Concrete Construction: Methods and Costs

by Halbert Powers Gillette; Charles Shattuck Hill

By hand—	Total.	Per cu. yd.
1 foreman ½ time at $3	$ 1.50	$0.025
4 men shoveling concrete at $1.50	6.00	0.100
1 man placing concrete at $1.50	1.50	0.025
1 man ramming concrete at $1.50	1.50	0.025
	———	———
Total	$10.50	$0.175
By machine—
1 horse and driver at $3	$ 3.00	$0.030
3 men pushing and unloading car at $1.50	4.50	0.045
5 men placing and ramming at $1.50	7.50	0.075
1 foreman at $3	3.00	0.030
2 men dumping mixer at $1.50	3.00	0.030
	———	———
Total	$21.00	$0.210

COST OF RETAINING WALL.—The following figures of the cost of a concrete retaining wall are given by C. C. Williams:

Cost of Material.
Kind and amount of material—	Unit Price.	Cost.
Stone, 441 tons	$ .70	$308.70
Sand, 182.5 yds.	.55	100.37
Cement, 536 bbls.	.85	453.60
		———
Total		$862.67
Lumber ¾ value		$205.33
Wheelbarrows, ¾ value, 6 at $3.50		15.75
		———
Total		$221.08
Excavation—
Labor, 4,002 hours at 15 cts.		$600.30
Carts, 800 hours at 12½ cts.		100.00
Foreman, 460 hours at 35 cts.		171.00
Waterboy, 240 hours at 10 cts.		24.00
		———
Total		$895.30
Concrete—
Labor, 2,398 hours at 15 cts.		$359.70
Foreman, 224 hours at 35 cts.		77.40
		———
Total		$437.10
Handling material—
Unloading cars, 380 hours at 15 cts.		$ 57.00
Foreman, 40 hours at 35 cts.		14.00
		———
Total		$ 71.00
Forms—
Carpenters, 997 hours at 22½ cts.		$224.33
Work to support bridge—
Carpenters, 542 hours at 22½ cts.		$121.95
Labor, 458 hours at 15 cts.		68.70
		———
Total		$190.65
Superintendence and office—
Superintendent, 30 hours at 50 cts.		$15.00
Office		20.00
		————
Total		$35.00
		————
Grand total		$2,937.13

Proportional costs—
Item.	Cost.	Cost Per Yard of Concrete.	Per Cent. of Total Cost.
Concrete materials	$ 862.67	$2.02	46.7
Laying concrete	437.10	1.03	23.4
Lumber	205.33	.48	11.3
Building forms	224.33	.53	12.3
Handling material	71.00	.17	03.8
Wheelbarrows	15.75	.04	01.0
Supt., etc.	35.00	.07	01.5
	————	——	———
Total	$1,851.18	$4.34	100.00
Work on bridge	190.65
Excavation	895.30
	————
	$2,937.13

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CHAPTER XIV.

METHODS AND COST OF CONSTRUCTING CONCRETE FOUNDATIONS FOR PAVEMENTS.

Contractor's skill or want of skill in systematizing and managing labor counts as high in street work as in any class of concrete construction. As previously demonstrated, the cost of mixing is a very small portion of the labor cost of concrete in place; the costs of getting the materials to the mixer and the mixed concrete to the work are the big items, and in street work the opportunity for increasing the cost of these items through mismanagement is magnified by the large area of operations involved per cubic yard of concrete placed. One cubic yard of concrete makes 6 sq. yds. of 6-in. pavement foundations and 100 cu. yds. of concrete make a 6-in. foundation for 300 ft. of 30-ft. street, while 4 to 5 cu. yds. will build 100 ft. of ordinary curb and gutter. Thus the haulage per cubic yard is considerable at best, and lack of plan in distributing stock piles and handling the concrete can easily result in such increased haulage expenses as to change a possible profit into a certain loss. A little thought and skill in planning street work pays a good profit.