§ 11-127. Special subbase.

(a)

Unless waived in writing by the County Road Superintendent, a special subbase shall be placed under all rigid pavements. The minimum thickness of the special subbase shall be two (2) inches unless the County Road Superintendent specifies a thicker depth. But in no case should the depth exceed four (4) inches.

(b)

The special subbase shall be one (1) of the materials listed below.

(1)

Coarse limestone screenings meeting the following gradation:

Screen Size	Percent Retained
½″	0
#4	24— 35
#10	78— 88
#20	92—100
#40	94—100
#200	96—100

 

(2)

Surface treatment aggregate meeting the AHTD Standard Specification requirements for Class 10 Mineral aggregate.

(3)

Any other well draining material approved by the County Road Superintendent.

(4)

If necessary, the special subbase shall be rolled with a light steel roller, but a specific density will not be required.

(Ord. No. 91-9, Art. 1, § 4.08, 4-11-91; Ord. No. 99-32, Art. 1, 7-8-99)