UNIVERSAL PORTLAND CEMENT CO. 
85 
The ends of the reinforcing bars must be sufficiently long, so that 
each alternate rod can be turned back into the floor, 1 inch below its top 
surface, a distance of one-quarter the diameter of the tank and pointing 
towards the center, i. e., in a silo tank 16 feet in diameter, the alternate bar 
would be bent up from the bottom of the tank floor 8 inches, then turned 
back just under the top surface of the floor and running towards the 
center of the silo a distance of 4 feet. The remaining floor rods will be 
bent straight up, extending vertically a distance of 2 feet into the tank wall. 
The reinforcing should be supported about an inch above the plat- 
form, on small cubes of concrete or strips of wood placed about 2 feet 
apart. Cement and sand mortar mixed in the proportions of 1 :3 should 
then be put on and worked under the reinforcing to a depth of about one 
inch, and the concrete immediately placed upon this. In case small wooden 
strips are used to support reinforcing, these may be withdrawn from the 
underside of the floor as soon as the framing is removed, and the resulting 
holes filled with mortar. Concrete cubes are preferable to wooden strips, 
and may be easily made in the following manner: Lay down two 1-inch 
boards on a flat floor, one inch apart, and fill in the space between them 
with 1 :3 mortar, trowelling off the top. The long strip of concrete thus 
formed may be broken up into short sections approximately cubical in shape. 
After the floor has sufficiently hardened, the forms and scaffolding 
should be taken down, the wall forms hoisted up the outside, and placed in 
. position on the tank floor. Before concreting is continued on the 
Walls walls, the surface must be cleaned off, thoroughly moistened, and 
painted with cement and water grout, mixed about as thick as 
cream. The concrete must then be placed before the grout shows any 
tendency to dry. Six feet will be found a convenient depth for the tank. 
The vertical reinforcing above the tank floor is put in the same as be- 
low, with 3^-inch rods, spaced at intervals of 3 feet around the circum- 
. ference. The spacing for the horizontal rods may be obtained 
^ ^ from the chart on page 86. By referring to the diagram, it 
will be seen that the vertical scale shows the distance from the top of the 
tank, each small division representing one inch. Across the top of the table 
are the tank diameters, running from 10 to 16 feet. The heavy black lines 
indicate the spacing of the rods. This diagram may be conveniently used 
for tanks six feet deep or less. 
Suppose it is desired to know the proper reinforcing for a tank 14 feet 
in diameter and 6 feet deep (to hold 5 feet of water) . Running across 
Example horizontal column until 14 feet is reached, we find (direct- 
ly below) that two sizes of rods — ^-inch and 3^-inch — are used. 
Running to the bottom of the vertical diagrams, it will be seen that a %- 
inch rod is placed 2 inches from the floor fine. The next two rods are also 
^-inch, spaced 7 and 14 inches above the flrst rod. Above this point 34- 
inch rods may be used to the top, as shown, or three more ^-inch rods may 
be used, and the change made to 34-inch rods at a point 2 feet 5 inches from 
the top. 
The intake and outlet pipes should run up one corner of the chute, 
far enough from the wall so that they may be covered to prevent freezing. 
