Bridges

Accelerated curing of high-strength concrete is commonplace in the rapid construction of prestressed concrete bridge girders. Heat curing is preferable in attaining early-age strength of the concrete for prestress transfer, however its time-dependent behaviour in the post-curing stage remains unexplored. This paper examines the time-dependent behaviour of heat-accelerated cured concrete used for the casting of precast prestressed concrete bridge girders. Creep and drying shrinkage tests were performed for the different regimes to compare the effects of heat treatment on the time-dependent behaviour of high-strength concrete within the early-age period (0 – 180 days).

Results were compared to predictions made by AS 5100.5-2017 Amd.2 to assess the suitability of the current creep and shrinkage models to heat-cured concrete. The results to date demonstrated a divergence of the code provisions in the prediction of the creep and drying shrinkage behaviour of high-strength concrete and recommendations for further investigations are made in accurately forecasting the effects of curing on time-dependent behaviour.