Title: Determining Time Dependent Losses Of Prestress with Due Consideration of Aging Coefficient and Percentage of Steel

Author(s): T. K. Bandyopadhyay and B. Sengupta

Publication: Journal Proceedings

Volume: 83

Issue: 2

Appears on pages(s): 236-243

Keywords: age; creep properties; modulus of elasticity; prestressed concrete; prestressing steels; prestress loss; stiffness.

DOI: 10.14359/10421

Date: 3/1/1986

Abstract:
Aging coefficient has been calculated by a numerical method using a step-by-step approach. The method takes the following into account to attain an unbounded value of creep strain: effect of steel ratio, stiffness coefficient of the member, creep coefficient, concrete aging, and variation of modulus of elasticity of concrete. The calculations are extended to determine the loss in steel stress, showing clearly the accuracy achieved due to the consideration of proper aging coefficient accounting for the reinforcement present which is normally not given due attention. A few steps of the approach are included in the Appendix to show the steps followed for arriving at final values us-ing a Burroughs 6700 computer.