I'm trying to plan a DUPLO train track layout to order but I currently don't own any pieces. I'd like to include a bridge like the one in set 3774, but I'm unsure if it will fit my layouts.
Based on the layouts from this answer, a half-bridge seems to be 2 straight tracks + 1 quarter-circle (split mid-track at the end, because the middle of the bridge is centered with the crossing track below it).
From this guy's measurements, a quarter-circle of the newer DUPLO tracks is about 18x18 studs. Straights are 8 studs long.
So, a half-bridge should be 32 studs (16+8+8), or 4 straight tracks. The full bridge would be 64 studs, or 8 straights.
I don't have the pieces to confirm these measurements.