| In recent years, with the development of traffic technology, then the development of variety of bridge-type is also produced, long-span suspension bridge with long span cable-stayed bridge is developing rapidly. But, because space for the construction of a bridge, construction conditions and the economic cost are restricted, these long-span bridge types have increasingly constrained; bridge-type diversification and the increase in space-bridge structure are the trend of the bridge development. With new technology, new materials and the emergence of high-performance computer, making the theory of bridge design to become the rapid development and improvement in the last three decades.Aspects of bridge conceptual design: through development of the analytical and numerical analysis theory, defining mechanical properties of the typical structural system, a variety of style of suspension bridge, cable-stayed bridge and cooperative system is the emergence. Self-anchored and ground-anchored suspension bridges are liked by everyone with its graceful linear, the appearance of novel and flexible bridge site. The ground-anchored suspension bridge is the first choice for long-span and super-long-span bridge design, but, is more and more worried by people because of its construction of huge anchorage, and economic constraints. Because self-anchored suspension bridge is more and more liked by people, a large number of large-span self-anchored suspension bridges also came into being. However, because of constraints of materials and mechanical systems, long-span self-anchored suspension bridge has been greatly restricted, self-anchored bridge is only the small and medium-span bridge. The long-span cable-stayed bridges are also more and more built. Cable-stayed bridge of more than 1000 meters span has become in the world, trends of development is a sharp increase. Cable-stayed bridge is liked by people because of its stiffness and strength of tall and straight, is be able to made everywhere in the small and medium span, long-span bridges, crossing river, across the sea, the complex geographic terrain, as well as wind and seismic harsh environmental conditions of the terrain. However, the increase with cable-stayed bridge span, requirements with the mechanical system, cable-stayed bridge tower more and more is higher, height of the tower of cable-stayed bridge more than 1000 meters span has reached more than 350m or 400m, such a high general building is challenged by mechanical and environmental, the bridge is more affected because of static and dynamic continuing imposing, construction of difficulty and monitoring of quite complex. Moreover, it is restricted inevitably by terrain, as well as air traffic control and the external things etc. Taking consideration of the above many factors, based on examples of Dalian Bay Bridge, Dalian University of Technology Task Force presented a self-anchored cable-stayed-suspension collaboration system bridge project to solve the corresponding problems, but also affected by development funding issues by western transportation construction projects " Cable-stayed-suspension bridge research cooperative system " of the Ministry of Communications in China. Western Transportation Construction Science and Technology Project Fund Number (200,631,882,350).Self-anchored cable-stayed-suspension bridge of a new type of bridge structure has now been adopted by the engineering sector, because of many advantages of the traditional cable-stayed-suspension bridge, and a strong competitive edge due to the cancellation of a large anchorage, better adapting to the construction of deep-sea and soft soil in the bad conditions of geological environment, however, the existing literature of view, the research for this bridge-type static and dynamic properties is quite rare. The paper has carried out several research on large-span self-anchored cable-stayed- suspension bridge on the overall stability, ultimate bearing capacity, structural dynamic characteristics of seismic response analysis, seismic vibration, flutter stability, seismic reliability degrees, the structural system reliability etc, In order to ensuring self-anchored cable-stayed-suspension bridge construction, and the safety during the operation, making self-anchored cable-stayed-suspension bridge structural design more economical and reasonable, based on geometric nonlinear finite element theory, graph theory, optimization theory, with background of Dalian Bay Bridge and Jinzhou Bay Bridge engineering. Work and major achievements of this paper are:(1) Based on the basic design data and requirements, the designs on the new type of structural system of Dalian bay Bridge are proposed. A lot of creationary achievements will be acquired on Dalian Bridge, called the single tower self-anchored suspension bridge.(2) This paper applied graph theory to thin-walled structure calculation, and established a thin-walled cross-section of the graph model, described succinctly and accurately the topolog -ical relations of thin-walled cross-section in correlation matrix and the basic loop matrix. And derived coordinates of fan features, matrix equation of bredt shear flow,secondary shear flow and the bending shear flow in graph theory. Studied calculations of the thin-walled cross-section limit torque in the free torsion in graph theory.(3) Carried out analysis of the relevant theory of the suspension bridge, cable-stayed bridge, self-anchored cable-stayed suspension bridge. This paper make use of large-scale general finite element program ANSYS, included in the above-mentioned non-linear factors in the solution process, with Dalian Main Navigation bridge Dalian Port for the engineering background, establishing plane frame calculation model. Carry out self-anchored suspension bridge mechanical analysis in beam-column effect theory and theory of virtual displacement principle, better analyzed this non-linear mechanical effects generated by the bridge with ANSYS finite element software.(4) Based on finite element theory, considering a variety of non-linear factors, establishing the finite element model, carried out a detailed static behavior analysis to self-anchored cable-stayed-suspension bridge of Dalian Bay Bridge of main span of 800m, including stiffness, internal forces, sling fatigue, deformation of transfer zone.(5) Dynamic characteristics of self-anchored cable-stayed suspension bridge mainly include natural vibration frequencies and principal modes, which are the base and precondition of dynamic response analysis for the kind of the system bridge. Dynamic characteristics of Dalian bay bridge, belonging to self-anchored cable-stayed suspension system, are analyzed and compared with those of earth-anchored cable-stayed suspension bridge with the same span and structure parameters by using spatial finite element model, some new traits of dynamic characteristics for the system bridge are summarized and the reasons are discovered.(6) By applying highly efficient pseudo excitation method, the dissertation analyzes random seismic response of self-anchored cable-stayed suspension bridge under P wave, SH wave and SV wave excitation and the influences on the peak values of internal forces and displacements of some factors such as multiple-support excitation and seismic spatial effect and varieties of damping ratio are considered. Subjected to multiple-support uniform and non-uniform excitation, the traits and regulations of seismic response for Dalian bay bridge are compared on basis of the equivalent power spectrum density function made by criterion response spectrum, conclusions drawn provide some valuable references for the anti-seismic design of the new type of bridge. In view of the damping as the structural dynamic properties and an important parameter of dynamic response, this chapter examined how to choose the damper, and choosing mainly viscous dampers, introduced a viscous damper to principle and application methods, study the impact of the structural seismic response because of the changes of damping ratio, providing a valuable reference for the further design of the new bridge system.(7) Carried out Flutter stability analysis of potential wind-induced vibrations of large-span self-anchored cable-stayed-suspension bridge in Dalian Port Bay.This paper briefly describes the bridge's basic theory of the bridge static wind effects and wind-induced vibration, carried out the research with wind resistance through the theoretical analysis to large-span self-anchored suspension bridge, based on the engineering background of Dalian Bay Bridge. Major research:①Carried out flutter stability of self-anchored cable-stayed-suspension bridge of a main span 800m, in multi-mode flutter finite element method, in the main cable long-height ratio, hanging cross-ratio, surface layout of cable surface of cable-stayed bridge, the settings of side cross-supporting bridge piers, and design parameters such as main beam constitution etc. carried out key design parameters affecting the bridge, and discuss rational structure of self-anchored cable-stayed-suspension in the perspective of the wind resistance performance.②The impact resulting flutter can not be ignored in the structural dynamic properties and the effects of non-linear changes of air forces caused by deformation for long-span self-anchored cable-stayed-suspension bridge. Established computing program of flutter analysis of three-dimensional non-linear method for self-anchored cable-stayed-suspension bridge, Based on the structure of deformed state and giving full consideration to non-linear effect of structural deformation. Carried out analysis and research of flutter reliability on self-anchored cable-stayed-suspension in Dalian bay, revealed the extent and mechanism of flutter reliability effect of non-linear effect resulted from structural deformation on long-span self-anchored cable-stayed suspension bridge.(8) The pseudo excitation method is introduced in the structural dynamic reliability analysis, which overcomes the shortcoming of time consuming of the random vibration approach and makes it possible to apply the random vibration approach for large and complex bridge structures. In the paper, the reliability of important structural component, piers and towers used as resist the seismic action, is analysed in detail. It is special considered that the space effect, non-stationary and damping ratio can impact on the dynamic reliability.(9) The system reliability method is established for the self-anchored suspension bridges under ultimate limit states. The globalβ-unzipping method and the different equivalent recursion algorithm are adopted to recognize the significant failure models and equivalent limit state functions. The results show that the globalβ-unzipping method is highly efficient and accurate in recognizing the main failure models of structural system. The bond of failure probability of the self-anchored suspension bridge system is calculated by the Ditlevsen's theory.
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