Tributary loading or tributary width is the accumulation of loads that are directed toward a particular structural member. Example: Tributary width is 7 ft + 5 ft = 12 ft. If the load is 100 PSF, the load to the beam would be 12 ft x 100 PSF = 1200 PLF.

What is tributary width?

The tributary width for B1 is the distance from the centerline of the beam to half the distance to the next or adjacent beam, and the tributary area for the beam is the area bordered by the tributary width and the length of the beam, as shaded in the figure.

How do you find the tributary width of a girder?

Graphically, we can draw a line down the center of each supported joist and say that all the area between the line and the girder is tributary to the girder. You can see this in Figure TA. 2.6. The distance of the tributary area in the direction of the joists is the tributary width.