中国钢筋混凝土结构抗震措施优化的思路及示例

中国抗震设计规范与国外同类规范在处理各设防烈度区设计用地震作用相对水准与相应抗震措施严格程度的关系问题上存在实质性差异，为了弥补这种差异对结构抗震可能造成的不利影响，保证不同设防烈度区的结构具有基本一致的强震反应性态，以8度0．30g区二级抗震等级混凝土框架结构为例，完成了若干结构算例在罕遇地震水准的多条地面运动输入下的非弹性动力反应分析；对结构在强震下的反应性态进行了对比分析；初步探讨了中国规范延性抗震设计措施的优化方案．分析结果表明，在保持现行设计用地震作用相对水准不变的条件下，采用适当优化“强柱弱梁”措施及其他抗震构造措施的做法，可以使各设防烈度区结构在罕遇地震下保持基本一致的性态控制水准．

Thoughts and Cases for Improvement of Seismic Fortification Measures of Reinforced Concrete Structures in China

The relationships between relative levels of design seismic actions in different fortification zones and related seismic fortification measures in Chinese codes are different from those in foreign codes. In order to eliminate the possible unfavorable effects of this difference on earthquake-resistance of structures and keep the same seismic performance among structures in different fortification zones, with case studies of reinforced concrete frame structures of Earthquake-Resistant Grade Ⅱ in zones of Earthquake Intensity 8 （0.30g） , a series of inelastic dynamic analyses with multi-wave inputs under major earthquake were made. The seismic response performance of structures under strong ground motions were contrastively analyzed. The improvement scheme of ductility seismic fortification measures in Chinese codes was explored preliminarily. The results indicate that consistent seismic performance level of structures under major earthquake in different seismic fortification zones could be obtained by enhancing the ＂strong column and weak beam＂ measures and other detailings of seismic design, while keeping the relative levels of design seismic actions unchanged.