EX&MPI.E OF REINFORCED CONOEXTE Ping. Illinois Cen tral Railroad. Fig. 148 shows one of the reinforced concrete channel piers of the Illinois Central Railway's double-track bridge across the Tennessee River, at Gilbertsville, Ky.t The reinforcement throughout consists of 3-inch square cor rugated bars (b, Fig. 28, page 236). In the foundation the bars are placed 6 inches above the bottom, in each direction midway between consecutive lines of piles. The entire pier is reinforced by horizontal rings, about 6 inches from the outside of the concrete, spaced ver tically 2 ft. center to center, except that there are three rings in the coping and corbel course. The coping has bars spaced 2 ft. center to center each way 6 inches under the top surface. The pier also has a system of vertical rods spaced 2 ft. center to center all around the pier, except in the footing and foundation where the spacing is a little greater. Joints in adjacent lines of reinforcement are not less
than 5 ft. apart. • At their junction the bars are lapped at least 18 inches and are tied with at least two turns of a No. 16 galvanized wire. All intersections are tied likewise.
The forms were constructed of sheeting, studding, and horizontal wales. The opposite waleing pieces were bolted together with rods running through the pier, each rod being in three pieces with a sleeve-nut near the surface of the concrete on each side. The curved ends of the piers were formed somewhat as shown in Fig.
The following is the actual cost of excavating 433 cu. yd. of earth and placing 130 cu. yd. of plain concrete for a highway bridge pier near Huntley, Montana, during weather so cold as to necessitate the heating of the water, sand, and gravel.* The forms were made of 2-inch lumber dressed on one side and beveled on the edges.