I am trying to find the deflection and moment formulas for a distributed load on a double span, with unequal lengths. The distributed load is equal on both spans.
I haven't found this loading condition as a canned case by itself. You could use superposition with case 1 being a single span distributed load and case 2 a single span with a negative unit point load at point of distance a from the left end. Solve for the deflection at point "a" for each case, set the deflections equal to eachother and solve for the true value of the interior support load. Sum moments and vertical forces to arrive at the exterior support loads.