The Effect Of Cable’s Corrosion And Relaxation On The Safety Of Prestressed Steel Structures With Inhaul Cables

In recent years, the prestressed steel structure has been widely used for its reasonable force, large stiffness, light weight, good seismic performance, short construction period, rich structural styles and beautiful architectural image. With the inhaul cables by the new materials appeared, the inhaul cables method has gradually been the main way to prestress the steel structure. However, the inhaul cables are very easy to be subjected to the environmental corronsion and invasion which leads to the invalidity of the inhaul cables. On the other hand,with the passage of time, the inhaul cable will be flabbier and flabbier. The corrosion and relaxation of the inhaul cables will affect the structural performance, and even threaten the safety of the structure. Therefore, it is very important to study the influence of the inhaul cable corrosion and relaxation of the structure. This paper takes a cable supported barrel vault structure as an example to simulate the corrosion and relaxation of the inhaul cable, and study the effect of the structure in different conditions.Firstly, this paper introduces the basic concept, classification and research status of the prestressed steel structure, and then introduces the prestressed steel structure with the inhaul cables. At the same time, it makes a brief introduction of the reliability theory, summarizes the reliability theory present situation of the prestressed steel structure with the cables.Secondly, this paper introduces the research foundation and method of the structure reliability theory, it also explains the relationship between the reliability and reliability index of the structure, and introduces several common reliability calculation method.Thirdly, this paper uses Ansys to simulate the cable supported barrel vault structure, and calculate the maximum displacement of the structure and the maximum stress of the inhaul cables as well as the maximum displacement of the structure and the maximum stress of the inhaul cables when the inhaul has been corroded and relaxed, summarizes the change rule of the structure and studies the influence of the corrosion and relaxation on the structure.Finally, this paper uses the PDS module in Ansys to analyze the reliability of the structure by Monte Carlo method and Response Surface Method, calculate the reliability index and observe the linear correlation coefficient between the random input parameters and the random output variables. It also calculates the reliability index when the inhaul has been corroded and relaxed, summarizes the effect of the two damage on the structure and provides suggestion for the monitoring and maintenance of the prestressed steel structure with inhaul cables in the actual engineering.