Deflection prediction of reinforced concrete beams by design codes and computer simulation

The paper statistically investigates accuracy of predictions of short-term deflections. The comparative study was based on the predictions made by design codes (Eurocode 2, ACI 318 and the new Russian code SP 52-101) and a numerical technique (finite element software ATENA). Unlike the previous investigations, the present research considers the influence of reinforcement ratio, load intensity and the shrinkage effect on the prediction results. This analysis has employed data of nine experimental programs, in total 80 specimens and 2233 measurement points. Deflection predictions varied significantly (in a statistical sense) with change in load intensity and reinforcement ratio and improved with increase of these parameters. Significantly larger prediction scatter was obtained for the members with small reinforcement ratio (p ⩽ 0.4%) and at early cracking stages. It was found that accuracy of numerical predictions based on finite element modelling improved after concrete shrinkage was taken into account.