An analytical model for the seismic analysis of reinforced concrete frame structures

Includes bibliographical references.The thesis is concerned with developing an analytical model to describe the cyclic behaviour of reinforced concrete members. The mechanisms which are important in the behaviour of members dominated by flexural deformations are identified. They include bar-slippage due to deterioration of the bond between the steel and concrete, the crack opening and closing criterion, and the cyclic response of steel and concrete. All these mechanisms are incorporated in an analytical model based on a layered beam approach. The model is developed for a member in double curvature bending and consists of two inelastic zones on either side of a central elastic zone. The bar-slippage which occurs in the beam-column joint is included at the ends of the beam model. A linear bending moment distribution is assumed along the beam. The moment-curvature relationship is calculated in the inelastic zones; the curvature is then integrated along the inelastic zone to determine the displacements. Damage measures with an objective of predicting the onset of failure are also proposed. The implementation of the model into a frame analysis computer program is discussed. Special attention is devoted to the solution strategies and numerical algorithms employed in the computer program. The model is shown to perform satisfactorily when compared to experimental results. A simplified analytical model which approximates the concrete with only two layers is also presented. The simplified model is shown to predict the response as competently as a model with far more concrete layers; however, the computational time for the simplified model is significantly less