OFFICE OP PUBLIC ROADS. 869 



Btruction was not begtin until September 9. The last concrete was deiK>sited 

 on October 5, and the project was entirely finished on October 20. 



The culvert Is in Maple Swamp, on the road from Dillon to Rethea's farm, 

 and the adjacent land is approximately level. The foundation, which is 

 natural soil, was excavated by hand, and the material was removed with wheel- 

 barrows. Sand was obtained from a pit and hauled 3 miles, while crushed 

 syenite was shippeil 112 miles by rail and hauled 1 mile in wagons. For the 

 abutments the concrete was mixed in the proportion 1:2.5:5. and for the floor 

 slab and parapets 1:2:4. The total amount of concrete in the structure is 32 

 cubic yards. The following were the principal items of cost : Temporary road, 

 $4.10; excavation for abutments, $14.68; excavation for outlet, $3.50; mixing 

 and placiug concrete, $10.23; hauling sand, $21.37; hauling stone from cars, 

 $15.25; lumber for forms, $23.05; building forms. $14; taking down forms, $2.95; 

 58 }-inch square-twisted steel bars, each 12 feet long, $19.06; 37 barrels of 

 cement, at $1.96 a barrel f. o. b. Dillon. $72.52; 37^ tons of broken stone, at 

 $1.88 a ton f. o. b. Dillon, $70.50; hardware and sundries, $8.03; rebate on 

 cement bags returned, $0.24 per barrel, $8.82. 



The total cost of the work was $278.22, or $8,693 jier cubic yard of concrete. 

 The costs per cubic yard of concrete for each of the several principal items 

 were as follows: Forms, $1.27; excavation, including that for outlet, $0,508; 

 mixing and placing concrete, $0,507; hauling sand from pit. $0,068; hauling 

 stone from cars, $0,476; steel bars, $0,614; cement f. o. b. Dillon, with rebate, 

 $1.99; stone f. o. b. Dillon, $2.23; hardware and sundries, $0.27. The cost per 

 hour for convict labor was figured at $0,025; for guards, $0.20; for teams with- 

 out drivers, $0.10; for teams with drivers, $0.30; and for carpenters. $0.30. 



A 16-foot span reinforced concrete culvert of the encased I-beam type was 

 also constructed at Dillon, S. C. The work of excavating the foundation was 

 begun on September 22, 1911, the first concrete laid on September 24, the con- 

 crete work finished on October 4. and the proje<'t entirely completed on October 

 17, 1911. This culvert is located on the Latta Road, which extends south from 

 Dillon toward I^tta, and the adjacent laud is approximately level. The founda- 

 tion was prepared by embedding a grillage of logs, spaced 2 feet, center to 

 center, well below the ground water line. The excavated material was handled 

 with shovels and removed in wheelbarrows. Sand, cement, and stone were 

 hauled in flat-bottom wagons of approximately one-half cubic yard capacity. 

 The aggregate consisted of crushed syenite and sand. The sand was hauled 3 

 miles in wagons from a local pit and the stone was shipped 112 miles by rail 

 and hauled 1 mile in wagons. The structure contains 54 cubic yards of con- 

 crete, all of which was mixed in the proportion 1 part Portland cement, 2 parts 

 sand, and 4 parts broken stone. 



The total cost was $534 ; the cost per cubic yard was therefore $9.89. The 

 following are the principal items of cost: Excavation, $17.40; grillage founda- 

 tion, $9.38; pumping, $3.75; mixing and placing concrete, $21.75; hauling sand, 

 $24.60; hauling stone from car, $22.00; miscellaneous, hauling cement, etc., 

 $6.87; building forms, $11.25; removing forms. $10.50; lumber for forms, $30; 

 62 tons of stone, at $1.S8 per ton, $110.50; 73i barrels of cement, at $l.n() i)er 

 barrel, $143.57; nine 12-inch 31i-pound steel I-beams, each 20 feet long, $110.85; 

 and 35 i-inch square-twisted steel rods, $10.50. The rebate on cement bags re- 

 turned anionnte<l to $17.58. The costs i)er cubic yard of concrete for the several 

 principal items were as follows: Excavation, $0..32; mixing and placing, $0,403; 

 forms, including cost of lumber, $1.07; hauling sand, $0,455; hauling stone, 

 $0,419; stone f. o. b. Dillon, $2.15; cement f. o. b. Dillon, with rebate deducted, 

 $2.33. The cost per hour for convict labor was figured at $0,025; for guards, 

 $0.20; and for teams with drivers, $0.30. The cost of superintendence was not 

 included. 



MODEL COUNTY ROAD SYSTEMS. 



IGNORE County, Ark. — At the request of Mr. R. B. Eggleston, deputy county 

 surveyor, an engineer from this oflice visited Tx^noke County in February, 1!)12, 

 and, after studying local conditions, made specific recommendations. It was 

 polntel out that considerable improvement conld be obtained in the treatment 

 of the "buck-shot" soil by decreasing (he width and raising the grade of the 

 roadbeds .-ibove the surrounding coniilry and .irrangiiig bolter dr.iinage. De- 

 tailed spoi'ifications were suppliiMl for the troatnient of the " bnck-shot " sub- 

 soil—with earth to produce an earth road which could be maintaincl by drag- 

 ging, with sand to produce a simd-clay road that would have a surface sujierior 



