气屏柔性雨幕墙的压力平衡及气屏柔度的影响

Pressure Equilibrium of Rainscreen with a Flexible Air-barrier and the Effect of Air-barrier Flexibility

根据是否采用空腔容积变化量相对于初始容积为小量的假定,以及气屏运动方程是采用动态方式还是准静态方式,给出了气屏柔性雨幕墙压力传递的四种不同算法,并详细分析了具有常规尺寸及气屏刚度的气屏柔性雨幕墙在设计风压作用下的雨幕两侧压差,对比四种算法的结果,发现:空腔容积变化量相对于初始体积为小量的假定是成立的,气屏运动方程采用准静态方式是可行的。另外,利用四种算法考察了气屏刚度对雨幕墙压力平衡的影响,发现:对于由外压到雨幕两侧压差的传递函数幅值谱,其受气屏刚度的影响方向随着频率的不同而有所不同,在低频段,压差传递函数幅值随气屏刚度的增大而减小;在高频段,会出现与低频段不同的规律。

According to whether the change of the cavity＇s volume can be neglected, and the control equation for the air-barrier＇s movement adopts dynamic mode or quasi-static mode, four calculation methods for the pressure transfer of the rainscreen with a flexible air-barrier were introduced. Based on the calculations of this type of rainscreen with normal geometry and the air-barrier＇s stiffness under the ordinary wind load, the results from those four methods were compared. It was found that the change of the cavity＇s volume can be neglected and the control equation for the air-barrier can adopt quasi-static mode. Moreover, the effects of the air-barrier＇s stiffness on the rainscreen＇s pressure equilibrium were examined with those four calculation methods. For the transfer function＇s amplitude spectrums of the pressure drop across the rainscreen, the impact direction by the air-barrier＇s stiffness is varying along the axis of the frequency. For the low frequency range, the bigger the air-barrier＇s stiffness, the smaller the transfer function＇s amplitude of the pressure drop. For the high frequency range, it can be different.