The greenhouse will be subjected to various loads during construction and use. The temperature-air structure is a force-bearing system used to withstand various load-cutting effects, and is generally composed of purlins, roof trusses, beams, gutters, and columns. The components of the greenhouse structure are called components. The greenhouse structure design is to choose a reasonable balance between economy and reliability, so that the constructed greenhouse structure can meet various expected functions. Common greenhouses include plastic greenhouses, single-slope solar greenhouses and multi-span warm banquets. There are many types of greenhouse structures, and there are many types of materials used in the structure, including steel structure, bamboo and wood structure and mixed structure, among which steel structure is the most widely used.
According to the design ideas of steel structure, this method summarizes the basic requirements of greenhouse structure design and the functional requirements of greenhouse structure. The purpose of the greenhouse structure design is to ensure that the designed structure is safe, applicable, economical and reasonable, and has sufficient reliability, that is, within the design reference period, under the specified conditions (normal design, normal construction, normal use and normal maintenance) ) The structure can complete the predetermined functions.
Basic regulations and requirements for greenhouse structure design
1. Security. The greenhouse structure can withstand various loads that may occur during normal construction and normal use, and will not exceed the material strength limit or lose the stability of the structure under the load.
2. Applicability. The greenhouse structure has good working performance under normal use load, such as no excessive deformation caused by normal use of color sound.
3. Durability. Under normal use and normal maintenance conditions, the greenhouse structure has sufficient durability within the specified service life, and the service life of the structure will not be affected by factors such as corrosion. Meeting the above three requirements means that the greenhouse structure is reliable. Obviously, the method of improving the safety margin in the design can always meet the requirements of structural reliability, but this will inevitably reduce the economics of the structural design. The reliability and economy of the structure are often contradictory. Therefore, the scientific design requires that the structure is economical and reasonable on the basis of ensuring the reliability of the structure.
The design period of the greenhouse structure should be determined according to the type and purpose of the greenhouse, generally 15 years, 10 years or 5 years. The minimum design service life of the glass greenhouse should not be less than 15 years. For greenhouses with precious crops or expensive indoor equipment, it is recommended that the minimum design service life is not less than 10 years.
