張耀庭+杜曉菊+楊力
摘 要:首先根據(jù)鋼筋混凝土柱的擬靜力試驗(yàn)結(jié)果,探討王東升的修正Park-Ang模型的適用性;然后基于構(gòu)件層次的結(jié)構(gòu)損傷指標(biāo)為地震需求參數(shù),對鋼筋混凝土框架結(jié)構(gòu)進(jìn)行了基于IDA的易損性分析,并結(jié)合基于最大層間位移角的分析結(jié)果,探討了結(jié)構(gòu)基于損傷的抗震性能評估方法的可行性.結(jié)果表明:王東升提出的修正Park-Ang模型考慮了加載路徑的影響,能較準(zhǔn)確地反映首次超越破壞后累積損傷的發(fā)展過程,且總體上判別試件損傷狀態(tài)的準(zhǔn)確性相對較高;基于損傷的IDA能較好地反映整體結(jié)構(gòu)及局部的損傷發(fā)展過程、結(jié)構(gòu)的失效破壞機(jī)制,能準(zhǔn)確地判別結(jié)構(gòu)的薄弱環(huán)節(jié),但結(jié)構(gòu)損傷指標(biāo)會(huì)產(chǎn)生超出1.0的情況,不能很好地體現(xiàn)損傷指標(biāo)原始定義的基本含義;相較結(jié)構(gòu)基于最大層間位移角的抗震性能評估結(jié)果,基于結(jié)構(gòu)損傷的抗震性能評估方法綜合考慮了結(jié)構(gòu)的響應(yīng)與自身的能力,更全面地評估了結(jié)構(gòu)的性能水準(zhǔn),能預(yù)測結(jié)構(gòu)在不同地震強(qiáng)度下各性能狀態(tài)的失效概率.
關(guān)鍵詞:鋼筋混凝土框架;修正Park-Ang損傷模型;增量動(dòng)力分析;易損性分析;柱擬靜力試驗(yàn)
中圖分類號:TU375 文獻(xiàn)標(biāo)識碼:A
文章編號:1674-2974(2016)05-0009-13
Abstract:This paper study discussed the applicability of Park-Ang model modified by Wang based on the pseudo-static test results of reinforced concrete columns. The structural damage index based on the component level was selected, and both the incremental dynamic analysis and fragility analysis of the reinforced concrete frame were conducted. Additionally, the prediction by the modified method to evaluate the seismic performance in terms of the damage index of the RC frame was compared with the maximum inter-story drift ratio of the fragility analysis result. The analysis results show that the modified Park-Ang model that considers the loading path effect predicts well the cumulative damage process after the first damage, which discriminates the specimen damage status accurately, the damage development process, and the overall and local failure mechanism. Further, the weak links can be accurately distinguished. However, the damage index higher than 1.0 may be caused by using these methods, which cannot accurately reflect the basic meaning of the original definition. Compared with the maximum inter-story drift ratio, the seismic performance evaluation method using the damage index considers the structural response and properties. The modified method can be used to evaluate the structural performance more comprehensively and predict the failure probability of the structures under different earthquake loads.
Key words:reinforced concrete frame; fixed Park-Ang damage model; incremental dynamic analysis; fragility analysis; pseudo-static test of columns
隨著基于性能的抗震設(shè)計(jì)理論與損傷模型研究的發(fā)展,通過損傷模型來量化結(jié)構(gòu)性能指標(biāo),實(shí)現(xiàn)基于損傷的抗震性能評估方法將成為必然.目前,基于鋼筋混凝土結(jié)構(gòu)在地震作用下的兩種破壞模式,國內(nèi)外學(xué)者采用不同的響應(yīng)參數(shù)建立了各種各樣的損傷模型,包括基于變形、退化、能量、低周疲勞及其組合形式的損傷模型,但沒有一個(gè)統(tǒng)一、普遍適用的損傷模型.其中,基于變形與能量的Park-Ang損傷模型在地震工程領(lǐng)域中得到較多的應(yīng)用和研究,根據(jù)該模型的缺陷與不足,Kunnath[[1]、Kumar[[2]、Chai[[3]、歐進(jìn)萍[[4]、牛荻濤[[5]和呂大剛[[6]等學(xué)者從不同角度對其進(jìn)行了修正和改進(jìn).本文首先根據(jù)鋼筋混凝土柱的擬靜力試驗(yàn)結(jié)果,探討王東升的修正Park-Ang模型[[7]的適用性.然后,以結(jié)構(gòu)損傷指標(biāo)為地震需求參數(shù),對鋼筋混凝土框架結(jié)構(gòu)進(jìn)行了基于IDA方法的易損性分析,并結(jié)合基于最大層間位移角的分析結(jié)果,探討了結(jié)構(gòu)基于損傷的抗震性能評估方法的可行性.