405.04 Method of Measurement.
The Engineer will limit the length of product placement ahead of the asphalt spreader (usually no more than 1000 feet) to reduce the possibility of damage. The Engineer will also require the placement of Pavon™ far enough ahead of the asphalt spreader to allow the curing of the product.
e.Curing Tack coat materials shall be fully cured before application of the overlying asphalt pavement layer is placed. Emulsified asphalt materials are considered as cured when the emulsion color has completely turned black. The NTSS -1HM asphalt emulsion shall be covered as soon as practical. Tack coat material shall be spread only far enough in advance to permit the construction to progress consistently, uniformly, and continuously after the curing period and shall not be applied so far in advance that the viscous quality will be reduced by traffic prior to construction thereon. Tack coat that loses its viscous quality before being covered shall be renewed and any which has been damaged shall be replaced without extra compensation.
405.04 Method of Measurement.
The amount of bituminous material used as directed for tack coat will be measured in gallons {liters}, as specified in Article 109.02. If Crafco or Pavon products are used, the Contractor shall provide a suitable means of measurement of the gallons of product used.
405.05 Basis of Payment.
a.Unit Price Coverage . The amount of bituminous material used as directed for tack coat, measured as noted abo ve, will be paid for at the contract unit price bid per gallon {liter} which shall be full compensation for furnishing the bituminous material, hauling, heating, application, curing, and maintaining and for all equipment, tools, labor, and incidentals nece ssary to complete the work.
b.Payment will be made under Item No .: 405-A Tack Coat - per gallon {liter} PLANING (MILLING) OF EXISTING PAVEMENT
408.01 Description.
This Section shall cover the work of rem oving existing asphalt pavement by either planing or micro - milling. Micro -milling is required to provide a more uniform surface than can be achieved by planing.
408.02 Equipment.
The planing and micro -milling machines shall be: • Self-propelled; • Of a size and shape that allows traffic to pass safely through areas adjacent to the work; • Equipped with automatic grade and cross slope controls; • Equipped with a means to prevent du st from escaping the milling operation; • Capable of maintai ning the required depth of cut and cross slope; • Furnished with a lighting system for night work if night work is required or allowed by the engineer; • Provided with conveyors capable of removing the milled material and emptying it directly into trucks to be hauled away from the roadway. Micro -milling equipment shall be capable of removing pavement to an accuracy of 1/16 of an inch.
408.03 Construction Requirements.
a.Pavement Removal . The existing pavement shall be removed to varying depths in a manner which will restore the pavement surface to a uniform longitudinal profile and cross section as shown on the plans or as directed by the Engineer. The approximate depths of required removal are shown on the plans. The depth of removal shall be increa sed or decreased across the width of the pavement to obtain the required roadway cross slope. The Contractor may make multiple cuts to achieve the required depth of cut.
408.04 Method of Measurement.
The pavement removal shall be done to effectively minimize the amount of airborne dust . Wetting of the pavement may be required to minimize the airborne dust. The Contractor shall provide a means of drainage to prevent water accumulation on the surface where the pavement has been removed. Unless otherwise noted on the plans, the pavement r emoval shall be limited to an area that will be covered with a surface treatment or a layer of pavement within the time shown below: • For planing, within seven calendar days after removal has begun. • For micro -milling, within 30 calendar days after remov al has begun. The Contractor shall collect, transport and dispose the removed pavement material. The removed material shall become the property of the Contractor unless otherwise noted on the plans. After pavement removal and immediately prior to resurfaci ng or opening to traffic, the surface shall be thoroughly swept with a power broom to remove fine material and dust particles. Sweeping shall be conducted in a manner that will minimize the potential for creation of a traffic hazard and minimize the creati on of airborne dust. Material removed by sweeping shall be collected, transported and disposed by the Contractor.
b.Final Planed Surface . The final planed surface shall be a uniform finish on the grade and slope shown to be required on the plans. The fin ished surface shall also not vary more than 1/4 of an inch from a 10 foot straightedge placed anywhere on the surface of the milled area. The Contractor shall make adjustments to the planing equipment if these surface tolerances are exceeded.
c.Test Sec tion for Micro -Milling . Micro -milling shall be performed on a test section prior to beginning the micro -milling work. The size of the test section shall be the width of the micro -milling machine and a length of 1000 feet {300 m}. The difference between the ridge and valley of the milled surface shall not exceed 1/16 of an inch when measured anywhere on the surface of the milled area. Production micro -milling shall not begin until the Engineer approves the results of the micro -milling of a test section. The Contractor shall make adjustments to the micro -milling equipment and micro -mill another 1000 foot {300 m} long test section for evaluation by the Engineer until an acceptable test section has been produced. The Contractor will not be allowed to start pro duction micro -milling until an acceptable test section has been produced. Repeated test sections shall be located in areas that have not been milled. If the surface of the micro -milling is determined to be unacceptable at any time after production begins , the Engineer will require the Contractor make adjustments to the equipment and produce another test section for evaluation and approval. Payment will not be made for micro -milling test sections that are unacceptable. Payment will be made after adjustmen ts have been made and the surface of the test section is milled to an acceptable finish.
d.Final Micro -Milled Surface . The final micro -milled surface shall be a uniform finish on the grade and slope shown to be required on the plans. The finished surface shall also not vary more than 1/4 of an inch from a 10 foot straightedge placed anywhere on the surface of the milled area. The difference between the ridge and valley of the milled surface shall not exceed 1/16 of an inch. The Contractor shall make adju stments to the micro -milling equipment and construct a test section for evaluation and approval if these surface tolerances are exceeded.
408.04 Method of Measurement.
The planing of pavement will be measured in square yards {square meters} computed from surface measurements taken to the nearest 0.1 of a foot {0.1 m} on the planed pavement. The micro -milling of pavement will be measured in square yards computed from surface measurements taken to the nearest 0.1 of a foot {0.1 m} on the micro -milled pavemen t. In areas where a non -uniform layer of thickness is removed, the approximate layer thickness will be computed by averaging the depth of cut at opposite lane edges for each travelway at longitudinal measurement intervals of approximately 300 feet {100 m} or as directed by the Engineer. This average depth will be used to establish the item number under which payment will be made.
408.05 Basis of Payment.
408.05 Basis of Payment.
a.Unit Price Coverage . The planing and micro -milling of pavement will be paid for at the contract unit price which shall be full compensation for removing the pavement, collecting, transporting and disposing of the removed pavement and other debris, the removal and disposal of pavement markers, sweeping the pavement and collecting, transportin g and disposing of the swept debris and for all materials, equipment, tools, labor, and incidentals necessary to complete the work. .
b.Payment will be made under Item No .: 408-A Planing Existing Pavement (Approximately * inches {mm} thru ** inches {mm} thick) - per square yard {square meter} 408-B Micro -Milling Existing Pavement (Approximately * inches thru ** inches thick) - per square yard * Lower limit of approximate thickness to be removed. ** Upper limit of approximate thickn ess to be removed. SECTION 409 TRIPLE LAYER BITUMINOUS SURFACE TREATMENT
409.01 Description .
This Section covers the materials, equipment, construction, and application procedures for placing three applications of bituminous materials and aggregate for surfacing previously prepared bases or existing paved surfaces. Bituminous materials shall be p laced within the tolerance specified, unless otherwise ordered by the Engineer in writing. Any variation outside of the designated limits shall be cause for ordering the treatment to be removed and replaced or corrected as directed by the Engineer, all wit hout additional cost to the Department. The rate of aggregate coverage shown by the table is the approximate rate found to produce an acceptable coverage when properly applied. Regardless of the rate shown, the Contractor shall provide aggregate in sufficient quantities and so spread the aggregate that the bitumen is uniformly and evenly covered. The Engineer will notify the Contractor in writing should it become advisable to change the amounts of any material from the limits specified in the table. In such event an adjustment in the contract unit price will be made as specified in Subarticle 409.06(a).
409.02 Materials.
All materials shall comply with the requirements of Division 800, Materials, except as noted herein. Special reference is made to the follo wing:
a.Bituminous Materials. Sources for bituminous materials surface treatments shall meet the requirements given in Article 804.01. The Contractor shall have the option of the following material for the triple layer surface treatment: • CRS-2p • CRS-2hp • CRS-2l CRS-2p, CRS -2hp, and CRS -2l shall meet the specific requirements given in Article 804.04 and Subarticle 804.07(e).
b.Aggregate. Coarse aggregates for bituminous surface treatments shall be crushed aggregate meeting the requirements of Section 801 and Section 802. The kind of aggregate materials used shall be at the Contractor's option within the following limits:
1.The use of carbonate stone such as limestone, dolomite, or aggregate tending to polish under traffic shall be restricted a s follows, based on the average daily traffic (ADT) count in both directions: ≤ 500 vehicles per day - No restrictions apply.
Source: Alabama Standard Specifications for Highway Construction, 2022 Edition. Pages 201–202 of 934.