Creep and shrinkage models for railway prestressed concrete sleepers: A review

Creep and shrinkage of railway prestressed concrete sleepers play vital role in serviceability performance required for safe and reliable operations of a railway line. The time-dependent effects depend largely on various environmental and loading condition factors. Many investigators in the past have proposed various material models to predict creep and shrinkage effects but those were mostly applied to general reinforced concrete members. In contrast, prestressed concrete design needs a suitable model for predicting the time dependent behaviour of prestressed concrete structures such as long span bridges, stadiums, silos and confined nuclear power plants, etc. This paper highlights the constitutive models, which have led to predictive models that could be realistically applied to prestressed concrete. This paper presents a critical review of creep and shrinkage effects on railway prestressed concrete sleepers. Three common design codes have been considered, including European Standard EUROCODE2, American Standard ACI and Australian Standard AS3600-2009. The study results show that EUROCODE2 and AS3600 are very coherent and consistent. The paper also highlights the construction and practical issues as a result of undesirable creep and shrinkage effects at different time frames.