Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1
ITEM 404.11 - MICRO-SURFACING
A. SCOPE
Work shall include all labor, materials, equipment, and transportation required for surface
preparation and placement of a thin overlay (micro-surface) as shown on the plans and as
directed by the Engineer.
B. MATERIALS
Emulsified Asphalt
The emulsified asphalt shall be a quick-set, polymer-modified cationic type CSS-1H emulsion,
and shall conform to the requirements specified in AASHTO M208 and ASTM 2397. It shall
pass all applicable storage and settlement tests. The polymer shall be milled into the emulsion,
or in the case of the HiMA (6% SBS) emulsion, may be blended into the unmodified base
asphalt. The cement mixing test shall be waived for this emulsion.
Fiber-Reinforced Micro-Surfacing Residue Properties
For fiber-reinforced mixtures, emulsion testing by distillation method (ASTM D5 or AASHTO
T49) shall yield Penetration values of between 40 and 120 dmm at 77 degrees F, and a Softening
Point (ASTM D36 or AASHTO T53) not less than 135 degrees F.
HiMA (6% SBS) Micro-Surfacing Residue Properties
For HiMA mixtures, emulsion testing by distillation method (ASTM D5 or AASHTO T49) shall
yield a Softening Point (ASTM D36 or AASHTO T53) not less than 170 degrees F.
Aggregate
The mineral aggregate used shall be of the type and grade specified for micro-surfacing. The
aggregate shall be manufactured crushed stone such as granite, slag, limestone, chat, or other
high quality aggregate or combination thereof.
Aggregate Physical Requirements
Grading: The aggregate including natural fines when tested by AASHTO methods T11 or T27
or ASTM C117 or C136, should meet the referenced gradation requirements.
Deleterious Substances: To limit the permissible amount of clay-like fines in an aggregate, a
sand equivalency value of 65 or higher is required when tested by ASTM 2419.
Soundness: The aggregate shall have a weighted loss of not more than 15% when the sodium
sulfate test is used, or 20% when the magnesium sulfate test is used.
