Time-Dependent Deformation of Concrete and Its Uncertainty

点击翻译按钮获取中文摘要

This research program will lead to an improved mathematical model for creep and shrinkage of concrete, its probabilistic aspects, and its effects in structures. Constitutive relation, which takes into account strain-softening due to fracturing at variable humidity and stress-dependence of shrinkage and thermal expansion coefficients, will be developed. Creep tests at various moisture conditions and high temperatures will be conducted with six-inch cylinders in a unique, large triaxial-torsional testing machine with temperature control. Also tested will be creep of small hollow cylinders under triaxial-torsional load in which fracturing due to humidity variations is suppressed by prestress. Effects of cracking on the overall drying diffusivity of concrete will also be measured. Numerical algorithms for step-by-step finite element analysis will be formulated and verified numerically, and certain applications in structural analysis will be demonstrated.