Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

168 Molesworth’s pocket-book Distribution of Load on Abutments. Form a polygon of forces as follows:— With any convenient scale on the vertical line EF set out lengths corresponding to the loads, and from the points so obtained draw lines radi- ating to any convenient point G. Then from, the vertical lines that pass through the centres of the loads, draw lines parallel to the radiating lines, as shown in the diagram (the lines of the polygon having the same letters as those of the radiating lines to which they are drawn parallel). Join M N, and from the point G draw the dotted line G n parallel to M N, then the load on each abutment may be scaled off from the intersection of G n with E F. By calculation, the load on the right abutment A <z 4- B b 4- C c + I) d Span Load on left = total load - load on right.