(A) Aggregate Base. On a prepared subgrade, with an approved density of 95% Dense Graded Aggregate meting Section 303 of the 1979 Kentucky Specifications for Road and Bridge Construction, or the most current amendment or amendments thereof unless such amendment or amendments shall require a lesser standard or specification to be applied in two courses. The D.G.A. shall be pugged and where the C.B.R. value of the subgrade is 4 to 7 shall be laid in 2-4 inch courses an where the C.B.R. value is 7 to 10 shall be laid in 2-3 inch courses. The D.G.A. base shall be placed and shaped to meet the required lines and cross-section of the typical section. (See drawing attached). The D.G.A. base shall be compacted to a density of no less than 84% of solid volume before any course of bituminous concrete is applied. The dense graded aggregate gradation shall be according to Section 805 (Table 1 - Coarse Aggregates) of the 1979 edition of the Kentucky Standard Specifications for Road and Bridge Construction, or the most current amendment or amendments thereof unless such amendment or amendments require a lesser standard or specification.
(B) Bituminous Base. On the dense graded aggregate base a 2 inch bituminous base course shall be applied. The bituminous base course shall be prepared and applied according to Section 401 of the Kentucky Standard Specifications for Road and Bridge Construction 1979 edition, or the most current amendment or amendments thereof unless such amendment or amendments shall require a lesser standard or specification. The gradation of the aggregate in the bituminous base course shall be:
% Passing | |
1 1/2" Sieve | 100% |
1" Sieve | 85-100% |
3/4" Sieve | ------ |
1/2" Sieve | 50-80% |
3/8" Sieve | ------ |
#4 Sieve | 30-50% |
#8 Sieve | 25-45% |
#16 Sieve | 15-35% |
#50 Sieve | 5-20% |
#100 Sieve | 3-10% |
Asphalt Content 4%-6%
1" Bituminous Surface Course - After the application of an approved tack coat at the rate of .1 gal/sq. yd. the bituminous surface source meeting the following gradation specification shall be applied:
% Passing | |
1/2" Sieve | 100% |
3/8" Sieve | 80-100% |
#4 Sieve | 55-80% |
#8 Sieve | 35-60% |
#16 Sieve | 22-46% |
#50 Sieve | 5-21% |
#100 Sieve | 3-14% |
#200 Sieve | 2-7% |
5.4" to 6% Asphalt AC-20 shall be used in the preparation of the bituminous surface mix.
(Ord. 1990-3, passed 6-11-90)