Analytical models and an efficient numerical procedure are described for the material and geometric nonlinear analysis of reinforced and prestressed concrete rigid frames, slabs, panels, thin shells, and three-dimensional solids. Time-dependent effects due to load history; temperature history; creep, shrinkage and aging of the concrete; and relaxation of the prestressing steel are included in the analysis. Any combination of nonprestressed and prestressed reinforcement may be specified so that partial and fully prestressed cases may be analyzed. The prestressing may be provided by either pretensioned or bonded and unbonded post-tensioned tendons having general geometric layouts. Loss of prestress due to various effects, including friction, are taken into account. Brief descriptions of four computer programs developed at the University of California, which are capable of performing the above analyses, are given in the Apendix.
