Authors

Abstract

Plastic greenhouses, due to their lightweight structural characteristics, often exhibit limited resistance to strong winds. To improve their wind-resistant performance, this study applied a combined approach using finite element modeling and excitation testing. Dynamic response data of the greenhouse frame were collected through excitation experiments, and frequency-amplitude characteristics were obtained using fast Fourier transform (FFT). Modal analysis of the finite element model was then performed to verify the experimental results, and the structural damping ratio was subsequently calculated. The results show that the acceleration amplitudes at the excitation point in the x- and z-directions were 1.66 and 1.25 times higher than those measured at adjacent frame sections, respectively. The natural frequency of the greenhouse frame was determined to be 3.15 Hz, and the corresponding damping ratio was 0.018. These findings provide insight into the dynamic behavior of flat-elliptical pipe greenhouse structures and offer a methodological reference for future structural optimization and the development of relevant engineering design standards.

Abstract in Chinese

塑料大棚由于其轻量化设计，在面对强风时的抵抗能力有限。为了提高其抗风性能，本文采用有限元法（FEM）和激振试验相结合的研究方法。通过激振试验获取大棚骨架的动态响应数据，利用快速傅里叶变换（FFT）提取幅频特性曲线，通过对骨架有限元模型进行模态分析，验证试验结果，最终计算得到结构的阻尼比。研究结果表明：激振骨架x，z向加速度幅值波动范围分别为相邻骨架的1.66倍和1.25倍，此类大棚骨架的自振频率为3.15Hz，阻尼比为0.018。这些结果有助于更深入地了解大棚骨架的结构动力学，并为未来的结构优化和设计标准制定提供方法论见解。