DESIGN DRAWINGS. 423 



Louvres. Note depth on design, and whether wood or metal, fixed or pivoted. If metal 

 give gage and kind of same. 



Corrugated Steel. Give gage and kind of all corrugated sheeting, painted or galvanized; 

 method of fastening, lining, etc. 



Gutters and Conductors. Show gutters, conductors and downspouts where necessary and 

 give size and kind and thickness of metal, methods of fastening, etc. 



Circular Ventilators. Show location on design and note size and kind. 



Roofing. Give kind of roofing material, and thickness of sheathing when used. 



Notes. Note on design the section of: (a) Purlins and form where trussed; (b) girts; (c) sag 

 rods; (d) lateral bracing; (c) end columns; (f) window posts; (g) door posts. 



Connections. In making a design be sure that all clearances and connections with adjoining 

 structures are properly provided for and that all dimensions necessary for detailing of same are 

 given on the design. 



DESIGNS OF PLATE GIRDER BRIDGES. 



Loads. Give assumed dead, live and wind loads, and show diagram of wheel loads. 



Diagram and Views. Show an elevation of girder with stiffeners, a plan with lateral bracing, 

 and a half end view and a half intermediate section. 



Stresses. Give maximum bending moments and maximum shears, maximum stresses, 

 required and actual net area of flanges, noting number of rivets deducted, and required net and 

 actual gross areasof webs. 



Dimensions. The following dimensions should appear on all plate girder designs. Distance 

 b. to b. of end angles, or distance out to out of girders, c. to c. of bearings, back wall to back wall, 

 or c. to c. of piers, b. to b. of flange angles, spacing of girders and track stringers, base of rail to 

 masonry, end of steel to face of back wall, angle of skew if any, and grade of base of rail. 



For girder bridges on curves give the curvature and super-elevation of outer rail and distance 

 from top of masonry to base of low rail. Give elevation of grade and of masonry on a vertical 

 line through center of end bearing. 



Rivet Spacing. Note on the elevation of girders the spacing of rivets connecting flange 

 angles to web, changing spacing at stiffener points. Give number of rivets in single shear for end 

 connections of all laterals and cross frames. 



Shoes and Pedestals. Give maximum reaction, required and actual area of masonry plate, 

 with allowable pressure on masonry. Note size of bed plate, and show in position with location 

 of holes for anchor bolts. Note size and number of rollers for expansion pedestal, and also whether 

 pedestal is built, cast iron or steel. 



Expansion Points. Mark fixed and expansion points and show whether pedestals or bearing 

 plate-* are to be used. 



Stiffeners. Show end and intermediate stiffeners on elevation of girder, giving sections and 

 stating whether fillers are used, or stiffeners crimped. 



Super- elevation. If the bridge be on a curve, show how the super-elevation of the outer 

 rail is to be cared for, whether by tapering ties, or changing height of pedestal or masonry plate. 



Track. Show track in place, noting such information as size and notching of ties and guard 

 timbers and manner of connecting timber deck to the girder. For through girder always show 

 clearance diagram with dimensions. 



Notes. (a) Material (whether O. H. (open-hearth) or Bessemer, soft, medium or structural 

 steel) ; (b) specifications (name and date) ; (c) size of rivets and holes, reamed or punched full size. 



DESIGNS OF TRUSS BRIDGES. 



Loads. Always give the following assumed loads on the stress sheets. 



Dead Loads. (a) Weight of track in Ib. per lin. ft. of track; (b) weight of trusses and bracing 

 per lin. ft. of bridge; (c) weight of stringer and stringer bracing per lin. ft. of bridge; (d) weight 

 of floorbeams per lin. ft. of bridge. 



