Abstract
Greenhouses had to be designed to sustain permanent maintenance and crop loads as well as the site-specific climatic conditions, with wind being the most damaging. However, both the structure and foundation are regularly empirically calculated, which could lead to structural inadequacies or cost ineffectiveness. Thus, in this paper, the structural assessment of a multi-tunnel greenhouse was carried out. Firstly, wind loads were assessed through computational fluid dynamics (CFD). Then, the buckling failure mode when either the European Standard (EN) or the CFD wind loads were contemplated was assessed by a finite element method (FEM). Conversely to the EN 13031-1, CFD wind loads generated a suction in the 0–55° region of the first tunnel and a 60% reduction of the external pressure coefficients in the third tunnel was not detected. Moreover, the first-order buckling eigenvalues were reduced (32–57%), which resulted in the need for a different calculation method (i.e., elastoplastic analysis), and global buckling modes similar to local buckling shape were detected. Finally, the foundation was studied by the FEM and a matrix method based on the Wrinkler model. The stresses and deformations arising from the proposed matrix method were conservative compared to those obtained by the FEM.
Highlights
Greenhouses extend all over Europe (Figure 1), the number of these structures are especially predominant in some regions due to the favorable local meteorological circumstances (e.g., Mediterranean climate characterized by warm and humid winters, hot and dry summers and clear days with fairly high radiation even during fall and winter) in which crop production in greenhouses is a rising agricultural sector.Among European nations (Figure 1), Spain is the country with the highest greenhouse area and accounts for the 35% of the total reported statistics on protected cultivation for the latest available dataset (i.e., 2016) provided by Eurostat [1]
No limitations in the depth of the greenhouse were contemplated, as the external loads applied to the structure are constant for all central portal frames regardless of the total length
The findings reported by Kim et al [44], who observed a good correlation between the results arising from a computational fluid dynamics (CFD) numerical simulation and a wind tunnel experiment, are used as basis for the CFD
Summary
Greenhouses extend all over Europe (Figure 1), the number of these structures are especially predominant in some regions due to the favorable local meteorological circumstances (e.g., Mediterranean climate characterized by warm and humid winters, hot and dry summers and clear days with fairly high radiation even during fall and winter) in which crop production in greenhouses is a rising agricultural sector. The mostgreenhouses popular Spanish greenhouse was the flat parral-type, which originated from Almeria and is characterized by an almost non-existent slope. Due to the increase in the level of automation, the most popular Spanish was the flat parral-type, originated frominAlmeria and characterized by angreenhouse almost non-existent slope. Due to the increase the level automation, the multi-span or multi-tunnel greenhouse (as could be observed in Figure 4) is the mostof greenhouse structure employed to date [24]. (as could be observed in Figure 4) is the most automation, the multi-span or multi-tunnel widely greenhouse structure employed to date [24]. Ha et al [39] reported that greenhouses foundations are regularly empirically calculated regardless of the specific soil mechanics This approach could either lead to structural inadequacies or cost ineffectiveness. The paper addressed the influence of the wind load consideration on the structural behavior, as well as the foundation through the development of a three-dimensional (3D) matrix calculation method based on the Winkler model to design the cylindrical footings
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
