Finite Element Analysis And Damage Detection On Pre-stressed Reinforced Concrete Beam With Crack

With the rapid development of modern economy, more and more high-rise buildings and long-spans have been built and developed. Many structures become aging with the growth in service time, such as loads,fatigue,corrupted,aging and other factors.Damnification would be more and more stricter, Indeed the structure would broken out suddenly. So it is important to detect the damage of the structure.Damage detection according to vibrate has been successfully used in common concrete structure, This method is based on the changes of dynamic characteristic fore and after damage .Compared with common reinforced concrete beams, force of prestressed tendons directly influences dynamic characteristic of structure members. Force of prestressed tendons, crack, and the location of the tendons are all related with the natural frequency.In this paper, we give the theory,method,process of that the calculation of prestress and modal, and the theory that how to detect the damage.We use finite element to simulate prestressed force, crack, location of the tendons and obliquity of the crack. Through the calculation result we know that prestressed force, crack, location of the tendons and obliquity of the crack all have the relationship with the frequency.Also we can detect the damage with modal method. All of what we have get are good for project.