ABSTRACT
The ductility and strength of concrete can be improved by lateral confining pressure from the hoops and steel sections in steel reinforced concrete (SRC) columns. In addition to the confinement effect, the Germans are taking advantage of the time-dependent effects of creep and shrinkage to increase concrete compressive strain. The Comite Euro-International Du Beton (CEB)-FIP Model Code Committee published CEB Model Code 90, which provides procedures for estimating creep and shrinkage strains. Creep is a nonlinear phenomenon. The creep coefficient can be used to describe the creep generated by a given duration of loading. Concrete creep depends on its composition and degree of hydration. Concrete creep decreases with decreasing water/cement ratio, decreasing cement paste content, increasing stiffness of the aggregates, and increasing degree of hydration at the age of loading. For SRC columns, the strain-compatibility issue also exists between high-strength steel and concrete.
