Tensile Creep of Concrete: Study of Its Sensitivity to Basic Parameters

There is little data available in regard to concrete tensile creep, a property which can considerably influence shrinkage-induced cracking, for instance, in repair works. The authors examine findings of testing to evaluate the influence, on concrete tensile creep, of paste content, steel fiber reinforcement, age at loading, and stress level. The results indicate that concrete creep in tension, as in compression, sharply increases under drying conditions. The results also show that with age at loading, there is a decrease in tensile creep coefficient, and that, either under sealed or drying conditions, and up to half of the ultimate short-term strength, concrete tensile creep varies linearly with applied load. Compressive creep is apparently less sensitive to fiber reinforcement than tensile creep, and it was observed that as paste content decreased, tensile creep increased. Particularly to determine ultimate creep capacity, further research is necessary, but there are indications through reported data that optimization of cement-based repair materials could be possible to reduce cracking potential when subjected to restrained shrinkage.