Abstract
The present paper investigates the collapse process of pipe-framed greenhouses under wind or snow loading based on a non-linear finite element analysis in order to establish more reasonable wind and snow resistant designs. The analytical model is limited to a two dimensional problem. Regarding the wind loading, fluid-structure interaction (FSI) is considered, because the deformation under wind loading may affect the wind pressure distribution significantly. That is, the wind pressure distribution on the deformed structure is computed by Computational Fluid Dynamics(CFD), and then the result is used for the structural analysis at the next step. Focus is on the time-averaged deformation and wind pressure. The results indicate that the FSI effect is fairly small up to the allowable stress or deformation used in the current design standards. However, the FSI affects the collapse load and mode, significantly. Regarding the snow loading, not only even but also uneven distribution of snow accumulation are considered, because wind affects the snow accumulation significantly. The results indicate that the uneven load gives lower collapse load than the even load. It is found that the safety margin up to collapse beyond the allowable stress or deformation is rather small. The analytical results on collapse mode are consistent with the findings of damage investigations both for the wind and snow loadings.
