With regard to a distributed load, the following conditions may be observed :
The load between a and c is half of it borne by the pier a direct, and half
of it is transmitted through the strut c d ; hence in this case the direct strains
are half what they would be if the load were concentrated ; theref(»« if W
equals the total load, the strains will be as follows : —

W

Strain on strut c d — -o"

Strain on tension rod




== 4 sin f

"W
Strain on horizontal member = -r- cotan i

4

Pig. 5 represents another form of
truss, somewhat similar to the former
in principle, but with the tension-
rods so arranged that the strain
upon them is proportionately less.
Let I equal the angles e a ^, or d hf^ and let the truss be loaded with two
weights, each equal to W ; placed, one at the point c, and the other at the point d.
