Abstract
Decrease of initial prestress in prestressed concrete members is caused by the creep and shrinkage of concrete with the lapse of time after initial prestress is transferred. So, the actual plastic deformation in concrete section can be considered as the shrinkage and the creep of concrete under the action of both constant and time-variable stresses. From this concept, the general solutions on loss in initial prestress were derived in simplified form, which can be applied to the any type of prestressed section with many layers of prestressing tendons as well as with or without additional reinforcement. Additionally, the prestress loss under the action of both prestressing force and design loads was discussed for applying the general solutions presented here to the estimation of prestress loss in statically indeterminate prestressed members. An example was also worked out to demonstrate that the accurate estimation of prestress loss can be done from the Authors' equations.
