411.01 Description. This item shall consist of an asphalt
concrete cold plant mix, composed of a mixture of m ineral aggregate and asphalt, according to these specifica tions.
411.02 Materials. The asphalt concrete cold plant mix shall be
furnished from sources listed on the Department’s Q ualified Products List. Materials used in the mix shall con form to the following:
a.Asphalt. The Engineer will specify the type and grade of asphalt to be used. The asphalt shall be an MC-250, MC-800, MC-3000, a, or an inverted emulsion type asphalt. Medium curing asphalt shall comply with the require ments of Subsection 403.03. 293 Inverted emulsion type asphalt shall comply with th e following requirements: Inverted Emulsions Characteristics Minimum Maximum -Flash Point, Tag Open Cup °F 200 - -Viscosity (SF), sec at 140 °F 100 - (AASHTO T 59) -Stone Coating A Coating, % 90 - Asphalt Run-off, % - 0 -Test on Residue from Distillation 500 °F (AASHTO T59) Residue by Distillation, % by Mass 80 - Oil distillate, % by Volume 2 - -Test on Residue from Cutback Distillation (AASHTO T 78) Absolute Viscosity, P (AASHTO T 202) 30 800 Solubility, % (AASHTO T44) 97.5 - A-Stone Coating Test (at 140 °F) Weigh 200 grams of dry aggregate (at the gradation of the mix design) into a beaker. Weigh 4 grams of distilled water into the beaker co ntaining the dry aggregate and mix for 30 seconds. Dose dry aggregate with inverted emulsion at optimu m AC% and add to the beaker containing the damp aggregate and mix vigorously for 120 seconds. Dump contents in beaker onto a metal pan or suitabl e surface and visually check coating of aggregate. There sha ll be no evidence of asphalt run-off.
b.Mineral Aggregate. Mineral aggregate shall conform to the requirements of Section 409.
411.03 Mix Design. The Contractor shall furnish a mix design
performed by an asphalt design laboratory shown on the Department’s QPL. The design will be performed in accordance with Section 404, AHTD Test Method 470 and the requ irements of Table 411-1. 294 TABLE 411-1 DESIGN REQUIREMENTS FOR ASPHALT CONCRETE COLD PLANT MIX MAXIMUM MIX SIEVE, mm PERCENT PASSING TOLERANCE (%) ½″ (12.5) 100 #4 (4.75) 60-80 ±7 #8 (2.36) 43-63 ±5 #50 (0.300) 15-28 ±4 #200 (0.075) 4-10 ±2 Asphalt Binder Content 3.5%-6.5% ±0.4
411.04 Production Methods. The methods used in producing
the mix and the equipment and plant machinery used shall be subject to the approval of the Engineer and shall conform, insofar as practicable, to the requirements of Section 409.
a.Preparation of Asphalt. Medium curing cut-back shall be heated to a temperature not exceeding 250° F (120° C). Seasonal type asphalt shall be heated to a temperature not e xceeding 175° F (80° C).
b.Preparation of Mineral Aggregate. The coarse and fine aggregate shall be dried and heated at the mixing p lant so that when delivered to the mixer, it shall be at as low a tem perature as is consistent with proper mixing and in no case shall exceed 250° F (120° C) when using a medium curing cut-back or 175 ° F (80° C) when using a seasonal type asphalt.
c.Preparation of Mixture. Mixture preparation shall conform to the applicable portions of Subsection 410.03.
411.05 Quality Control and Acceptance. (a) Quality
Control. All acceptance sampling and testing by the Contra ctor shall be performed in a qualified laboratory by a c ertified technician. Requirements for technician certification and labor atory qualification are contained in the Department’s Manual of Field Sampling and Testing Procedures. The Contractor shall perform all quality control sampling and testing in accordance with Subsection
404.04 except that the only properties determined s hall be for
gradation and asphalt content. Either one of the f ollowing two 295 methods shall be used for determination of gradatio n and asphalt content compliance: • Asphalt content determined by extraction tests (AHT D 450) and sieve analysis (AASHTO T 30) of the extracted aggregate; or • Asphalt content determined by a nuclear asphalt con tent gauge (AHTD 449/449A) and the sieve analysis (AASHT O T 30) of the aggregate sample obtained by washing ( AHTD 460). The Contractor shall provide an opportunity for the Engineer to observe all sampling and testing (including those f or acceptance), provide an opportunity to review all test results, and shall furnish a building with facilities for the use of the Departm ent’s inspector according to Subsection 409.03(h).
b.Acceptance. All acceptance sampling and testing by the Contractor shall be performed in a qualified labora tory by a certified technician. Requirements for technician certificat ion and laboratory qualification are contained in the Department’s Manual of Field Sampling and Testing Procedures . The accepted mix design shall be field verified by the Contractor at the start of mix production or after an interruption of more than 90 calendar days . Verification shall consist of test results showing that the valu es for gradation and asphalt content are within the tolerances shown on the mix design. Acceptance and adjustment will be in accordance wit h Subsection 410.09(a) except that there will be no s ublots and the standard lot size will be 750 tons (750 metric tons ). The Department will only perform verification testing as needed an d acceptance and adjustment will be based on the Contractor’s test r esults. All sampling and testing for acceptance and adjustment shall be performed using the test methods specified in Subse ction 411.05(a) for quality control sampling and testing. Acceptan ce will be based on the adherence to the gradation and asphalt conte nt tolerances as shown on job mix design. When the results of either the quality control or a cceptance tests indicate the mixture is outside the specified toler ances, further evaluation of the mixture will be made to determine its acceptability. 296 411.06 Construction Requirements. Construction methods in addition to the general requirements of these speci fications shall conform, insofar as applicable, to Section 410.
411.07 Method of Measurement. Asphalt Concrete Cold Plant
Mix will be measured by the ton (metric ton) of mix . When an automatic printer system is used in conjunc tion with an automatic batching and mixing control system, the p rinted batch weight will be used in lieu of truck scale weights.
411.08 Basis of Payment. Work completed and accepted and
measured as provided above, will be paid for at the unit price bid per ton (metric ton) for Asphalt Concrete Cold Plant Mi x, which price shall be full compensation for furnishing materials ; for heating and mixing; for furnishing acceptable mix designs; for performing quality control and acceptance sampling and testing ; for hauling, stockpiling, placing, rolling, and finishing, as ap plicable; and for all labor, equipment, tools, and incidentals necessary to complete the work. Payment will be made under: Pay Item Pay Unit Asphalt Concrete Cold Plant Mix Ton (Metric Ton)
Source: , Edition.