关于建筑抗震设计最小地震剪力系数的讨论

介绍了GB 50011-2010《建筑抗震设计规范》关于楼层最小地震剪力系数规定的编写背景，及其与其他国家规范的相关规定的区别。论述了结构的最小地震剪力系数（剪重比）与设防烈度、场地特征周期、结构周期、振型、阻尼比等参数的关系。列举了位于不同地区（沿海和内地）、不同高度的超高层建筑设计，说明由于地震作用和风荷载不同，计算的楼层地震剪力系数、层间位移及墙、柱等构件轴压比也会不同。结构对地震作用与风荷载的反应不同，设计应区别对待。只要设计合理，大多数结构的最小地震剪力系数可以满足规范要求。对一幢超高层建筑结构进行全面剖析，综合比较，论证了各类参数之间的关系，证明我国规范关于楼层最小地震剪力系数的规定不但是必要的，也是合理可行的。

Study on the minimum story shear for seismic design of buildings

The regulations and related contents regarding the minimum story shear for the seismic design of buildings issued in ‘Code for seismic design of buildings’ (GB 50011-2010) were briefly described. A comparison between Chinese code and other seismic design codes was carried out. The necessity and applicability of the minimum story shear issued by all these codes were discussed. The calculated base shear of a structure may depend on some parameters, such as the seismic intensity, characteristic period of site, structural periods, modes and damping ratios, etc. The relation among the story shear factor and these parameters were described herein in this paper. The responses to earthquake action and wind load of structures which were of different heights or located in different seismic regions may differ from each other. Some of the key parameters calculated for the seismic design of tall buildings as examples were given to identify that the regulations of the minimum story shear are necessary and implementable for the seismic safety of tall buildings.