Fig. 228.—Channel Section Wall Column for Factory Building.
This gives us a cost per cubic yard of concrete for materials and labor constructing forms of $480 ÷ 370 = $1.30, and per square foot of outside wall area of $480 ÷ (146 × 80) = 4.1 cts.
The erection and taking down of the forms, owing to the weight of some of the pieces, was done by means of special derricks. The footings were brought to within ½ in. of grade and a tenon form of the exact shape of the channel section of the column was placed on top and filled with grout to a depth of 1 in. These tenons served as guides in setting the column forms, and proved to be much quicker and more accurate than points.
Fig. 229.—Footing for Wall Column Shown by Fig. 228.
The forms were assembled on the ground and erected by a 35-ft. A-frame derrick mounted on wheels. The construction is shown by Fig. 231. This derrick had a capacity of about 4 tons and carried a Ransome friction crab hoist driven by a 5 h.p. Meitz & Weiss kerosene oil engine. It was the practice to set a number of forms before filling any. This enabled the carpenter gang to be plumbing up the first form while the erecting gang were setting others. The forms had to be very securely guyed and braced to withstand the impact of the falling concrete. Very little trouble was had in keeping them well lined up.
Fig. 230.—Form for Molding Wall Column Shown by Fig. 228.