Bulletin 14-86. U. S. Dent of Agriculture 
Plate 5 
Rail Clearance, Sight Distance, and Grade-Line Treatment are all 
Involved in the Location Problem 
A.— Superelevation of the bridge floor may expose a rail to impact from vehicles causing dam- 
age as illustrated 
B.— An example of poor bridge location and improper selection of type. To avoid a slight 
increase in span length, the locator has thrown excessive reverse curvature into the 
approach alignment. This coupled with the use of housed timber-truss construction 
restricts the sight distance. At a slight increase in cost a much better alignment could 
have been obtained and the use of steel-truss construction would have greatly improved 
the clear sight distance 
C— Poor floor drainage resulting from lack of camber 
