| No. Men. | |
| Loading and wheeling stone | 10 |
| Loading and wheeling sand | 3 to 4 |
| Loading and wheeling cement | 2 |
| Untieing and emptying cement bags | 1 |
| Charging cement to hopper | 1 |
| Operating mixer and hopper | 1 |
| Pulling down and tending discharge | 2 |
| Carrying concrete in shovels | 8 |
| Spreading concrete | 2 |
| Tamping concrete | 2 |
| Sweeping concrete | 1 |
| General laborers | 3 |
| Foreman | 1 |
| Watchman | 1 |
| Timekeeper | 1 |
| — | |
| Total gang | 40 |
This gang averaged 1,000 sq. yds. of 6-in. foundation per 10-hour day; a maximum of 1,400 sq. yds. was laid in a day. We have thus an average of 167 cu. yds. and a maximum of 234 cu. yds. of concrete foundation mixed and placed per 10-hour day. At an average wage of $2 per day the average labor cost of mixing and placing concrete was 48 cts. per cu. yd. or 8 cts. per sq. yd. of 6-in. foundation. It was stated that the gang was larger by three men than was ordinarily used owing to certain extra work being done at the time that the above figures were collected. Taking out three extra men and the timekeeper and watchman we get 34 men actually working in mixing and placing concrete. This reduced gang gives us a labor cost for mixing and placing of about 41 cts. per cu. yd. or 6.8 cts. per sq. yd. of 6-in. foundation.
FOUNDATION CONSTRUCTION USING A BATCH MIXER.—The following figures are an average of several jobs using a Ransome ½-cu. yd. mixer for constructing 6-in. foundations. The mixer was moved 1,000 ft. at a time and the work conducted 500 ft. in each direction from each station. The concrete materials were delivered from stock pile to mixer in wheelbarrows and the mixed concrete was hauled to the work in two-wheeled Ransome carts. Run planks were laid for the carts and one man readily pushed a cart holding 6 cu. ft. The men had to work fast on the long haul but had an easy time when the haul was short. The organization of the gang was as follows, wages being $1.50 per day:
| 10 men loading and wheeling stone | $15.00 |
| 4 men loading and wheeling sand | 6.00 |
| 2 men handling cement | 3.00 |
| 1 fireman | 2.00 |
| 1 man dumping mixer | 1.50 |
| 5 men wheeling carts | 7.50 |
| 3 men spreading and ramming | 4.50 |
| 1 foreman | 3.50 |
| ——— | |
| Total wages per day | $43.00 |
This gang averaged 1,080 sq. yds. of 6-in. foundation or 180 cu. yds. of concrete in place per day which gives a labor cost of 24 cts per cu. yd. or 4 cts. per sq. yd. for mixing and placing.
CHAPTER XV.
METHODS AND COST OF CONSTRUCTING SIDEWALKS, PAVEMENTS AND CURB AND GUTTER.
Next to pavement foundations the most extensive use of concrete in street work is for cement walks and concrete curb and gutter. Usually the mixing and placing of the concrete is hand work, practically the only exceptions being where pavement base, curbing and sidewalks are built all at once, using machine mixers. The same objections that have been raised to machine mixers in laying pavement foundation are raised against them for curb and walk construction, and owing to the much smaller yardage per lineal foot of street in walk and curb work these objections carry more force than they do in case of paving work. Another argument against the use of mixers is that both walk and curb and gutter work involve the use of forms and the application of mortar finish, the placing of which are really the limiting factors in the rate of progress permissible, and this rate is too slow to consume an output necessary to make a mixer plant economical as compared with hand mixing where so much transportation is involved. Concrete sidewalk and curb work are essentially hand mixing work; they, therefore, involve a careful study of the economies of hand mixing and wheelbarrow haulage which are fully discussed in Chapter II.