Force Analysis And Optimizational Design Of Structure Of Big-bay Multi-span Greenhouse

Large and modern multi-span greenhouse plays a very important role in developing facility agriculture and achieving factory farming production in China.However,the high cost of structure of multi-span greenh-ouse stops it from developing in China.In view of imperfection of design codes and theory about greenhou-se structure in our country,on the basis of analysising the development situation of multi-span greenhouse in China and reviewing the research situation of greenhouse structure at home and abroad, LWPRR1Z-12-7.05 type multi-span greenhouse was researched in this paper.The research's contents as follows:(1) In order to adapt to new development requirements of agricultural parks,LWPRR1Z-12-7.05 was a new form of structure based on Venlo multi-span greenhouse by increasing the span and the height of colu-mn,besides,truss in direction of bay was used as beam support, All the changes made the structure more tal-1 and spcious interior space layout more flexible, which made up for the inadequacy of Venlo type.(2) By consulting revelant design codes about greenhouse structure,loads and load combinations on the structure were analysised.Then,through the finite element analysis software ANSYS plantform,the two-demensioned modeling work of the bent frame structure of greenhouse was done in it.By the simulated stre-ss analysis of structural model under the three main load combinations,the structure diagram,displacement and deformation diagram in the corresponding cases were obtained.(3)Optimizational design of the structural model was done through the ANSYS where the sectional siz-e of structural components was used as design variables and the total steel weight of the structure was used as the objective function.As result,the total steel weight reduced by 10.7% after optimization under the guar-antee of security and stability of greenhouse structure,and the mount of steel was reduced 1.5 kilograms pe ersquare meter area.In this paper,this type of multi-span greenhouse structure was analysised and optimizated by ANSYS. At last,a more economic and reasonable structure for reference which was more promoted easily was designed.