ENGINEERING 
624 Bridges and roofs Viaducts 
Subdivide if wisht like 620.1-.9 and 620.0 
General 
Purpose 
Highway, foot bridges, etc. regardless of structural type 
1 
J 
12 
Location Approaches 
Foundations 
General works Foundations of bildings are better clast 721.1 
Foundation bed Nature of soil 
Excavation, timbering, shoring 
624.153~.157 may be subdivided like 721.13-.17 
Material for bilding foundations 
For material for superstructure see 624.01 
Pile foundations: general Material 
" “ methods of sinking 
Platform foundations 
Subaqueous foundations 
Processes: cofferdam, caisson, freezing 
Piers and abutments 
Wood, masonry, metal. Subdivided like 620.1 
Stresses and strains 
General; if limited to a special type, class with that type 
ITI General Computation of stresses 
172 Loads 
Ded, live or moving loads 
Highway 
Railway 
Wind pressure 
Working stresses 
Girders and girder bridges 
Including floor systems; see .25 below 
Girders 
Continuous; discontinuous or independent 
Solid beams 
Wood 
Metal 
Plate girders Lattis girders 
Trestles 
Floor systems 
Girder bridges 
Trusses and trussed bridges 
Constructed of systems of braced girders 
I3 
14 
Ig 
JI73 
174 
I78 
176 
2 
IT 
22 
222 
227 
23 
24 
27 
q 
r 
’ 
3I 
32 
33 
35 
a 
Simple truss 
Continuous truss 
Cantilever truss 
Tubular bridges 
Balance bridge 
Box-girder bridge