PART 1 - GENERAL

1.01 SECTION INCLUDES - Emulsified Asphalt Slurry Seal

1.02 DESCRIPTION OF WORK

A. Includes the requirements for surface treatment of an existing pavement with an application of an emulsified asphalt slurry seal.

1.03 SUBMITTALS

A. Submit under provisions of Division 1.

B. Material Submittal: Upon request the contractor will provide Material Certifications to the Jurisdictional Engineer along with proposed mix design.

1.04 SUBSTITUTIONS

A. Use only materials conforming to these specifications unless permitted otherwise by the Jurisdictional Engineer.

B. Obtain approval of Jurisdictional Engineer for all substitutions prior to use.

1.05 DELIVERY, STORAGE AND HANDLING:

The various aggregate products used shall be kept separate, and adequate provisions shall be made to prevent intermingling. Stockpiling and processing shall be handled in a manner that will ensure uniform incorporation of the aggregate into the mix.

1.06 SCHEDULING AND CONFLICTS

A. Construction Sequence:

1. Attend a preconstruction meeting if required by the Jurisdictional Engineer.

2. Submit plan for construction sequence and schedule prior to commencing construction

B. Traffic Control Plan: The Contractor shall develop a traffic control plan based on the Manual on Uniform Traffic Control Devices (MUTCD). Traffic control plans that are provided in the contract documents shall be reviewed by the Contractor and all traffic control devices used shall be in accordance with the MUTCD.

C. The Contractor shall Conform to Local, State and Federal Requirements.

1.07 RESTRICTIONS ON OPERATIONS

A. Wet / Night Conditions: Slurry seal shall not be placed when rain is predicted or on a surface with visible free water in front of the slurry machine. However, the pavement surface should always be kept damp. The mixture shall not be applied if high relative humidity prolongs the curing beyond a reasonable time. Slurry seal shall not be applied during night conditions.

B. Surface Temperature Restrictions: The mixture may be applied if both the pavement and air temperature are above 50^o F and rising.

1.08 MEASUREMENT FOR PAYMENT

The slurry seal shall be measured and paid by the square yards of work computed, and accepted in place by the Jurisdictional Engineer or authorized representative.

PART 2 - MATERIALS AND EQUIPMENT

2.01 MATERIALS

A. Asphalt Emulsion: The emulsified asphalt shall conform to the requirement of ASTM D 2397 Specification, for type cationic CSSlh or anionic SS1h emulsion.

B. Aggregate: The mineral aggregate shall consist of natural or manufactured sand, slag, crusher fines, and others, or a combination thereof. Smooth-textured sand shall not exceed 50 percent of the total combined aggregate. The aggregate shall be clean and free from vegetable matter and other deleterious substances. When tested according to ASSHTO 96, the aggregate shall show a loss of not more than 40.

Mineral fillers such as Portland cement, limestone dust, fly ash, and others shall be considered as part of the blended aggregate and shall be used in minimum required amounts. Fillers shall only be used if needed to improve the workability of the mix or gradation of the aggregate.

C. Mixture Gradation: Crushed aggregate and mineral filler shall be combined to obtain a mixture that meets the following gradations for the type of slurry seal specified in the contract documents or by the Jurisdictional Engineer.

Sieve Size	Percent Passing Sieve
	Type 1	Type 2	Type 3
3/8 in	100	100	100
No. 4	100	90-100	70-90
No. 8	90-100	65-90	45-70
No. 16	65-90	45-70	28-50
No. 30	40-65	30-50	19-34
No. 50	25-42	18-30	12-25
No. 100	15-30	10-21	7-18
No. 200	10-20	5-15	5-15

D. Water: All water used in the slurry mixture shall be potable and free of harmful soluble salts.

2.02 COMPOSITION OF THE SLURRY MIX:

A. The amount of asphalt emulsion to be blended with the aggregate shall be as specified in the contract documents and as adjusted in the field.

B. A minimum amount of water may be added as necessary to obtain a fluid and homogeneous mixture. The mixture shall be of a consistency such that it “rolls” in the spreader box in a continuous mass.

C. Slurry that segregates in the spreader box, so that flowing of liquids (water and emulsion) is evident, is not acceptable and shall not be applied.

2.03 EQUIPMENT:

A. The slurry mixing machine continuous flow mixing unit, capable of delivering a predetermined proportion of aggregate, water, and asphalt emulsion to the mixing chamber and discharging the thoroughly mixed product on a continuous basis. The equipment shall be capable of prewetting the aggregate immediately prior to mixing with the emulsion. The mixing unit shall be capable of thoroughly blending all materials together.

B. Whenever mineral filler is required for the mixture, the mixing machine shall be equipped with an approved fines feeder that includes an accurate metering device or method to introduce a predetermined proportion of mineral filler into the mixer. The mineral filler shall be fed into the mixer at the same time and location as the aggregate.

C. The mixing machine shall be equipped with a water pressure system and fog type spray bar, adequate for complete fogging of the surface receiving slurry treatment.

D. A mechanical type squeegee distributor with flexible material in contact with the surface of the pavement to prevent loss of slurry from the distributor shall be connected to the mixing machine. It shall be maintained so as to prevent loss of slurry on varying grades and crown. There shall be a steering device and flexible strike off. The spreader box shall have an adjustable width and shall be capable of placing the slurry mixture to the width specified in the contract documents.

E. Cleaning equipment in the form of power brooms, power blowers, air compressors, water flushing equipment, and hand tools shall be provided to clean the surface and cracks as required prior to slurry sealing operations