Stability Analysis Of Cable-stayed Bridge With Steel Arch Pylons

Cable-stayed bridge with steel arch pylons has special structure and beautiful shape. Its space and force performance are different from that of conventional cable-stayed bridge. But as a new cable-stayed bridge architecture, there are less research on the stability studies of the various stages. In this thesis, based on the Xi’an cable-stayed bridge with steel arch pylons, builds the finite element model of stability analysis, provides technical support for large-scale application of such follow-stayed bridge system. The main work is as follows.(1) Describes the two kinds of stability theory and the basic theory of finite element analysis method; Combined with the stability criteria and methods of the current bridge, and based on the existing bridge stability criteria, the calculation and analysis of the reference standard is established in this paper; Through the research on the theory and method of structural stability analysis, provides a theoretical basis for the study of the stability of cable-stayed bridge with steel arch pylons.(2) Stability analysis of the lateral wind load and live load to study the buckling mode and stability coefficient change trend of cable-stayed bridge with steel arch pylons.The results show that ateral wind load and live load on the structure of the first kind of stability influence is larger as the first order buckling mode is floating beam first longitudinal, and the effect is more obvious with the buckling mode number increasing.(3) Stability analysis of the five typical construction stage such as bare tower stage,frame beam stage, the first stage of the suspension cable stage, the end stage of the suspension cable and the two stage dead load stage.It was found that the stability coefficient decreases obviously during the frame beam stage and both the lateral wind load and the setting of the temporary pier have great influence on the elastic stability of the structure.(4) This paper change the five parameter such as initial cable tension, constant load, sections of cables, cable stiffness and beam stiffness to analyze the sensitivity of stability.It was found that the cable force value, dead load, cable section,cable stiffness and beam stiffness of steel arch tower cable-stayed bridge have significantly affection on stability. The sectional area of cable, cable stiffness, longitudinal stiffness are three positive correlations and cable force value,structure dead load are two negative correlations.The outcome of this thesis provides theoretical basis and reference for the stability analysis of cable-stayed bridge with steel arch pylons. To a certain extent, it can guide the design and construction process. The outcome of this thesis has great importance of practical value for the application and development of cable-stayed bridge with steel arch pylons.