纽约世贸中心“油燃致塌说”质疑

Arguments against the version that burning gasoline cause the collapse of New York World Trade Center

从建筑防火的角度对纽约世界贸易中心的坍塌进行了详尽的分析,指出其历火时间并未超过建筑防火规范规定的耐火极限,结构表面的温度也未超过其临界温度,耐火涂料和自动灭火装置等高等级的防火措施均保障了结构的耐火极限,从而说明"燃油烧软钢结构而致塌"的说法缺乏充分的依据.世贸中心坍塌的主要原因是飞机撞击造成塔楼局部破坏,并使楼板超载而逐层塌落,最终导致钢柱失稳而急速垂直坍塌.而燃油起火燃烧使钢柱的承载力下降,加速了这种失稳破坏.

This essay analyses the details of the collapse of New York World Trade Center from the aspect of fire\|prevention. It is pointed out that the lasting burning period did not surpass the ruled fireproof limit, either did not the temperature on the structure face surpass the limited temperature. Some advanced fire\|prevention installations, such as fireproof coating and the automatic fire\|extinguishing system had guaranteed the fire\|prevention limit. So it comes to the conclusion that the version that the softened steel frame caused the collapse has not enough arguments. The main reason is that the ram force of the plane caused a part destroy to the tower and the overload floor slabs collapsed one after another, at last the steel columns lost the stability and it resulted in a rapid vertical collapse. In the same while, the burning of the gasoline decreased the loading ability of the steel columns, which aggravated the damage.