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This Page Describes furnishing & applying a bituminous fog seal coat.

REFERENCED STANDARDS: ASTM (American Society for Testing and Materials)

GENERAL

SUBMITTALS

1. 1. Manufacturer’s specifications for vinyl acrylic copolymer for Port review and approval.
2. 2. Manufacturer’s certification that the material is the type, grade and quality specified; required for each load of bituminous material delivered. The certification shall show shipment number, refinery, consignee, destination, contract number and date of shipment.
3. 3. If requested supply two 1-gallon samples of diluted, ready-to-apply bituminous material for each load delivered.
4. 4. Submit sealant application plan for port approval prior to starting work. The plan shall address staging, traffic control, schedule, and pavement marking protection.

STORAGE AND HANDLING

Store and handle products in accordance with manufacturers recommendations.

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PRODUCTS

BITUMINOUS EMULSION CONCENTRATE

The emulsion concentrate, in the undiluted state shall have the following properties:

1. 1. Saybolt furol viscosity: 77° F, 20-100 seconds.
2. 2. Residue by distribution or by evaporation: 57 percent minimum.
3. 3. Sieve test: 0.2 percent minimum.
4. 4. pH, catatonic: 2 to 6.5.

The emulsion concentrate, when diluted in the proportion of one part of concentrate to one part of water, by volume and ready to apply, shall have the following properties:

1. 1. Saybolt furol viscosity: 77° F, 10-50 seconds.
2. 2. Residue by distribution or by evaporation: 28 to 42 percent, minimum.
3. 3. Sieve test: 0.1 percent, maximum.
4. 4. Pumping stability test: pass.

Tests on residue from Distillation or Evaporation:

1. 1. Viscosity ast 275°F, ASTM D-4402: 1750 cts max.
2. 2. Solubility in 1,1,1 trichloroethylene ASTM D-2042: 97.5 percent min.
3. 3. Penetration ASTM D-5: 50 dmm max.
4. 4. Asphaltenes ASTM D-2007: 15 percent min.
5. 5. Saturates ASTM D-2007: 15 percent max.
6. 6. Polar Compounds ASTM D-2007: 25 percent min.
7. 7. Aromatics ASTM D-2007: 15 percent min.

The bituminous base residue shall contain not less than 20 percent Gilsonite, and shall not contain any tall oil pitch. It shall be compatible with asphalt concrete and have a 5 year minimum, proven performance record at a commercial airport. (A commercial airport shall be defined as one utilized by aircraft which fall under FAA‘s Design Group 3- i.e., DHS Dash 8, Boeing 737 – and larger. Drying time, under recommended application conditions, shall not exceed 4 hours. Emulsion must be able to accept paint within 4 hours of application. Emulsion shall be GSB-88 Emulsion Sealcoat Concentrate as manufactured by Asphalt Systems, Inc. of Salt Lake City, Utah, or pre-bid approved equal.

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POLYMER

The vinyl acrylic copolymer shall be approved for use by the manufacturer of the Bituminous material for compatibility and shall have the following properties:

1. Solids content, percent by weight	....................................55 percent
2. Weight per gallon, lbs
Emulsion	..........................................9.0 lbs
Resin solids	..........................................9.8 lbs
3. pH	...............................................5.0
4. Viscosity, cps (as tested by the Brookfield RVT #3 spindle at 20 rpm and 25°C)	...........................................2250
5. Particle charge	......................................Nonionic
6. Free monomer, percent by weight	.........................05 percent, max.
7. Mechanical stability	.......................................Excellent
8. Minimum film forming temperature, °C	...............................................+5
9. Tg °C	...............................................+1

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SAND

The sand material shall consist of hard durable particles or fragments of granular aggregates or dry, clean, dust free slag with a Mohs hardness value of 7.5 – 8.0. Sanding material shall be black boiler sanding slag or similar angular, black abrasive. Tru-Grit as supplied by Kleen-Blast or pre-bid approved equal.

The material shall meet the following gradation analysis in accordance with ASTM D 451:

Sieve Size	.....................Percentage by Weight
No. 16.	.............................................0-0.1
No. 20	..............................................0-1
No. 30	..............................................5-20
No. 40	..............................................40-65
No. 50	..............................................20-40
No. 60	..............................................0-5
No. 100	.............................................0-3
Pan	.................................................0-0.2

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EXECUTION

INLAY STRIPING AND RETROREFLECTIVE MARKING PROTECTION

As specified prior to applying fog seal, cover and protect inlay striping and retro reflective markings. Inlays and retro reflective markings shall not have reduced visibility from fog seal spray. Lines and large pavement markings designated to be saved will be sealed to within 2 inches of the markings.

MIXING

A. The fog seal material shall be obtained by blending bituminous concentrate material, water and polymer. Mix one part bituminous emulsion concentrate to one part water, by volume. Water shall be a minimum of 120 degrees F.

B. Add 1 percent polymer, by total volume, to the mix. If the polymer is added to the mix at the plant, submit weigh scale tickets to the port. As an option, the polymer may be added to the mix at the job site provided the polymer is added while the circulating pump is running and the mix is agitated for a minimum of 15 minutes.

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WORK SITE PROTECTION

Place barricades around the perimeter of each area prior to starting work.

PAVEMENT PREPARATION

A. Prior to applying the fog seal, vacuum all accessible pavement surfaces with a drivable-air vacuum. Clean areas (i.e., around lights, signs, inlets, etc.) not accessible to the vacuum with a broom type sweeper, back pack blower or brooms.

B. Before applying the fog seal, cover existing fixtures and appurtenances including but not limited to, taxiway edge lights, centerline lights, in-pavement duct markers, retro-reflective film type pavement markings, drainage structures, and hold lines encountered within the fog seal limits. If the fog seal gets on any light, marker, hold line, or retro-reflective marking, clean immediately. If cleaning is not satisfactory to the port, replace any marking with equal material at no added cost to the port.

C. Before full fog seal is applied, pre-seal visible pavement joints with fog seal emulsion at the rate of 0.10 gallons per square yard, approximately 18-24 inches wide, and using no sand.

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EQUIPMENT

A. The emulsion may be applied with standard computerized bituminous distributors. The equipment shall be in good working order and contain no contaminants or diluents in the tank. Spreader bar tips shall be clean, free of burrs, and of a consistent size to maintain an even distribution of the fog seal material. Any type of tip or pressure source is suitable that will maintain a predetermined flow rate and constant pressure during the application process. Equipment shall maintain a constant flow through the nozzles during the application process regardless of the speed of the truck.

B. The equipment shall be capable of specific application rates in the range of 0.08 to 0.25 gallons per square yard. These rates shall be computer controlled rather than mechanical.

C. The distributor truck shall be equipped with a 14-foot, minimum spreader bar with individual nozzle control. Care s hall be taken not to over mix material.

D. The distributor shall be equipped to hand spray the seal coat around the edge lights, centerline lights, pavement markings, or other areas specified by the port.

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WEATHER LIMITATIONS

A. Do not apply the emulsion:

1. 1. To wet pavement surfaces
2. 2. During rainy or damp weather, or when rain is anticipated within 8 hours after application is completed.
3. 3. When the surface temperature is below 50°F.
4. 4. When wind speed exceeds 10 miles per hour.

B. Whenever possible, at least 3 hours of direct sunlight shall remain after completing application of the emulsion.

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APPLICATION

Apply the fog seal product using a manufacturer-approved applicator and in accordance with the manufacturer’s recommendations. Apply the emulsion only when the existing surface is clean and dry. Apply at the rate of not less than 0.13 to 0.18 gallons per square yard with a typical target rate of .15 gallons per square yards of diluted product. Use appropriate measures to prevent the fog-sealing product from running onto the grass or into the storm system. Any areas of excess application or pooling must be swept out by hand brooming.

On grooved runways the first 16 feet in form the shoulder may be applied at a rate of .10 gallons per square yard. Apply sealant to the balance of the runway as specified.

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SANDING

A.Sand immediately after application of the fog seal. The speed of the distributor shall be such that the sanding material shall be applied before the fog seal begins to break. Apply sand at the rate of 0.50 to 0.75 pounds per square yard as determined by the port.

B. Sanding shall be accomplished using a drop-type sander equipped with a full spread bar to ensure even distribution of the sand the entire length of the applicator. Tinkle or skip applicator bars will not be permitted. Spinner, chip seal or whirlybird type sanders will not be permitted. The sanding unit shall have the ability to apply sand in both the forward and backward direction to enable negotiating sand application onto areas where turning around is not possible. The sander shall have finite controls to regulate sand distribution. Manual-type hand sanders may be used around lights, signs, and other obstructions.

C. Schedule this work so the fog seal application and the sanding operation work as a cohesive unit. Sanding shall be done in a manner so as to prevent any sand from going onto the pavement prior to the fog seal being applied or to the adjacent pavement not sealed. The sanding application process shall not inhibit the effectiveness of groves on a grooved runway.

D. Clean up excess or loose sand with brooms, blowers or an air sweeper and dispose of off port property.

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AVAILABILITY AND COST

For further information on the availability and cost of emulsion, contact Asphalt Systems, Inc., P.O. Box 25511, Salt Lake City, Utah 84125-0511, (801) 972-2757, Fax (801) 972-6433 or pre-bid approved equal.

FREIGHT AND WEIGH BILLS

Before the final estimate is allowed, the Contractor shall provide the Owner certified weigh bills of the emulsion materials actually used in the construction covered by the contract. Copies of weigh bills shall be furnished to the Owner uring the progress of the work.

METHOD OF MEASUREMENT

The quantity of Emulsified Pavement Sealer and Rejuvenator to be paid for will be the number of square yards of material actually applied and accepted by the Owner as complying with the plans and specifications.

BASIS OF PAYMENT

Payment will be made at the contract unit price per square yard for Emulsified Pavement Sealer and Rejuvenator. This price will be full compensation for furnishing all materials, for all preparation, delivery, and application of these materials, and for all labor, equipment, tools, and incidentals necessary to complete this item, Including the furnishing, mixing of polymers, and the furnishing and placing of sand and any other work necessary to complete this item.

Payment will be made under:

Item P-609 Emulsified Pavement Sealer and Rejuvenator -- per square yard

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