摘要
以三跨六层钢筋混凝土框架为例 ,用本文第二作者编制并经检验的平面框架非弹性动力反应分析程序 PL -AFJD对严格按国家标准 GBJ1 0 -89设计的柱截面尺寸控制偏紧且沿高度方向有一次截面变化的 7、8、9度区的框架做了罕遇地震作用下的多波输入分析。分析结果表明 ,7度区结构的反应较小 ,处在结构可以承受的范围内 ,虽仍有部分柱端屈服 ,但非弹性变形不严重。 9度区虽然反应较大 ,但绝大部分柱端的反应均在构件滞回变形能力范围之内 ,且未发现明显形成薄弱层的趋势。情况较为严重的是 8度区框架 ,其中虽未形成明显的薄弱层 ,但在某些地震动输入下 ,少数柱端变形已接近柱的非弹性滞回变形能力界限 ,预示了局部倒塌的可能性。分析结果初步揭示了三个不同烈度区抗震规定有效性的差异 。
With examples of three 6-storey RC frames by using an elasto-plastic dynamic analysis program PL-AFJD of plane frame, developed by the second author of this paper, the frames designed for different earthquake-intensity regions (intensity category 7, 8, 9 respectively) are analyzed nonlinearly under four ground motions at the action of rare earthquake. Three frames strictly conform to the National Standard GBJ10-89 and the dimensions of columns are changed once along the height. The structure designed on intensity category 7 shows a relatively small response, which could be sustained by the structure. Though the hinge formation in columns can not be prevented, the inelastic deformation of columns is not serious, the structure at intensity category 9 exhibits a relative strong response, but the deformation of most columns is within the capacity and the trend to form a soft-storey does not appear. It is the structure at intensity category 8 that shows a severe response. Though the visible soft-storey can not be found, the deformation of some columns is beyond the capacity of inelastic hysteretic deformation under certain inputs, which indicate the possibility of local collapse.The elementary analysis results demonstrate the different effectiveness of seismic provisions for three different earthquake-intensity regions, which may be a reference to the amendment of National Design Standard.
出处
《重庆建筑大学学报》
CSCD
2001年第6期1-9,48,共10页
Journal of Chongqing Jianzhu University
基金
国家自然科学基金资助项目 (5 98780 5 6 )
