矩形张拉膜结构预张力的试验研究

Experimental Study on Pretension of Rectangular Tensioned Membrane Structure

采用双轴张拉支架施加薄膜预张力,利用数显式推拉力计测量张力变化,对膜面施加集中冲击荷载,采用非接触式激光位移传感器测得膜面各特征点的位移变化。对比薄膜在不同预张力作用下的振幅、速度、加速度。试验结果表明,薄膜振动的振幅随着预张力的增大而逐渐减小,振幅衰减的速度和加速度随着预张力的增大而增大;但是当预张力增大到一定程度以后,这种变化规律的趋势逐渐减弱,趋于稳定;通过试验得到了该预张力的范围。

The pretension of membrane is applied with biaxial tension bracket. The digital indicators for push-pull force is adopted for measuring the tension change. Non-contact laser displacement sensor is applied to get the displacement change of the features of rectangular membrane surface. The amplitude, velocity and acceleration of the membrane under different tensions are compared. The study results show that the vibration amplitude of rectangular membrane decreases as the pretension increases, the declining rate and acceleration of the amplitude increase with the enhancement of the pretension, but the change law steadily weakens and is stabilized when the pretension increases to a certain extent. The scope of the pretension is confirmed by the study.