The document summarizes an experimental study on the flexural behavior of reinforced concrete beams with different percentages of Ground Granulated Blast Furnace Slag (GGBS) as a partial replacement for cement. Twelve beams were tested with 0%, 30%, and 40% GGBS replacement at 28 and 56 days. The study found that while beams with GGBS had lower ultimate loads than plain cement beams at 28 days, the loads increased with age and were equivalent to plain cement beams by 56 days. Deflections of GGBS beams under service loads were also comparable to plain cement beams by 56 days. The structural behavior and failure patterns of GGBS beams resembled those of plain cement beams. Thus, the study concluded that G