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The Development of a Mathematical Model to Predict the Flexural Response of Reinforced Concrete Beams to Cyclic Loads, Using System Identification.
Stanton, J. F.; McNiven, H. D.
National Science Foundation, Washington, DC., January 1979, 210 p.
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This report describes the development of a mathematical model to predict the flexural response of reinforced concrete beams to cyclic loads. The objective is to take the first step towards the construction of a model which will predict accurately the nonlinear response of reinforced concrete framed structures when they are subjected to dynamic loads such as seismic disturbances. The model is constructed using system identification. The process consists of selecting a form for the model, and then using suitable mathematical techniques to adjust the numerical coefficients within it so that it reproduces as closely as possible the results of experiments. The first essential is to understand the physical behavior to be reproduced. The response of reinforced concrete members to large cyclic loads is nonlinear and inelastic and it changes throughout the history of the load. Because it is so complicated, the physical behavior of the material and mechanics which underlie it are investigated in considerable detail. A model form is then selected which divides the member into hypothetical layers. The material in each layer obeys an appropriate nonlinear constitutive law and the number forces are derived by integration across the cross section. The individual model which describes the steel behavior was developed especially for the purpose and is of particular interest.
Stress strain diagrams; Reinforced concrete; Beams (Supports); Algorithms; Mathematical models; Earthquake engineering; Computer programming; Stress analysis; Cyclic loads; Earthquakes; Dynamic structural analysis