Evaluation of Short-Term Deflections of Partially PrestressedConcrete Members

The paper reviews methods based on the effective moment of inertia approach, which have been proposed recently to calculate the short-term deflections of partially prestressed concrete members. The existing experimental data are analyzed, and the accuracy of these methods in predicting short-term deflections is studied by comparing the calculated deflections with the observed deflections of 55 partially prestressed test beams. By fitting the probabilistic models to the data, the variability of deflections predicted by each method is demonstrated, so that the method with least variability may be chosen to estimate deflections in partially prestressed structures. Finally, the design charts that simplify the calculation of decompression and cracking moments of partially prestresed concrete members are presented.