Layered approach for long-term deflections analysis of reinforced concrete beams

Abstract

In this paper, an attempt has been made to extend application of the integral constitutive model proposed by G. Kaklauskas to long-term deformational analysis of flexural reinforced concrete members. Constitutive relationships for compressive concrete and cracked tensile concrete used in the analysis are presented. The long-term behaviour of compressive concrete was modelled by modified Hognestad’s relationship. While for modelling of long-term behaviour of cracked tensile concrete a modified constitutive relationship proposed by G. Kaklauskas was used. A powerful approach for the time-dependent analysis of the cracked cross-section is adopted. Determination of long-time strains, stresses and deflections (curvatures) based on age-adjusted effective modulus method, a relaxation procedure and layered approach is briefly described. Statistical deflection calculation analysis has been carried out for a large number of experimental beams and it has shown a reasonable accuracy.