RELATIONSHIP BETWEEN CRACK WIDTH AND HYPOTHETICAL TENSILE STRESS OF PARTIALLY PRESTRESSED CONCRETE MEMBERS

Abstract

The estimation of crack width is one of the most important tasks in designing partially prestressed concrete (PPC) members. However, this task, which includes calculation of crack spacing, average steel stress etc., is very tedious using current existing procedures. In this paper, relationship between crack width and hypothetical tensile stress was derived in order to simplify control of crack width in reinforced conctrete and PPC members. The hypothetical tensile stress is calculated on the assumption that the entire section is still effective even after cracking has occurred. The instantaneous and long-term crack widths are calculated by using the PPC Recommendation of Architectural Institute of Japan. Factors which had been taken into account in developing procedure of this method are: concrete strength, ratio of reinforcement, depth of beam, concrete cover depth, prestress, shrinkage and creep.