COST OF CONSTRUCTION CRUSHED STONE ROAD.The cost of construction of a crushed-stone road varies greatly with the size of the job, the con ditions of the material and labor markets, the specifications under which the work is done, etc.; and any general statements must be considered only as approximate for any particular case.
ofQuarrying. The cost of quarrying will vary with the amount of stripping, the hardness of the rock, the depth of face, the method of quarrying (hand tools or explosives), the method of drilling (hand or power), etc. For hard limestone, the cost of quarrying, exclusive of quarry rent, pumping, and superintendence, was as in Table 21, page 235.
Table 22, page 235, gives the detailed cost of quarrying road stone in Great Britain. Wages were probably less than in Amer ica, and probably the labor was correspondingly less efficient. In quarry No. 1, the rock was " highly siliceous and very seamy iu parts, 60 per cent being very hard and solid." In No. 2, the rock was " hard and tough, and seamy in places."_ No. 3 was a " hard and very tough basalt." For additional data on the cost of quarrying, see the first part of Table 23, page 237.
The cost of setting a telfold foundation will vary greatly with the character of the stone and with the amount of knapping and wedging done. If the founda tion stones are laminated, they will fit well one against the other, and consequently require comparatively little wedging, but if the stone is unstratified and breaks in irregular pieces, more labor will be required to place it and to break off projecting points and to wedge the stones. On the Hudson County Boulevard (Jersey City. N. J.) three men set, dressed, and thoroughly wedged about 3 square yards of trap telford foundation per hour, the stone being wheeled from the side, at a total cost for labor of about 15 to 18 cents per square yard. With a soft, bedded stone, the cost is only about 5 to 6 cents per square yard.
On the state-aid roads in Massachusetts, in 1899 the average contract price for a 6-inch telford foundation in place was 34 cents per sq. yd., the minimum being 30 cents and the maximum 50.* Cost of Crushing. The cost of crushing varies with the amount of the output, the arrangement of the plant (§ 330), the hardness of the stone, the price of labor and supplies, etc. Table
23, page 237, gives the details for four kinds of stone. Notice that for the ledge stone, the output. was 80 to 100 cubic yards per day, and the cost of crushing was 20 and 21 cents respectively. If the output is decreased, the price will be slightly increased, and vice versa. A study of numerous data seems to show that the above is fairly representative, except that frequently the prices paid for labor are less.
Crushed limestone is occasion ally sold f.o.b. at the quarry as low as 35 to 40 cents per ton (about 47 to 53 cents per cu.
and frequently as low as 45 to 50 cents per ton (60 to 65 cents per cubic yard). The cost of crushed trap f.o.b. at the quarries in New Jersey, for several years previous to 1900, was 40 to 50 cents per ton; but in that year it was increased nearly 50 per cent.$ In Massachusetts, the cost of broken trap varies from $1.10 to $1.60 per ton (about $1.47 to $2.13 per cu. yd.) on cars at the end of the railroad transportation.* In Boston, the cost of crushed granite delivered on the streets is $1.65 to $1.90 per ton. In Montreal, syenite macadam delivered on the street costs an average of $1.15 to $1.20 per ton.
We will assume that the wages of driver and team is 30 cents per hour, although in cities it will usually be more than this. A load will vary from 1 to 1§ cubic yards, the for mer on soft roads and the latter with good ones; and we will assume that 11 yards is an average load. When the stone is stored in bins, it will require about 5 minutes to load; and an equal time will be consumed in dumping. The cost of the.time consumed in loading and unloading, then, is one sixth of the hourly wages of the team and driver, or 5 cents per load, which is equal to four cents per cubic yard. The team can easily travel 21 miles per hour, or 220 feet per minute; but to allow for little delays, we will assume that the team averages 100 feet and return per minute, at a cost of 0.5 cents per load or 0.4 cents per cubic yard. The cost of hauling, then, is 4 cents for loading and dumping plus 0.4 cent per 100 feet of distance hauled. This is equivalent to 25 cents for a haul of 1 mile.