Flexural creep in plain concrete: State of the Art

Concrete, being a viscoelastic material, creeps with time causing additional strains and deflections in flexural members. Most of the studies in creep of concrete are based on long-term tests on plain concrete standard cylinders under axial compression, very limited studies have been reported on creep of concrete in flexure and direct tension. Whether the mechanism of creep in tension is different from creep in compression is still being debated. Numerous studies have been reported in the literature showing varied results with regard to the effects of creep in direct compression, direct tension and flexure. This paper provides a brief review of various creep tests on plain concrete reported and attempts to understand the effects of various parameters on the creep behaviour of concrete. Some studies reported that the creep in tension is higher than that in compression, whereas a few others obtained contradictory results from creep tests. This may be attributed to the fact that the relative creep behaviour in tension and compression is highly sensitive to the material composition, exposure conditions and loading level. The studies by various researchers on flexural creep in plain concrete are also discussed.