Fig. 95.—Details of Pier for Calf Killer Elver Bridge.
Slag and sand were delivered to the mixer by means of wheelbarrows. The mixer was so placed that it would dump onto a platform, and the concrete could then be shoveled into a specially designed narrow-gage car. This car ran on one rail of the main track and an extra rail outside. A turnout for clearing passing trains was provided at both ends of the bridge. The track over the bridge from the mixer had a descending grade of about 1 per cent., so that with a little start the concrete car would roll alone down to the required points on the bridge. Only in returning the empty cars to the mixer was it necessary to push them by hand, and then only for a distance of never more than 400 ft.
Over the piers on the bridge in the center of the concrete car track openings were sawed to let the concrete pass to the forms below. To get the concrete into the forms, there were used zig-zag chutes with arms about 10 ft. long, which sections were removed as the concrete in the forms was increased. These chutes were a convenience by their ends alternating from one side to the other as the arms were removed in coming up.
The cost of the concrete work was as follows:
| Unloading Material. | ||||
| Rate per day. | Total days worked. | Total. | Per cu. yd. concrete. | |
| Foreman | $3.40 | 5 | $17.00 | $0.04 |
| 11 laborers | 1.368/10 | 52 | 71.14 | .15 |
| —— | ||||
| Total for unloading material | $0.19 | |||
| Building Forms, Bins, Etc. | ||||
| Foreman | $3.40 | 18 | $61.20 | $0.14 |
| 9 carpenters | 2.25 | 166 | 373.50 | .81 |
| New lumber, 23.7 M. ft. at $17.80 | 421.86 | .92 | ||
| Old lumber, 6 M. ft. at $8.33 | 49.98 | .11 | ||
| —— | ||||
| Total for building forms, bins, etc. | $1.98 | |||
| Cofferdam Excavation (45 cu. yds.) | ||||
| Foreman | $3.40 | 8 | $27.20 | $0.06 |
| 9 laborers | 1.156/10 | 74½ | 86.12 | .19 |
| —— | ||||
| Total for cofferdam excavation | $0.25 | |||
| Cofferdam Concrete (37 cu. yds.) | ||||
| Foreman | $3.40 | 8 | $27.20 | $0.06 |
| 11 laborers | 1.363/10 | 79 | 107.68 | .23 |
| Cofferdam lumber, 2.25 M. ft. at $20.00 | 45.00 | .09 | ||
| —— | ||||
| Total for cofferdam concrete | $0.38 | |||
| Concrete Mixing and Placing. | ||||
| Foreman | $3.40 | 30 | $102.00 | $0.22 |
| 9 laborers | 1.156/10 | 282 | 325.99 | .71 |
| Cement, 452 bbls. at $1.55 | 701.00 | 1.52 | ||
| Slag, 437 cu. yds. at $0.20 | 87.40 | .19 | ||
| Sand, 220 cu. yds. at $0.30 | 66.00 | .14 | ||
| —— | ||||
| Total for mixing and placing | $2.78 | |||
| Taking Down Forms and Clearing Up. | ||||
| Foreman | $3.40 | 13 | $44.20 | $0.09 |
| 11 laborers | 1.17 | 1.43 | 107.31 | .36 |
| —— | ||||
| Total for taking down forms, etc. | $200.00 | $0.45 | ||
| Engineering and supervision | .43 | |||
| —— | ||||
| Grand total, 460 cu. yds. concrete | $6.46 | |||
The wages given are the average wages. The men worked a 10-hour day. The concrete was a 1-3-6 mixture. The cofferdam work was done in connection with the construction of the fourth pier, this pier being the only one coming in the bed of the river to be built entirely new. The work on this was started in water about 6 ft. deep. The 37 cu. yds. of concrete is included in the total of 460 cu. yds. in the above tabulation. By itself the cost of the cofferdam work, not including cost of cement, sand and slag was as follows:
| Total. | Per cu. yd. Concrete. | |
| Lumber | $ 45.00 | $1.21 |
| Labor, excavating | 113.32 | 3.06 |
| Labor, concrete | 134.88 | 3.64 |
| —— | ||
| Total 37 cu. yds. concrete | $7.91 |
