對中震不屈服設(shè)防目標(biāo)的討論
扶長生，張小勇，朱鳳濤
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(上海長福工程結(jié)構(gòu)設(shè)計事務(wù)所，上海 200011)［摘要］關(guān)鍵構(gòu)件中震彈性或中震不屈服的設(shè)防目標(biāo)，作為一種加強措施在抗震設(shè)計中已經(jīng)得到了應(yīng)用。然而，工程實踐表明按小震不壞設(shè)計得到的截面配筋率有時往往要大于中震不屈服的配筋率。在詳細(xì)剖析有地震效應(yīng)荷載組合公式的基礎(chǔ)上，用圖表和工程實例說明了中震不屈服對截面配筋的影響。從抗震承載力調(diào)整系數(shù)γRE，線性疊加原理和以概率理論為基礎(chǔ)的設(shè)計極限狀態(tài)等方面，對中震不屈服做出進(jìn)一步評價。目前工程界采用小震彈性分析，中震放大系數(shù)和荷載效應(yīng)組合來實現(xiàn)薄弱部位或重要部位構(gòu)件中震不屈服的設(shè)計方法，與當(dāng)前的抗震設(shè)計理論是有矛盾的。中震不屈服是中震可修設(shè)防目標(biāo)中的一種狀態(tài)，表示震后建筑物恢復(fù)使用需要修理的程度。結(jié)構(gòu)工程師應(yīng)采用非線性分析驗算構(gòu)件中震時是否屈服。［關(guān)鍵詞］建筑抗震；小震彈性；小震不壞;中震不屈服Discussion on the target objective of design-earthquake-unyieldingFu Changsheng, Zhang Xiaoyong, Zhu Fengtao(Shanghai CHINAFU Structural Design Inc.,Shanghai 200011,China)Abstract:Currently, the target objective of unyielding during the design earthquake is defined and has got application to the key components in seismic design, as the measurement to enhance their strength. The target is reached by using the method of the load combination and the magnification factor equal to the ratio of the design earthquake and minor earthquake effects. Analysis results of the engineering projective show that the reinforcement contents may be unexpectedly less than those obtained by the method called un-damage during the minimum considered earthquake which is recommended by Chinese codes. This was explained in detail by using charts obtained from the formulae of load combination stipulated in GB50011—2001 and JGJ93—2002. The definition was discussed from the viewpoints such as the adjusting factor for seismic bearing capacity γRE, the principle of linear superposition and design theory of ultimate state. The above concept of design-earthquake-unyielding of key components does not comply with Chinese seismic design theory. In fact, it is the performance point B in the performance curves defined by ATC-40 or ASCE 41-06, which should be assessed using non-linear analysis method, static or dynamic.Keywords:seismic building; elasticity; un-damage in minimum considered earthquake; unyielding in design earthquake作者簡介：扶長生，教授級高工，董事長，Email:cfstruct@vip.sina.com。參考文獻(xiàn)［1］徐培福. 復(fù)雜高層建筑結(jié)構(gòu)設(shè)計［M］. 北京: 中國建筑工業(yè)出版社, 2005.［2］GB50011—2001 建筑抗震設(shè)計規(guī)范［S］.北京：中國建筑工業(yè)出版社，2001.［3］JGJ3—2002 高層建筑混凝土結(jié)構(gòu)技術(shù)規(guī)程［S］.北京：中國建筑工業(yè)出版社，2002.［4］GB50068—2001 建筑結(jié)構(gòu)可靠度設(shè)計統(tǒng)一標(biāo)準(zhǔn)［S ］.北京：中國建筑工業(yè)出版社，2001.
［5］CECS160：2004 建筑工程抗震性態(tài)設(shè)計通則(試用)［S］.2004.
［6］葉列平，錢稼茹. 關(guān)于取消承載力抗震調(diào)整系數(shù)γRE的意見［C］∥第九屆高層建筑抗震技術(shù)交流會論文集，2003：157-163.
