大跨平坡屋盖风荷载折减的移动平均法
Wind loading reduction on large-span flat roofs using moving average method

根据大跨平坡屋盖脉动风压相干函数导出气动导纳函数，将气动导纳函数与滑动平均滤波器按照截止频率相等的原则进行等效匹配，推导出适用于大跨平坡屋盖风荷载折减的移动平均法。基于某博物馆大跨平坡屋盖风洞测压试验，对本文提出的风荷载折减方法合理性进行验证。研究结果表明：基于风洞试验的统计方法比规范方法在计算大跨平坡屋盖最不利设计风荷载方面更合理；而随着平坡屋盖结构尺寸的增大，最不利设计风荷载折减程度趋于稳定；本文提出的风荷载折减方法，能为大跨平坡屋盖结构最不利设计风荷载的合理确定提供参考。
Based on the expression of the coherence function of fluctuating wind pressure on the large-span flat roof, the aerodynamic admittance function was first presented. Then the moving average method for wind loading reduction on large-span flat roofs was provided after matching the cut-off frequency of the aerodynamic admittance to that of the moving average filter. Finally, the rationality of the present method was verified by using the pressure data on a flat-roof museum building from wind tunnel test. The research shows that, compared to the code method, the statistical method based on wind tunnel test data is more acceptable for calculating the most critical wind pressure on large-span flat roof; while with the increase on roof span, the wind loading reduction of a flat roof under the most critical scenario tends to be stable. The present method can provide a useful way to reasonably determine the most critical wind loading on large-span flat roof structures