Fig. 233.—Arrangement of Derricks for Erecting and Stripping Forms.
Summarizing the above figures we have the following cost per cubic yard of concrete in place:
| Item. | Per cu. yd. |
| Concrete materials | $3.00 |
| Reinforcing steel | 0.73 |
| Forms, lumber and framing | 1.30 |
| Forms, erecting and concreting | 0.81 |
| Forms, assembling and reinforcement | 1.56 |
| Forms, stripping | 0.63 |
| Mixing and wheeling concrete | 0.83 |
| —— | |
| Total | $8.86 |
CONSTRUCTING ONE-STORY WALLS WITH MOVABLE FORMS AND GALLOWS FRAMES.—In constructing the walls for an 85×30-ft. factory building at Old Bridge, N. J., Mr. A. E. Budell made use of movable forms and gallows frames to construct the curtain walls and columns in one piece. Each side wall was built its full height in successive 50-ft. lengths by depositing the concrete between two forms which were moved upward as the concreting progressed. Fig. 234 indicates the mode of procedure. The form was raised and lowered by means of two gallows frames fitted with blocks and tackle. A steel cable, with a trolley affixed, extending from one frame to the other, provided a convenient mode of hoisting material to the form, and the gallows frames took the place of ladders for climbing onto the structure. No scaffolding whatever was used and only one man was required overhead to dump the buckets and tamp the concrete into place.
Fig. 234.—Gallows Frame Supporting Wall Form Panels for One-Story Building.
Fig. 235.—Details of Wall Form Panel for One-Story Building.