| Prestressed space steel structure is a kind of new structural style which is produced from the combination of prestressed technology and space structure system. It was proved to be of good property of load carrying capacity. Suspend dome structure (SDS) is a new type of prestressed space steel structured style which has developed since the late 20 years.With the prestress acting on lower chord, the internal force and displacement produced of the upper reticulated shell is of opposite direction of loading, which strengthen the overall stability of structure.As the shortage of practical projects and the lack of construction experience of SDS, especially for chamfering triangle SDS, it is necessary to do analysis of construction process and prestress optimization. In the dissertation, the characteristics of SDS and the achievement which has been got around the world are summarized. In addition, the non-linear finite-element analysis theory and solution method which are used in the construction process of SDS are also introduced. Taking the Konggang gymnasium project as an example, theoretical analysis focusing the construction process and prestress optimization of large-span chamfering triangle SDS is carried out.The construction process analysis of SDS consists of shape-finding analysis and prestress-tension analysis. On basis of non-linear finite-element principle, differentiating the initial state, geometrically zero state and loading state for SDS, it is shown that the construction process is the change from geometrically zero state to initial state and this process is analyzed by finite element method for chamfering triangle SDS. Using the method of tensile relaxation the analysis of structural forming process.The member internal forces, joint displacement and the prestress variation of chamfering triangle SDS among different cables is obtained with the increase of cable forces in the construction process.Based on the static analysis of foure prestress methods for the same chamfering triangle SDS, the member internal forces, joint displacement and the support horizontally radial dispalcement of the foure methods are compared. In addition, the compositive prestress optimization, which could increase the load-capability dramatically, is proposed. |
