Study On Structure Selection Of The Steel Roof In University Gymnasium

According to the requirement of the newly issued“Building Area Index of General Institutions of Higher Education Building Standard 191-2018”,when the number of students in ordinary colleges and universities is more than 20000,it is necessary to build a medium-sized gymnasium with 4000 fixed seats(excluding movable seats).Therefore,taking this as the background,this dissertation carried out the research on the structural system selection of long-span steel roof according to the construction needs of 4000 medium-sized gymnasiums in ordinary colleges and universities in China.First of all,this paper summarized and classified all kinds of long-span spatial steel structure system which are widely used in the construction of gymnasiums at home and abroad.The main structural features,development and application,advantages and disadvantages of typical long-span structural systems such as space frame structure,truss structure,cable-membrane structure,beam string structure,suspend-dome structure,arch structure and retractable roof structure are introduced in detail.The application prospects of the above long-span structural systems in 4000medium-sized gymnasiums are discussed.Next,this dissertation focuses on the structural selection and structural optimization of the suspend-dome structure system.Taking a medium-sized gymnasium with a diameter of 92m as an example,the Lamella-Kiewitt single-layer reticulated shell suspend-dome is selected as the roof structure,and the finite element modeling analysis is carried out by using the finite element software Midas Gen.The static performance of the structure is obtained by nonlinear geometric static analysis,the eigenvalue analysis is carried out by subspace iteration method,and the response spectrum analysis of structure is carried out.The analysis results show that the Lamella-Kiewitt single-layer reticulated shell suspend-dome structure system adopted in this paper meets the requirements of Chinese design code,and the amount of steel used is less than that of other types of roof structures.Finally,the structural optimization of single-layer reticulated shell suspend-dome structure with the change of main structural parameters is studied,and three main structural parameters,such as rise-to-span ratio,compression strut height and single-layer reticulated shell types,are considered respectively.The finite element comparative analysis of multi-parameter changes is carried out by using the finite element software Midas Gen.The analysis results show that the total steel consumption of the optimized Lamella-Kiewitt single-layer reticulated shell suspend-dome structure with four circumferential ribs is about 45kg/m~2,which has a good economy.The study of this paper can provide a reference for the design of a medium-sized gymnasium in the future.