Construction technology structure of multi-span plastic greenhouse
Large multi-span plastic greenhouse is a type of greenhouse that has appeared and developed rapidly in the past ten years. The multi-span plastic greenhouse has the advantages of light weight, less amount of skeleton material, low shading rate of structural parts, low cost and long service life.
1. The overall size of the multi-span plastic greenhouse: This type of greenhouse has different structural dimensions in different countries. But in general, the span of the general greenhouse is 6~12m, the bay is about 4m, and the eaves height is 3~4m. For multi-span greenhouses based on natural ventilation, when the side windows and ridge windows are used in combination, the maximum width of the greenhouse should be limited to less than 50m, preferably about 30m; and for the multi-span greenhouses mainly based on mechanical ventilation, the maximum width of the greenhouse can be Expand to 60m, but it is best to limit it to about 50m; for the length of the greenhouse, from the point of view of ease of operation, it is best to limit it to less than 100m, but there are no strict requirements.
2. The main structure of the greenhouse: The main structure of the multi-span plastic greenhouse is generally made of hot-dip galvanized steel pipe as the main bearing structure, which is factory-produced and installed on site. Due to the light weight of the plastic greenhouse itself and its weak resistance to wind and snow loads, the overall stability of the structure must be fully considered. Generally, vertical diagonal braces should be installed in the second span or the second bay in the greenhouse. The outer protective structure of the greenhouse and the necessary space support should also be considered on the roof. It is best to have diagonal supports (oblique tie rods) anchored to the foundation to form a space stress system.
