Predicting early age cracking of steel-concrete composite beams in partial interaction

Hydration heat and shrinkage of concrete at early age can be responsible for cracking phenomena developing in steel-concrete composite beams. Predicting these phenomena is a rather difficult task, as material properties and the actual interaction between the concrete slab and the steel profile evolve in time. Moreover, few contributions are actually available in the scientific literature and the recom-mendations adopted by design codes are generally simplistic. Therefore, this work deals with de-termining the time evolution of stresses and strengths in concrete at early age. Two different ap-proaches assuming either full or partial interaction between the concrete slab and the steel profile are considered. The results obtained by applying the two alternative approaches to a steel-concrete com-posite bridge assumed as a case-study are finally compared and discussed.