60 .374 838
70 .404 905
80 .434 972
90 .464 1039
100 .494 1106
120 .554 1241
140 .614 1375
150 .643 1440
160 .673 1507
170 .703 1575
180 .733 1642
200 .792 1774
225 .867 1942
250 .940 2105
275 1.013 2269
300 1.087 2435


The weight of a single track railway bridge may be taken as equal to
that of a double track highway bridge,--and the trusses that will be
large enough for one will be large enough for the other.

The greatest load that a highway bridge can be subjected to is 120
lbs. to the square foot of surface.


TABLE OF CAMBERS FOR BRIDGE TRUSSES.

Span. Camber. Span. Camber. Span. Camber. Span. Camber.
feet. Inches. Feet. Inches. Feet. Inches. Feet. Inches.