect of focal mechanism on response spectrum of isolated structures, the following work is carried out: 1) A two-degree-of-freedom system analysis model is used. The types of spectrum and the effect of damping ratio of superstructure on response spectrum of isolated structures are studied. Based on the selection principle of ATC-63 report, 22 seismic records are selected, and the true spectrum and pseudo-spectrum of isolation layer are established by state space method. By changing the damping ratio of superstructure, the response spectra of different damping ratios are established. The results show that pseudo spectrum can not be used instead of true spectrum when studying the response spectrum of isolated structure, and when the response spectrum of isolated structure is established, the response spectrum of isolated structure can not be replaced by pseudo spectrum. The material of superstructure should be determined, and the damping ratio of superstructure should be determined by adopting non-proportional damping. The effect of focal mechanism on the linear elastic response spectrum of isolated structures is studied. 605 seismic records are selected as statistical samples under the condition of class 鈪，

本文編號(hào)：1628342