SECTION 413
SECTION 413 -- HOT-POURED CRACK SEALANT
Description
1.1 This work shall consist of filling the major cracks in the pavement with an approved sealant material. The cracks to be filled
will be those designated by the Engineer.
Materials & Equipment
2.1 Material shal! be of the hot-poured type and be a product as included on the Qualified Products List.
2.1.1 Material not covered by an asphalt pavement overlay shall meet the requirements of ASTM D6690 Type II.
2.1.2 Material covered by an asphalt pavement overlay shall be low modulus conforming to ASTM D6690 Type IV except
cone penetration shall be 110-150,
2.2 Equipment shall meet the approval of the Engineer and shall be maintained in good working condition at all times.
{a) Air compressors shail be portable and capable of furnishing not less than 100 ft of air per minute at not less than 90 psi
pressure at the nozzle. The compressor shall be equipped with traps that maintain the compressed air free from oil and
water. Filters shall be inspected daily to ensure that they are still effective and not saturated with oil and moisture.
Saturated and/or damaged filters shall be replaced.
(b) Melting kettles shall be of the double-boiler, indirect-fired, portable type. The kettle shall be mounted on rubber tires and
shall be equipped with a metal shield beneath the firebox to protect the pavement. The space between the inner and outer
shells shall be filled with a suitable heat transfer oi] or substitute having a flash point of not less than 530°F. The kettle
shall be equipped with a satisfactory means for agitating the joint sealer to maintain a uniform temperature. This may be
accomplished by continuous stirring with mechanically operated paddles or by a continuous circulating gear pump
attached to the heating unit, or by both paddles and a pump. Kettles equipped with rocking type agitation shall not be
used. The kettle shall be equipped with a thermostatic control calibrated between 200° and 550°F.
(c) Hand pouring pots shall be equipped with mobile carriages and rubber shoes and have flow control valves that allow all
cracks to be filled to refusal.
(d) Routers for reshaping cracks shall be of the multiblade rotary cutter head type.
(ce) Hot-air lances for blowing clean and drying cracks shall be an approved propane gas burner and compressed air device
that does not allow the flame to touch the pavement.
(f) The wand applicator shall be connected to the holding tank through an applicator hose that ensures the safety of the
operator and allows the operator to control the flow of material. A device shall be mounted to bypass material into the
holding tank if the applicator nozzle is shut off.
Construction Requirements
3.1 All cracks greater than 1/8” up to 3/4” in width shall be shaped with a power router to a dimension of 3/4” +1/8” wide by
5/8” deep rectangular shape and treated unless otherwise directed. Cracks greater than 3/4” shall be treated but not routed. Router
bits will be maintained to ensure that rectangular dimensions are achieved. A rounded shape will not be allowed.
3.2 All cracks ordered treated shall be hot-air lance cleaned of dirt, foreign material, and loose edges.
3.3 The material removed from the cracks shall be removed from the roadway surface prior to reopening the roadway to traffic.
3.4 The hot-poured sealant shall be maintained in the kettle and applied at the temperature range specified by the manufacturer.
The Contractor shall furnish the Engineer with copies of the manufacturer’s literature indicating the application temperature range.
3.5 The hot-poured sealant shall be applied to the cracks using hand pouring pots or wand applicators within 2 minutes following
hot-air lance cleaning. Only wand applicators shall be used for crack filling when cracks are not covered by an asphalt pavement
overlay.
3.6 All cracks to be treated shall be filled to 1/16” to 1/8” below the pavement surface with hot-poured sealant with the sealant
left slightly concave. Filling flush, overfilling, and overbanding of cracks will not be allowed. Sealant shall tightly bond to the
pavement, The sealant bond to the pavement shall be checked after it has sufficiently cooled. If the sealant does not bond to the
pavement, sealant shall be removed and crack sealing operations discontinued until debonding problem is corrected.
3.7 No hot-air lance cleaning or crack sealing shall be performed when the pavement and cracks are wet or the ambient
temperature is below 50°F.
3.8 All work shall be performed in a neat manner. The sealant shall be allowed to cool sufficiently to prevent lifting, sticking,
and tracking prior to returning the pavement segment to traffic.
3.9 The contents of the kettle shall be emptied at the end of each day and shall not be reused.
2016 NHDOT
GoTo=)> TOC Division 100 Division 200 Division 300 Division 400 Standard
Division 300 Division 600 Division 700 Specifications
