02741.RTF

SECTION 02741

DIVISION 2

CRACK SEALING

02741 - 1 H:\8348\8348003.23\Docs\B-3 Specs\Division 2\02741.RTF June 7, 2005

PART 1 GENERAL

1.1 DESCRIPTION:

The work consists of routing (if required), cleaning and sealing cracks in asphalt pavement, and cracks between asphalt pavement and concrete building aprons, gutters or slotted drains.

PART 2 PRODUCTS

2.1 CRACK SEALANT COMPOUND:

The crack sealant method shall be single component, hot applied elastically polymer modified asphalt or asphalt rubber component. The asphalt cement, granulated vulcanized rubber, virgin rubber, fillers and plasticizers. The sealant shall meet the following requirements:

TEST

TEST METHOD

REQUIREMENTS

Cone Penetration

ASTM D5329

10-25 Resilience

ASTM D5329

25% mm.

Softening Point

ASTM D36

220F mm.

Ductility, 77F

ASTM D113

20 cm. Mm.

Flow 140F

ASTM D5329

0 mm max Brookfield Viscosity, 400F

ASTM D2669

100 Poise max Asphalt Compatibility

ASTM D5329

Pass Safe Heating Temperature N/A 400F Recommended Pour Temperature N/A 380F

Each lot of sealant delivered to the job site shall be accompanied by the manufacturer’s certification stating that it meets the requirements of this specification.

PART 3 EXECUTION

3.1 WEATHER LIMITATIONS:

Sealant shall be applied only when the temperature of the pavement surface is 350F and rising, and the relative humidity is 50 percent or less. Sealant shall not be applied when the wind exceeds 12 MPH as reported by Tucson International Airport, or when blowing sand or dust is present. Sealant shall not be applied during rain or when the pavement surface or cracks are wet.

After crack sealing operations have been suspended due to windy conditions, the area to be sealed shall be cleaned by means of a Power Jet Vacuum Broom Sweeper before sealing work resumes.

3.2 CLEANING AND SEALING:

1. Immediately prior to applying the sealant, all cracks shall be thoroughly cleaned of all loose particles, dust and other deleterious substances by compressed air. The Contractor shall provide an air compressor capable of producing at least 125 CFM and line pressure of at least 125 PSI. All loose material shall be removed by means of Power Jet Vacuum Broom Sweeper.

2. Cracks shall be filled to within 1/8 inch of the pavement surface using the sealant specified in Materials 2.1. Cracks shall not be overfilled. The sealant shall not be placed during wet weather. The sealant shall be applied by nozzle so that the crack channel is filled from the bottom up and air is not trapped beneath the sealant.

3. If a backer rod is used, it should be placed to a depth that will provide a shape factor (depth to width ratio) of approximately 1. However, the maximum depth that the backer rod should be placed is approximately ¾ inch.

3.3 ASPHALT PAVEMENT CRACKS ¼ INCH TO ¾ INCH:

These cracks shall be routed in a manner that produces a uniform rectangular reservoir, conforming to the dimensions shown on the plans. The router shall be centered as neatly as practicable over the crack. The router shall have a bit that is wide enough to cover the size of the crack being routed. A backer rod material shall be placed in cracks that have a depth greater than ¾ inch.

3.4 ASPHALT PAVEMENT CRACKS ¾ INCH TO 2 INCH:

These cracks shall be cleaned as described in Construction Requirements 3.2 and 3.3, tacked and filled with asphalt concrete as specified under Section 02742.

3.5 ASPHALT PAVEMENT CRACKS GREATER THAN 2 INCH:

These cracks should be prepared in the same manner as potholes. A saw cut should be used to cut away damaged pavement to provide vertical faces. The area should then be cleaned and filled instead of sealed.

3.6 CRACKS BETWEEN CONCRETE AND ASPHALT PAVEMENT:

Cracks in the joints between asphalt pavement and concrete building aprons, gutters or slotted drains shall be cleaned and sealed as described under Construction Requirements 3.2. Routing is not required.

END OF SECTION 02741