Geometrically and materially nonlinear creep behaviour of reinforced concrete columns

ABSTRACTA mathematical model is developed, which considers creep at the nonlinear range of stresses, shrinkage, aging, cracking, and the geometric nonlinearity in reinforced concrete columns. Creep is modelled through the modified principle of superposition that is based on the use of a stress-dependent compliance function. The governing equations are solved through numerical integration in time and the multiple-shooting method for the solution in space. An iterative procedure is used for convergence at each time step. A numerical study is conducted, which reveals the importance of considering the combined geometric and material nonlinear effects in the creep analysis of concrete columns.