| Cable is widely used in the actual project of prestressed steel structure for its mechanical properties can be fully used. As flexible and innovative architectural form and efficient structural performance, Cable supported structure systems are widely studied and applied. However, there is little systematic study on the linear thermal expansion coefficient of cables and the mechanical performance of cable supported structure at present. As the main foundation of "performance-based design" theory of cable supported structure, the reliability is the main elements to be considered in future design. This dissertation does a systematic study on the characteristic of cables, mechanical properties and reliability of cable supported structure systems.This thesis discussed several issues about the cable characteristics, also analyzed systematically on the cable tension method of different cable supported structures. Considering the effective factors of the variations from material performance and other patterns, the statistical parameters of the resistance of cables are carried out based on test results. By different safety class, the reliability index, optimum resistance partial factor and design strength value of cables are determined through the reliability analysis which considering adjustment coefficient of resistance, and they may serve as a reference for the amendment of structural design codes.The Monte Carlo method, Response Surface method and APDL language are applied to write a corresponding program, thereby carrying out reliability calculation; the reliability and parameters sensitivity of the beam string structure under both safety and applicability conditions are provided. The reliability influence coefficients of structural components are given through computing the decrease of structure system reliability caused by the component stiffness decrease. Then the weight coefficient equation is deduced by linear weighted method, thus a computational model of key components is determined. A practical example of beam string structure is given for the purpose of illustrating the strategy.With the Monte Carlo method which based on the response surface function, the stability of cable supported barrel vault and its reliability in integral buckling failure mode are researched. Moreover, the influence of the rise-span ratio on the reliable performance in strength and displacement failure modes are discussed, as well as sag-span ratio, number of struts and prestressing. The optimal values of the rise-span ratio, sag-span ratio and number of struts are given. At last, the target reliability controlled by applicability is obtained. They may serve as references for the analysis and design of this kind of structure.The temperature is an important factor which affects the force status of the cable supported structure. The method of compensating for the prestress losses under temperature action is derived. The reliable performance research of cable supported structure considering temperature impact is carried out, the variation of reliability with temperature and different cables are analyzed. The results indicate that the temperature has impact on the reliability of structure applicability, the reliability index maybe not meet require of the standard, but it is make good the structure after compensating prestress with the method .There has been no accurate research on the linear thermal expansion coefficient of cable. Therefore the test equation is provided and the test principle is determined, two of expansion coefficients measuring instruments respectively based on air medium and water medium are manufactured. In which, four types of cables as steel wire rope cable, steel strand cable, steel tendon cable, and steel rod are chosen to test their coefficients of linear thermal expansion. According to the coefficient of linear thermal expansion of cables have been measured, the mechanical properties of cable supported structure are analyzed in regard to temperature action. And finally, based on test model of cable supported barrel vault, the mechanical performance test of cable supported barrel vault under the temperature action is carried out. The variations with temperature of internal forces of cable and chord rod are given. The results show that, it need to consider the temperature effect on the mechanical properties of cable supported structure in analysis and design. The results also proved that the linear thermal expansion coefficient of cable suggested by this thesis is feasible.
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