The analysis of the raft floor of a barrage poses a challenge to engineers due to varying foundation strata, combination of loads and functional requirements. The present study embodies the analysis of the raft floor of a barrage using two approaches viz., the Hetenyi’s and finite element method (FEM) involving varying foundation media. Moments at different discrete points along the raft of the barrage have been calculated by Hetenyi’s method and FEM, and a comparison has been made for typical representative load cases involving gravity loads and differential hydrostatic pressures. Significant differences have been observed in the moments obtained by both the methods. Hetenyi’s method could be misleading, as it does not consider the variation and continuation of foundation media along the horizontal and vertical direction of the raft. In the light of the shortcomings of the Hetenyi’s method, which may provide preliminary design estimates, a finite element analysis of the barrage seems a better alternative for final design. Results also imply that the recommendation of IS 11130-1984 for the analysis of barrage raft floor using Hetenyi’s method, which does not consider variation of foundation media, merits scrutiny.
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