内爆炸下扁平大空间中柱表面荷载的确定

Determination of Surface Blast Loading of Middle Column in a Flat Large Space under Internal Explosion

为研究地下停车场等扁平大空间内发生爆炸时中间柱所受到的爆炸荷载,采用AUTODYN软件分析了比例距离、截面尺寸和柱高对中柱迎、背爆面爆炸荷载的影响情况。爆炸荷载采用中柱迎爆面底部中心反射超压峰值和反射比冲量,以及迎、背爆面任意高度处归一化反射超压峰值和归一化反射比冲量来表征。研究表明,截面宽度对柱迎爆面底部中心反射超压峰值和反射比冲量有较大影响,该影响随比例距离的增加而减小,柱高对其几乎没影响;截面宽度和柱高对中柱迎、背爆面归一化反射超压峰值和归一化反射比冲量的影响很小;比例距离对迎爆面归一化反射超压的影响在柱身相对高度大于0.8处较大,对背爆面归一化反射超压峰值和迎、背爆面归一化反射比冲量影响较小。最后,给出并验证了内爆炸下扁平大空间中柱爆炸荷载表征量的计算公式。

In order to study the blast load on the middle column when the explosion occurred in the flat large space structure such as underground parking lot,AUTODYN software was used to analyze the influence of scaled distance,section size and column height on the blast load on the front and back of the middle column.The blast load is characterized by the reflected overpressure peak and the reflected specific impulse at the bottom center of the front,as well as the normalized reflected overpressure peak and the normalized reflected specific impulse at any height of the front and back.The research shows that the section width has a great influence on the reflected overpressure peak value and the reflected specific impulse at the center of the bottom of the front of the column,which decreases with the increase of the scaled distance,and the column height has little influence on it.The section width and column height have little influence on the normalized reflected overpressure peak and normalized reflected specific impulse of the front and back of the middle column.The influence of scaled distance on the normalized reflected overpressure of the front is greater when the relative column height is greater than 0.8,and the influence on the normalized reflected overpressure peak of the back and the normalized reflected specific impulse of the front and back is smaller.Finally,the calculation formula of the characteristic parameters of the blast load of middle column in a flat large space under internal explosion is given and verified.