Research On Load Of Greenhouse Structure Induced By Wind Force

It is the keys of the building and structural design theory of structures to resist the wind , the domestic and international scholar has loaded and done a large amount of research to the structural wind. The greenhouse, as a kind of structures, its structure is the same as other buildings, need to meet certain stability and reliability requirement. So, the structural design must consider the wind pressure. With industrialization in the facilities of agriculture, the structural stability of greenhouse is directly related to the benefit and returns. But at this stage, different conditions greenhouse design, the designers who have no strict distinction between the wind pressure coefficients of different conditions make the wind-resistant design in a single greenhouse conditions; the other hand there is no other working conditions for reference corresponding to the wind pressure coefficients. This has raised the unpredictable factors for application of the latter part of a greenhouse.Around the greenhouse has the more complex on flow wind field, its superficial wind pressure distribution is the basis of the design and the optimized that greenhouse goes against the wind. In order to textually research the difference wind pressure on the greenhouse different operating mode, understand the distributed situation of its superficial wind pressure, and simultaneously provide the reference for the next greenhouse design, there has especially established three dimensional physical model of greenhouse under two kind of operating modes-being visor curtain or no, and has carried on the wind tunnel test in JiangSu University. The testing was based on the stable state and incompressible air stream,.The test result indicated, for the greenhouse to be visor curtain, the periphery wind field became exceptionally complex. Under two kind of operating modes, wind pressure coefficient has the very big difference in the identical position of greenhouse surface. When non-visor curtain, the wind pressure coefficient of greenhouse surface is a curve fitted, or don't change with wind speed; After changing wind angle, the wind pressure coefficient has slightly reduced. When being the visor curtain, under the identical wind angle, the wind pressure coefficient was quite different because of the wind speed influence, and in the same situation, the wind pressure coefficient must be bigger than the wind pressure coefficient of non-visor curtain. Thus, in the design process of greenhouse that has visor curtain , the traditional wind pressure coefficient is not able to guarantee the safety and stability of greenhouse.The author who used commercial software Fluent (hydrodynamics software) carried on the simulation test of mechanics performance of greenhouse structure system. Value simulation was based on steady flow of greenhouse surrounding air. Through the standard k-εrapids model, and the wall surface function in the near wall place, carried on the simulation to the outside surface pressure distribution of greenhouse.Analysis of greenhouse design has been the focus of attention; the authors use the finite element (FEA) knowledge, right DY-82641 single greenhouses for structural analysis.Finally, the author has also carried on some elaboration about the reliability analysis of greenhouse.