4-1 DIVISIO N 400 SURFAC E COURSE S AND PAVEMENT SECTION 401 – AGGREGATE SURFACE COURSE
401.01 DESCRIPTION . This work shall consist of furnishing and placing a wearing course of approved
aggregate on a prepared surface.
401.02 MATERIALS . Materials shall meet the requirements of the following subsections:
Aggregate Surface Course ................................ ................................ ......................... 704.12(a) Aggregate Surface Cou rse, Paths and Trails ................................ .............................. 704.12( b)
401.03 PLACEMENT . The aggregate shall be placed and properly shaped using equipment that allows
the typical cross -section and design grade to be attained. Should aggregate segregation occur, the Contractor shall remove and replace the segregated material or manipulate it until uniform gradation is obtained. The minimum layer thickness for placement of any aggregate surface material shall be 2 inches after compaction, and the maximum layer thickness shall be 8 inches after co mpaction. All layers shall be placed and compacted at approximately equal thickness. In the placement of layers, all joints shall be staggered at least 12 inches. After each layer of surface material is placed, it shall be thoroughly compacted to a uniform density of not less than 95% of the maximum dry density as determined by AASHTO T 99, Method C , or to the satisfaction of the Engineer . Suitable and effective equipment, meeting the approval of the Engineer, shall be used to obtain a true and even surface during compaction. All holes or depressions found during the compacting shall be filled with additional material, reworked, and compacted. If required, water shall be uniformly applied over the aggregate material during compaction in an amount necessary t o produce proper consolidation. The aggregate shall be thoroughly compacted by an approved power roller with a minimum weight of 8 tons, by an approved rubber -tired roller, or by other approved methods.