Research On Static Properties And Stability Of 800 Meters Super-large Span Suspension Mega-latticed Structure

With the development of the society and the progress of science and technology,the span of buildings is increasing,and structural engineers start to challenge the super-long-span structure.At the same time,the demand for super-long-span structures in human society has become increasingly prominent: the establishment of residential areas in harsh conditions,the protection of cities from environmental threats,energy saving and emission reduction considerations.Due to the increase in the span of structure,there are many difficulties in the application of the traditional structure,so it is necessary to find a suitable structure form for super-long-span structure.The span of bridge structure has successfully exceeded 1000 meter,so applying structure form of bridge to super-long-span structure has a solid theoretical basis.The purpose of this dissertation is to investigate property and applicability of suspension hybrid structure with 800 m span,formed by principles of suspension bridge.The control parameters of the geometrical shape of the structure are based on geometric topological relationship with ANSYS program,and the structural model is established.The initial form analysis,stability analysis,parameter analysis and anti-progressive collapse analysis of the suspension cable were carried out.This work analyzes the mechanical performance of the super-long-span structure and provides guidance for the following theoretical research.The conclusions are included in the following aspects:1.The APDL parametric language is used to make the program of the model,and member selection,morphological analysis and load reanalysis are carried out to obtain satisfactory results.The static response of the structure under 12 loading cases is calculated,and the response of the structure is summarized.The sensitive case of the structure is obtained.2.The load-displacement curve of the structure is calculated by the nonlinear analysis method to study the stability of the structure.The arc-length method is used to trace the equilibrium path.The results show that there is no descending section in the whole process curve.After the structure displacement reaches a new equilibrium path,the displacement shape changes,but the load is still rising,so the structure does not have the instability problem and the stiffness becomes the main consideration.3.The influence of geometric parameters on the mechanical properties of the structure was studied.Seven parameters of geometric shape control are analyzed in 77 cases.The relationship between mechanical properties and geometrical parameters is summarized,and reasonable ranges of values for each parameter are summarized.4.It was examined whether the rupture of one hanger would lead to continuous ruptures of the other hangers,causing a progressive collapse of the structure.Transient dynamic analysis method is adopted to simulate the process of fracture.The time-history curves for displacement of the structure,the stress of main cable and the tension of adjacent hanger after the rupture of hangers are analyzed,and the peak of dynamic response and the structural response in new equilibrium state are discussed.The evaluations of the hanger fracture are implemented.