中文摘要：

从震害统计和数值模拟两个方面研究了按现行抗震规范设计的钢筋混凝土框架结构的抗倒塌能力。汶川地震大量钢筋混凝土框架结构震害统计表明，按7度抗震设防的结构在地震烈度达到9度或加速度峰值达到400gal，开始出现倒塌破坏（占1％～2％）；当地震烈度达到11度或加速度峰值达到800gal以上时，出现大量的倒塌破坏（占60％以上）。进一步以汶川强震记录为输入，对两个典型的钢筋混凝土框架结构进行了增量动力分析。结果表明：7度抗震设防时可抵御300ga卜500gal加速度峰值作用（地震烈度近似9度）；按8度抗震设防时可抵御400gal～600gal加速度峰值作用（地震烈度近似10度）。总体上看按现行抗震规范设计的钢筋混凝土框架的超强系数基本大于2。

英文摘要：

By seismic hazard investigation and numerical simulation, the collapse resistant capability of a reinforced concrete frame structure designed according to active seismic design code is studied. The seismic damage statistics indicate that RC frame structures designed to comply with seismic fortification intensity of 7 commence to collapse （account for 1%~2%） when earthquake intensity reach to 9 or peak ground acceleration （PGA） exceeds 400 gal. Large numbers of RC frame structures （over 60%） will collapse when the earthquake intensity reach to 11 or PGA greater than 800 gal. The further incremental dynamic analysis under Wenchuan earthquake waves shows that frame structure designed according to seismic intensity 7 can overcome PGA from 300gal to 500gal （approach to seismic intensity 9） without collapse, and it can overcome PGA from 400gal to 600gal （nearly seismic intensity 10） while designed according to seismic intensity of 8. As a result, it is found that the overstrength coefficient of a RC frame structure strictly conform to the current seismic code is larger than 2 usually.