EARTH, SAND-CLAY, AND GRAVEL ROADS. 
45 
surfaces, exclusive of grading, usually has ranged between $500 and 
$1,500 a mile. 
Table 8. — Cost of sand-clay roads, exclusive of grading and materials. 
Project number. 
Items. 
1 
2 
3 
4 
5 
6 
7 
8 
Brook- 
ville, 
Fla. 
Mos- 
cow, 
Miss. 
Pear- 
sail, 
Tex. 
San 
An- 
tonio, 
Tex. 
Gay 
Head, 
Mass. 
Jack- 
son, 
N. C. 
Tar- 
boro, 
N.C. 
Sayre, 
Okla. 
Length surfaced in miles 
0.45 
28 
20 
16 
660 
0.75 
3 
830 
0.50 
7 
$0. 175 
.50 
.031 
0.78 
30 
30 
17 
1,524 
1.5 
0.79 
26 
26 
15 
1.00 
40 
26 
16 
2.19 
22 
22 
16 
1,700 
0.125 
6 
2, 300 
0.10 
6 
$0.20 
.50 
.010 
f .223 
\ .344 
I .003 
.010 
.004 
.006 
0.45 
30 
30 
14 
2.50 
22 
22 
18 
0.75 
Width of graded road in feet: 
Cuts 
28 
Fills 
28 
Width surfacing (feet) 
14 
Sand mixture: 
Sand (cubic yards) 
1.00 
7 
890 
1.00 
Clay mixture: 
$0.10 
.25 
.003 
1,556 
0.19 
8 
$0.12 
.30 
.0064 
.091 
'".91%" 
.032 
.0017 
.0005 
.003 
1,825 
0. 057 
7 
$0. 15 
.34i 
.0088 
.072 
| .286 
.0069 
.0015 
2,815 
1,583 
1.42 
Depth applied in inches 
i 6 
$0,123? 'sin. 08 
8 
Scale of wages per hour: 
$0.16 
.35 
.002 
.029 
.84 
'""."077" 
'"'.'662' 
.003 
.24 
.0018 
.005 
.30 
Cost: 
Subgrade, per square yard 
Stripping for surfacing material, 
. 0096 
.134 
Hauling sand, per cubic vard 
.425 
.374 
.019 
.0035 
.0035 
.0157 
.49 
"~".~007~ 
.006 
Hauling clay, per cubic yard 
Spreading material, per cubic yard 
Mixing sand and clay, per square 
vard 
.255 
.0178 
.0024 
.0022 
.0007 
.567 
.072 
.007 
Final shaping, per square yard 
General expense, per square yard. 
Total cost, per square yard 
.198 
.105 
.121 
.089 
.082 
.233 
.036 
.187 
GRAVEL ROADS. 1 
Roads that are artificially surfaced with gravel, as denned on 
page 18, or with earthy material in the composition of which gravel 
predominates, are called gravel roads. This designation covers a 
variation in type which ranges from roads surfaced with a natural 
sand-clay mixture containing a considerable percentage of gravel to 
those having so-called " gravel macadam " surfaces, composed almost 
wholly of pebbles and constructed in practically the same manner 
as first-class macadam roads. Gravel roads constitute about one- 
third the total mileage of surfaced roads in the United States and 
are confined to no especial section of the country. 
In the following discussion of gravel roads it is convenient to con- 
sider the subject under the two general heads, " Selection of Gravel" 
and " Construction Methods." 
1 It is desired to acknowledge the assistance of W. H. Rhodes, U. S. highway engineer, 
In preparing this discussion, and of J. T. Voshell, J. D. Fauntleroy, J. A. Whitaker, and 
James C. Wonders, U. S. district engineers, in reading and revising the text. 
