The overturning resistant performance of base-isolated structures subjected to near-fault earth quake was analyzed. The formula of the ratio of anti-over turning moment to overturning moment was established first and then five records of near-fault pulse-like ground motion and far-field earthquake were chosen, respectively, to set up the analysis model of framed anti-vibration structure. The influence of the earthquake intensity and the pulse effect of near-fault ground motion action on the overturning resistant performance of base-isolated structure was analyzed. The numerical computation result showed that base-isolated structure would exhibit worse overturning resistant performance with larger seismic peak acceleration. The ratio of anti-overturning moment to overturning moment decreased by more than 40% under rare earthquake of scale 7 when compared to that of scale 9. The pulse effect of near-fault ground motion action on overturning resistant performance of base-isolated structure was worse compared with far-field earthquake. Much more disciplinary action must be taken against the overturning resistant property of base isolated buildings during the design in near-fault area.%分析基础隔震结构在近断层脉冲型地震作用下的抗倾覆性能.首先建立隔震结构抗倾覆比的计算公式;然后选取近断层脉冲型地震动和远场非脉冲型地震动记录各5条,建立框架隔震结构分析模型,分析地震烈度及近断层地震动脉冲效应对基础隔震结构抗倾覆性能的影响.数值计算结果表明,地震动加速度峰值越大,基础隔震结构的抗倾覆性能越差,9度罕遇地震时的隔震结构抗倾覆比值较7度罕遇地震下减小40％以上;与远场非脉冲型地震相比,近断层脉冲型地震动对基础隔震结构抗倾覆性能的影响更为不利;近断层地区隔震结构设计时对抗倾覆性能应该采取更为严格的标准.
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