366 The finished surface shall not vary more than 3/8 inch from the lower edge of a 10- foot straightedge, when the straightedge is placed both parallel and perpendicular to the centerline of the roadway. Humps or otherwise elevated areas shall be corrected by reworking, additional rolling, trimming, milling, or abrasive grinding. Depressions shall be correcte d by milling to sufficient depth and applying a tack coat of emulsified asphalt to accommodate a patch consisting of cold recycled material, or warm or hot mix asphalt, meeting the requirements of Engineer. 408- 11 Method of Measurement: The cold recycled material will be measured by the square yard, completed in place, and accepted by the Engineer. The engineered emulsion and mineral admixture(s) will be measured by the ton. 408- 12 Basis o f Payment: The accepted quantities of cold recycled material, measured as provided above, will be paid for at the contract unit price per square yard for the material complete in- place. Material meeting the requirements of Sections 409, 416, and/or 417 of the specifications, and placed in locations where cold recycled material was removed, will be paid for at the bid item price for Cold Recycling. The engineered emulsion measured as provided above will be paid for by the ton. The contract unit price for engineered emulsion will be adjusted for quantities of material represented by corresponding test results. Adjustments will be made in accordance with the requirements of Subsection 1005 -3.03 of the specifications. Mineral admixture will be paid for at the predetermined price established in the Bidding Schedule. SECTION 409 ASPHALTIC CONCRETE (MISCELLANEOUS STRUCTURAL) : 409- 1 Description: The work under this section shall consist of constructing Asphaltic Concrete (Miscellaneous Structural), hereinafter asphaltic concrete, by furnishing all materials, mixing at a plant, hauling and placing a mixture of aggregate materials, reclaimed asphalt pavement (RAP) if used, mineral admixture, and bituminous material (asphalt cement) to form a pavement course or to be used for other specified purposes, in TABLE OF CONTENTS INDEX 367 accordance with the details shown on the project plans and the requirements of the specifications, and as directed by the Engineer. The contractor shall acquire and make all arrangements for a source or sources of material, furnish a mix design which will meet the design criteria specified hereinafter, and provide all the equipment, materials, and labor necessary to complete the work. 409- 2 Materials: 409- 2.01 Mineral Aggregate: Mineral aggregate shall conform to the following requirements when tested in accordance with the applicable test methods. Mineral Aggregate Characteristics Test Method Requirement Combined Bulk Oven Dry Specific Gravity Arizona Test Method 251 2.350 - 2.850 Combined Water Absorption Arizona Test Method 251 0 - 2.5% Abrasion AASHTO T 96 100 Rev., Max 9% 500 Rev., Max 40% Sand Equivalent AASHTO T 176 (After thoroughly sieving the sample, no additional cleaning of the fines from the plus No. 4 material is required.) Minimum 55 Fractured Coarse Aggregate Particles Arizona Test Method 212 Minimum 70% (plus No. 4 material) Carbonates (1) Arizona Test Method 238 Maximum 20% Notes:
conditions exist:
subject to traffic for more than 60 days.
TABLE OF CONTENTS INDEX 368 The gradation will be determined in accordance with Arizona Test Method 201, and shall conform to the requirements given below. Mix Design Grading Limits Sieve Size Percent Passing Lift Thickness Less Than 1½ Inches Lift Thickness 1½ to 2 Inches Lift Thickness Greater Than 2 Inches Without Admixture With Admix ture Without Admixture With Admixture Without Admixture With Admixture 1 Inch 100 100 3/4 Inch 100 100 90-100 90-100 1/2 Inch 100 100 90-100 90-100 --- --- 3/8 Inch 90-100 90-100 70-85 70-85 70-85 70-85 No. 8 41-55 42-56 41-51 42-52 41-51 42-52 No. 40 9-19 10-20 --- --- --- --- No. 200 2.0-5.0 3.0-6.5 2.0-5.0 3.0-6.5 2.0-5.0 3.0-6.5
409- 2.02 Bituminous Material: Asphalt cement shall be a performance grade (PG) asphalt binder conforming to the requirements of Section 1005 of the specifications. The type of asphalt binder shall be as shown in the Special Provisions. The percent of asphalt cement used shall be based on the weight of total mix (asphalt cement, mineral aggregate, and mineral admixture). The contractor shall provide the laboratory mixing and compaction temperature ranges to the mix design laboratory for each PG asphalt binder used for mix design purposes. The laboratory mixing temperature range is defined as the range of temperatures where the un- aged asphalt binder has a rotational viscosity of 0.17 ± 0.02 Pascal·seconds, measured in accordance with AASHTO T 316. The laboratory compaction temperature range is defined as the range of temperatures where the un -aged asphalt binder has a rotational viscosity of 0.28 ± 0.03 Pascal·seconds, measure d in accordance with AASHTO T 316. The testing required in AASHTO T 316 shall be performed at 275 degrees F and 350 degrees F, and a viscosity- temperature curve developed in accordance with ASTM D2493. The viscosity- temperature curve shall be included in the mix design report. For PG asphalt binders that have a maximum laboratory mixing temperature exceeding 325 degrees F or a maximum laboratory compaction temperature exceeding 300 degrees F, the laboratory mixing and compaction temperature ranges shall be specified in writing by the asphalt binder supplier. The laboratory mixing and compaction temperature ranges, as well as the actual laboratory mixing and compaction temperatures used, shall be reported on the mix design. The contractor shall ensure that the asphalt binder supplier information required in this paragraph is provided to all appropriate parties in a timely manner, and that copies are included in the mix design report. The laboratory mixing and compaction temperatures are for mix design purposes only. Field mixing and compaction temperatures are specified in Subsection 409- 3 of the specifications. TABLE OF CONTENTS INDEX 369 409- 2.03 Mineral Admixture : Mineral admixture shall be either Portland cement, blended hydraulic cement, or hydrated lime conforming to the following requirements: Material Requirement Portland Cement, Type I or II ASTM C150 Blended Hydraulic Cement, Type IP ASTM C595 Hydrated Lime ASTM C1097
The mineral admixture content shall be 2.0 percent, by weight, of the mineral aggregate. However, a minimum of 1.0 percent mineral admixture may be used if the contractor submits test information showing a lowered percentage of mineral admixture produces mix design results for Index of Retained Strength of at least 60 percent and a Minimum Wet Strength of 150 pounds per square inch when tested in accordance with Arizona Test Method 802. The certification and acceptance of Portland cement, blended hydraulic cement, and hydrated lime shall be in accordance with ADOT Materials Practice and Procedure Directive No. 13, "Certification and Acceptance of Hydraulic Cement, Fly Ash, Natural Pozzolan, Silica Fume, and Lime". 409- 2.04 Mix Design: Utilizing mineral aggregate which has been crushed, processed, separated, and stockpiled, a mix design shall be formulated and submitted by the contractor to the Engineer. The mineral aggregate samples used for mix design purposes shall be representative of aggregate materials to be used during production. The mix design shall be based on the mix design criteria and other requirements specified herein, utilizing asphalt cement and mineral admixture of the type and from the sources proposed for use in the production of asphaltic concrete. The mix design shall be prepared by or under the direct supervision of a professional engineer experienced in the development of mix designs and mix design testing. Reclaimed asphalt pavement (RAP) may be used in the mixture if properly designed per Arizona Test Method 833; however, RAP will not be allowed in the mixture when asphalt cement type PG 76 22 TR+ or PG 70 22 TR+ is specified in Subsection 409 -2.02 of the specifications. Limits for the usage of RAP shall be per ADOT Materials Practice and Procedure Directive No. 20, “Guidance on the Use of Reclaimed Asphalt Pavement (RAP) in Asphaltic Concrete”. The mix design engineer shall meet the requirements given in ADOT Materials Practice and Procedure Directive No. 4, “Asphaltic Concrete Mix Design Proposals and Submittals”. The mix design shall be provided in a format that clearly indicates all the mix design requirements and shall be sealed, signed, and dated by the mix design engineer. TABLE OF CONTENTS INDEX 370 The mix design shall be prepared by a mix design laboratory that has met the requirements of ADOT Materials Practice and Procedure Directive No. 19, “ADOT System for the Evaluation of Testing Laboratories”. If approved by the Engineer, as an alternative to meeting the mix design requirements specified herein, a 1/2 inch or 3/4 inch mix design meeting the requirements of either Section 416 or Section 417 of the specifications may be substituted for use. The type of asphalt binder used in the alternative mix design must be the same as that specified in Subsection 409- 2.02 of the specifications. The alternative mix design may include reclaimed asphalt pavement (RAP) if properly designed per Arizona Test Method 833. The lift thickness for the alternative mix design shall conform to the following table. Alternative Mix Design Minimum Lift Thickness Section 416 (1/2 inch mix) 1-1/2 inches Section 416 (3/4 inch mix) 2 inches Section 417 (1/2 inch mix) 2 inches Section 417 (3/4 inch mix) 2-1/2 inches
The contractor may propose the use of a mix design that has been developed for a previous project. The proposed mix design shall meet the requirements of these specifications. The contractor shall provide evidence that the type and source of bituminous material, the type of mineral admixture, and the source and methods of producing mineral aggregate, and RAP material if applicable, have not changed since the formulation of the previous mix design. The contractor shall also provide current test results for all specified characteristics of the mineral aggregate, and RAP material if applicable, proposed for use. The Engineer will determine if the previously used mix design is suitable for the intended use and if the previous use of the mix design was satisfactory to the Department. The Engineer will either approve or disapprove the proposed mix design. Should the Engineer disapprove the use of the previously used mix design, the contractor shall prepare and submit a new mix design proposal in accordance with the requirements of these specifications. A previously used mix design older than two years from the date it was formulated, sealed, signed, and dated shall not be allowed for use. Once approved for use on a project, a previously used mix design may be used for the duration of that project. Test results used in the formulati on of the mix design must be from testing performed no earlier than 45 days prior to the date the mix design is signed by the mix design engineer. Historical abrasion values may be supplied on sources provided the testing was conducted within the past two years. The mix design shall be submitted to the Engineer under a cover letter signed by an authorized representative of the contractor. TABLE OF CONTENTS INDEX 371 The mix design shall be submitted to the Engineer for review a minimum of five working days prior to the start of production. The mix design shall meet the following criteria when tested in accordance with the requirements of the following test methods: Criteria Requirement Arizona Test Method 1.Voids in Mineral Aggregate: %, Range 14.5 - 18.5 (See Note 1) 2.Effective Voids: %, Range 5.3 - 5.7 (See Note 1)
Note:
RAP, Arizona Test Method 833. The Engineer reserves the right to adjust the asphalt content during production from the mix design value without additional compensation to the contractor in order to obtain desirable effective voids. 409- 2.05 Sampling and Testing: Sampling and testing the materials and mixture for quality control purposes shall be the contractor's responsibility. The contractor shall perform sufficient t esting to assure that mineral aggregate and asphaltic concrete are produced which meet all specified requirements. The Engineer reserves the right to sample and test the materials and mixture when necessary to determine that they reasonably conform to the requirements specified herein. 409- 3 Construction Requirements: 409- 3.01 General: All courses of asphaltic concret e shall be compacted as required, smooth and true to the required lines, grades, and dimensions. The following smoothness requirements shall be met :
under this section of the specifications shall be tested and shall not vary by more than 1/8 inch from the lower edge of a 10-foot straightedge when it is placed in the longitudinal direction (including across transverse joints), and when it is placed in the transverse direction across longitudinal joints;
section of the specifications, other than the final lift, shall be tested and shall not vary by more than 1/4 inch from the lower edge of a 10- foot straightedge when it is placed in the TABLE OF CONTENTS INDEX 372 longitudinal direction (including across transverse joints), and when it is placed in the transverse direction across longitudinal joints; and
be corrected by the contractor, to the satisfaction of the Engineer. The asphaltic concrete hot plant shall conform to the requirements of Section 403 of the specifications. No fine material which has been collected in the dust collection system shall be returned to the mixture unless the collected fines are accurately and uniformly metered into the mixture. The temperature of asphaltic concrete or mineral aggregate upon discharge from the drier shall not exceed 325 degrees F, unless a higher temperature is recommended in writing by the asphalt binder supplier and approved by the Engineer. The moisture content of the asphaltic concrete immediately behind the paver shall not exceed 0.5 percent. The moisture content will be determined in accordance with the requirements of Arizona Test Method 406. Asphaltic concrete shall be placed only when the temperature of the surface on which the asphaltic concrete is to be placed is at least 65 degrees F. At any time, the Engineer may require that the work cease or that t he work day be reduced in the event that weather conditions, either existing or expected, are anticipated to have an adverse effect upon the asphaltic concrete. All wheels and tires of compactors shall be wetted with water, or if necessary soapy water, or a release agent in order to prevent the sticking of asphaltic concrete. All other equipment surfaces shall be treated when necessary with a release agent. Only release agents evaluated through NTPEP are acceptable for use. The results from NTPEP testin g, when tested in accordance with AASHTO TP 102, shall meet the following criteria: RELEASE AGENT TEST REQUIREMENT Asphalt Stripping Test Diluted Non -Diluted (Full Strength) No Stripping No Stripping Mixture Slide Test 10 g Retained, Max. Asphalt Performance Test Less than or equal to 10.0% after the third cycle TABLE OF CONTENTS INDEX 373 Release agents which degrade, dissolve, or in any way damage the bituminous material shall not be used. Diesel fuel shall not be used as a release agent. Asphaltic concrete immediately behind the laydown machine shall be in a thoroughly mixed, free -flowing, and workable condition, be free of lumps and crusts, and have a minimum temperature of 275 degrees F. All courses of asphaltic concrete shall be placed and finished by means of self -propelled paving machines except under cer tain conditions or at certain locations where the Engineer deems the use of self -propelled paving machines impractical. The speed of the paving machine shall be coordinated with the production of the plant and an adequate number of trucks for hauling asphaltic concrete shall be available in order to achieve, as far as practical, a continuous operation. Self -propelled paving machines shall spread the mixture within the specified tolerances, without segregation or tearing, true to the line, grade, and crown i ndicated on the project plans. Pavers shall be equipped with hoppers and augers which will distribute the mixture uniformly in front of adjustable screeds. Pavers shall be equipped with a screed for the full width being paved, heated if necessary, and capable of spreading and finishing all courses of asphaltic concrete. Pavers shall be equipped with automatic screed controls with sensors for either or both sides of the paver, capable of sensing grade from an outside reference line, sensing the transverse slope of the screed, and providing the automatic signals which operate the screed to maintain the desired grade and transverse slope. Failure of the control system to function properly shall be cause for the suspension of the placing of asphaltic concrete. The base or subgrade upon which asphaltic concrete is to be placed shall be prepared and maintained in a firm condition until asphaltic concrete is placed. It shall not be frozen or excessively wet. Before asphaltic concrete is placed, the surface to be paved shall be cleaned of all objectionable material and tacked with bituminous material in accordance with the requirements of S ection 404 of the specifications. Longitudinal joints of each course shall be staggered a minimum of 1 foot with relation to the longitudinal joint of any immediate underlying course. Longitudinal joints shall be located within 1 foot of the center of a lane or within 1 foot of the center line between two adjacent lanes. TABLE OF CONTENTS INDEX 374 The contractor shall schedule its paving operations to minimize exposed longitudinal edges. Unless otherwise approved by the Engineer, the contractor shall limit the placement of asphaltic concrete courses, in advance of adjacent courses, to one shift of asphaltic concrete production. The contractor shall schedule its paving operations in such a manner to eliminate exposed longitudinal edges over weekends or holidays. 409- 3.02 Compaction: Compaction shall consist of an established sequence of coverage using specified types of compactors. A pass shall be defined as one movement of a compactor in eit her direction. Coverage shall be the number of passes as are necessary to cover the entire width being paved. The rolling sequence, the type of compactor to be used and the number of coverages required shall be as follows: Rolling Sequence Type of Compact or No. of Coverages Option No. 1 Option No. 2 Option No. 1 Option No. 2 Initial Static Steel Vibrating Steel 1 1 Intermediate Pneumatic Tired Vibrating Steel 2 - 6* 2 - 4* Finish Static Steel Static Steel 1 - 3 1 - 3 Note:
* Based on the roller pattern which exhibits the best performance. The Engineer shall select the option for compaction and, when pneumatic- tired compactors are used, will designate the tire pressure. Steel wheel compactors shall not be used in the vibratory mode for courses of 1 inch or less in nominal thickness nor when the temperature of the asphaltic concrete falls below 180 degrees F. Steel wheel compactors shall weigh not less than 8 tons. Initia l and intermediate compaction shall be completed before the temperature of the asphaltic concrete falls below 200 degrees F. All edges shall be rolled with a pneumatic tired compactor, or other methods approved by the Engineer, while the mixture is still hot. Compaction will be deemed to be acceptable on the condition that the asphaltic concrete is compacted using the type of compactors specified, ballasted and operated as specified and with the number of coverages of the compactors as specified. 409- 3.03 Acceptance: Asphaltic concrete will be accepted complete in place, if, in the judgment of the Engineer, the asphaltic concrete reasonably conforms to the TABLE OF CONTENTS INDEX 375 requirements specified herein. Asphaltic concrete that is not acceptable and is rejected shall be replaced to the satisfaction of the Engineer and at no expense to the Department. 409- 4 Method of Measurement: Asphaltic concrete will be measured by the ton for the mixture actually used, which will include the weight of mineral aggregate, bituminous material, and mineral admixture. Measurement will include any weight used in construction of intersections, turnouts, curbs, spillways and spillway inlets, ditches, catch basin entrances, median strips, sidewalks, or other miscellaneous items or surfaces. 409- 5 Basis of Payment: 409- 5.01 General: The accepted quantities of asphaltic concrete, measured as provided above, will be paid for at the contract unit price per ton for the bituminous mixture complete in place. No direct payment will be made for the bituminous material and mineral admixture in the asphaltic concrete, or the bituminous material for tack coat and application of tack coat, the price being considered as included in the price paid for asphaltic concrete. Asphaltic concrete may be measured, by volume, upon the execution of a supplemental agreement which will specify the manner in which the volume is determined. The volume will include the volume of mineral aggregate, bituminous material, mineral admixture, and any necessary blending material. 409- 5.02 Reduction for Noncompliance: A reduction in payment to the contractor for asphaltic concrete will be made for quantities of asphalt cement (bituminous material) that do not meet the requirements of Section 1005 as determined by corresponding test results. Adjustments in payment will be made in accordance with the requirements of Table 1005- 1 and the following formula: R=(100-P) x �(CP) x T 100� Where: R= Amount of reduction in payment (dollars) T= Quantity of asphalt cement in failure (tons, rounded to nearest 0.1) TABLE OF CONTENTS INDEX