510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS 2026 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS CATEGORY 500 PAVING SECTION 510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS
510.01 Description
Clean and seal cracks with a width between a minimum of 1/8 in. and a maximum of 1 in. Use asphalt repair mastic for cracks equal to or greater than 1 in. Cracks less than 1/8 in. wide do not need to be sealed. Repair distressed areas as specified, unless otherwise directed.
510.03 Construction
510.03.01 Equipment. All equipment shall be subject to approval. Ensure all equipment is
maintained in satisfactory working condition at all times.
a.Air Compressor. Air compressors shall be portable and capable of furnishing a minimum of 100 cubic feet of air per minute (cfm) and a minimum blast flow of 150 cfm. The compressor shall have a maximum of a 3/4 in. (20mm) diameter nozzle and shall be equipped with oil-free compressed air.
b.Hot Air Lance. The compressed air Hot Air Lance shall produce a minimum temperature of 750 F (400 C) at a minimum velocity of 650 ft/s. The compressed air must be produced from an air-compressor capable of producing a minimum of 125 cfm (0.06 m3/s) of clean, oil-free compressed air. The Hot Air Lance shall be designed such that the flame does not come in contact with the pavement.
c.Melting Kettle. The Melting Kettle shall be a self-contained double boiler that is capable of heating the sealant using oil as a heat transfer medium. The kettle shall be equipped with an automatic heat-control unit set capable of achieving a predetermined sealant temperature and maintain that temperature as long as required. The kettle shall be capable of safely heating the material to 400 F. The temperature control unit should not allow the heat transfer oil to exceed 525 F. The unit shall be capable of reading the temperature of the sealant within the melting vessel and within the discharge plumbing to provide monitoring and reporting of the sealant throughout the operation. The kettle 510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS 2026 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS shall also have an agitation system capable of continuously mixing the sealant to uniformly maintain the temperature within the manufacturer’s recommendations. The kettle must also be capable of applying the sealant to the pavement under pressure supplied by a gear pump with a direct connecting applicator tip. Do not use direct-fired kettles.
d.Hand Tools. Hand tools such as brooms, shovels, metal bars with chisel shaped ends, tamping equipment, and other miscellaneous tools required to accomplish the work.
e.Squeegee. Metal industrial type no more than 2-1/2 in. wide used to shape the surficial sealant material into a feather-edge band.
f.Crack Router. The crack router shall be capable of following random cracks and be designed to adjust cutting widths. The router width shall touch both sides of the crack for proper cutting. The router shall remove 1/8 in. from each side of the crack and cut back to sound pavement.
g.Mastic Mixer. The Mastic Mixer shall be thermostatically controlled and capable of heating the mastic mixture using oil as a heat transfer medium. The Mastic mixer must be equipped with a full sweep horizontal agitator capable of gently lifting the material from the bottom of the reservoir and mixing the material thoroughly. The agitator shall be capable of mixing and suspending materials filled with aggregates with a specific gravity as high as 3.0.
510.03.02 Quality Control Plan. Submit a Quality Control Plan (QCP) for approval at least
30 days prior to the placement of any crack sealer or asphalt repair mastic. The Plan shall document the proposed methods for controlling the equipment, materials, production, and operations to ensure conformance. The Plan shall also contain a list of technicians working on the project, their qualifications, and a list of all equipment to be used on the project. Discuss the Plan requirements with the Administration prior to construction.
510.03.03 Training. Technicians working on the project must take a mandatory online course
from National Highway Institute (NHI), Course No. FHWA-NHI-131110C - Pavement Preservation Treatment Series: Crack Sealing & Filling, and Joint Sealing. The course is provided free of cost. An unofficial transcript of successful completion of the course can be downloaded from NHI’s website. Submit transcripts with the QCP.
510.03.04 Crack Identification.
a.Wheel Path. Wheel path is defined as a distance of 16 in. to 56 in. (width of 40 in.) from the left or right of the center line of the roadway travel lane.
b.Cracks that can be effectively treated with crack sealants or mastic.
1.Transverse Thermal Cracks. These cracks extend across the pavement at approximately right angles to the pavement centerline or direction of lay-down. 510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS 2026 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS They are caused by shrinkage of the AC surface due to low temperatures or hardening of the asphalt and/or daily temperature cycling. These cracks are not load associated.
2.Transverse Reflective Cracks. These cracks extend across the pavement at approximately right angles to the pavement centerline or direction of lay-down. They are caused by cracking beneath the surface course, including cracks in PCC slabs.
3.Longitudinal Reflective Cracks. These cracks are parallel to the pavement’s centerline or laydown direction. They may be caused by shrinkage of the AC surface to low temperatures or hardening of the asphalt and/or daily temperature cycling, or a reflective crack caused by cracking beneath the surface course, including cracks in PCC slabs.
4.Longitudinal Cold Joint Cracks. They are caused by a poorly constructed paving lane joint or joint location. These joints are generally the least dense areas of a pavement and when constructed on the wheel path, a frequently loaded area, the joint fails prematurely.
c.Cracks that do not require crack sealing or asphalt repair mastic.
1.Alligator Cracking. These cracks are a series of interconnected cracks caused by fatigue failure of the asphalt concrete surface under repeated traffic loading. Cracking begins at the bottom of the asphalt surface where tensile stress and strain are highest under a wheel load. The cracks propagate to the surface initially as a series of parallel longitudinal cracks. After repeated traffic loading, the cracks connect, forming many-sided, sharp-angled pieces that develop a pattern resembling chicken wire or the skin of an alligator. The pieces are generally less than 2 ft on the longest side.
2.Edge Cracking. These cracks are parallel to and usually within 1 ft to 2 ft of the outer edge of the pavement. This distress is accelerated by traffic loading and can be caused by frost weakened base or subgrade near the edge of the pavement.
3.Slippage Cracks. These are crescent or half-moon shaped cracks having two ends pointing away from the direction of traffic. They are produced when breaking or turning wheels cause the pavement surface to slide or deform.
4.Longitudinal Cracks within the Wheel Path (defined under 510.03.04(a)).
510.03.05 Crack Sealing. Using the description in 510.03.04, identify cracks 1/8 in. to 1 in. wide
at the pavement surface, including reflective cracks, as directed. Exclude all longitudinal cracks within the wheel path areas. 510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS 2026 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS
510.03.06 Asphalt Repair Mastic. Identify cracks of at least 1 in. width, small potholes,
dislodged RPMS, and other vertically uneven roadway elements as directed. The minimum application depth for mastic should be 3/8 in.
510.03.07 Cleaning and Preparation.
510.03.07 01 Crack Sealing (No Routing).
a.Cleaning. All surfaces shall be dry and free of all dirt, dust, grease, and loose material prior to application of the filler. The cracks shall be cleaned by the use of compressed air produced from an air-compressor. The use of portable handheld or backpack blowers is not allowed. Direct the compressed air cleaning away from the passing traffic and do not blow debris into an already cleaned crack. Alternative methods of cleaning are subject to review and approval.
b.Drying. Dry the crack using a hot air lance prior to filler placement. The use of direct flame dryers is not permitted. Do not overheat pavement surfaces.
510.03.07 02 Crack Sealing with Routing.
a.Crack Routing. Perform routing of cracks to form a reservoir with a cut centered in the crack, touching each side of the crack, with a resulting width ranging from 0.5 in. to 1 in., depending on the width of the crack. The depth shall be 3/4 in. Perform routing in such a way that the pavement does not spall, thus allowing for optimal adhesion of the sealant to the crack edges. The reservoir should be square or U-shaped, not worn to a V- shape.
b.Cleaning. Refer to 510.03.07.01(a).
c.Drying. Refer to 510.03.07.01(b).
510.03.07 03 Asphalt Repair Mastic.
a.Cleaning. Refer to 510.03.07.01(a).
b.Drying. Refer to 510.03.07.01(b).
c.Primer. Apply a surface conditioner or primer when recommended by the mastic manufacturer to the surfaces prior to placement of the asphalt repair mastic. Apply in accordance with manufacturer’s recommendations to promote increased surface adhesion to the existing pavement. The surface conditioner or primer must thoroughly cover all surface areas where the asphalt repair mastic will be placed. Do not install the asphalt repair mastic until the surface conditioner or primer has sufficiently cured per recommendations. 510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS 2026 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS
510.03.08 Installation.
510.03.08 01 Crack Sealing.
a.Weather Restrictions. Perform crack filling when the ambient and pavement surface temperatures are between 30 F and 80 F, unless otherwise recommended by the manufacturer and as approved. Do not place sealant material if the pavement is wet. Should the sealant be placed and any precipitation occurs before the sealant has properly cured, remove and replace the moisture-affected sealant at no additional cost.
b.Application Temperature. Prior to installation of the crack sealant, the sealant shall be brought to application temperature recommended by the manufacturer.
c.Installation. Two methods can be used for crack sealing. The crack shall be sealed using the flush fill method with a squeegee finish or by placing an overband. The width of the overband should not extend more than 2 in. and should be no more than 1/20 in. thick, or the thickness of a dime. Keep sealant narrow and tight to the pavement to minimize snowplow damage. Perform material handling and installation in accordance with the manufacturer’s instructions.
d.Traffic Restrictions. Apply the manufacturer's recommended blotter material to minimize tracking and remove excess material before opening to traffic. The material should have cooled and solidified sufficiently to open to traffic.
e.Acceptance. Sealant that pulls loose within 96 hours after opening the pavement to traffic shall be repaired at no additional cost.
510.03.08 02 Asphalt Repair Mastic.
a.Weather Restrictions. Refer to 510.03.08.01(a).
b.Application Temperature. The minimum application temperature shall be according to the manufacturer’s recommendations. The maximum application temperature shall be 410 F, or according to the manufacturer’s recommendations.
c.Installation. The installer must be trained and approved by the mastic manufacturer.
1.Heat the Asphalt Repair Mastic using the Mastic Mixer. Place the heated mastic onto the properly prepared pavement, in layers if necessary.
2.Use a heated hand squeegee to level and smooth the mastic until the material has formed a durable, well-bonded, level repair. Keep the heated hand squeegee free of material buildup to ensure a smooth, quality finished product. 510 — SEALING CRACKS AND JOINTS IN ASPHALT PAVEMENTS 2026 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS
3.Apply the mastic according to the manufacturer’s instructions to the surface area from the bottom up in lifts appropriate to the specific application. Due to the depths of some of the repair locations, multiple lifts may be required to obtain a level surface. In the event that multiple lifts are required, allow each lift to be properly cooled before any subsequent lifts are applied on top. The final lift shall fill the uppermost 0.5 in. to 1 in. of the work area. Remove and dispose of all excess material from the roadway.
510.04 Measurement and Payment
Payment will be full compensation for furnishing, hauling, and placing of all materials, crack routing, crack sealing, asphalt repair mastic treatment, the removal and disposal of old filler and debris, and for all material, labor, equipment, tools, and incidentals necessary to complete the work. Payment will not be made for wasted material.
510.04.01 Crack Sealer without Routing will be measured and paid for at the Contract unit price
per linear foot, per lane mile, or per pound as specified.
510.04.02 Crack Sealer with Routing will be measured and paid for at the Contract unit price per
linear foot, per lane mile, or per pound as specified.
510.04.03 Asphalt Repair Mastic will be measured and paid for at the Contract unit price per
gallon.
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Source: Standard Specifications for Construction and Materials, 2026 Edition. Pages 677–682 of 1,138. View official source ↗