Serviceability behavior of Normal Strength Concrete (NSC) and High Strength Concrete
(HSC) T-beams was experimentally evaluated. The crack pattern was observed, the effect of
flange dimensions (breadth and thickness) on the crack pattern and load-deflection response
was evaluated experimentally for 10 beams comprising the two studied groups, NSC and HSC
T-beams. The short-term deflections were measured experimentally and predicted empirically
under mid-span concentrated loading. It was found that increasing the flange width and
thickness resulted in higher loads and lower deflections under service loads to a different
extent. Prior to failure, the increment in the maximum loads was up to 22% while the
deflection reduced by 31% for NSC and 23% for HSC beams. The available equations for
determining the effective moment of inertia (Ie) were reviewed and used in predicting the Ie of
the cracked beam. The results were compared with the experimental values (Iexp). The Ie
showed a noticeable difference, especially for the HSC T-beams. New equations were
proposed in which the tensile reinforcement ratio was considered. Compared with the other
available equations, the proposed equations demonstrated a better agreement and
repeatability of predicting experimental results studied herein. In addition, the proposed
equations were used to predict the Ie for experimentally tested T-beams available in the
literature. The proposed models showed a high degree of accuracy