Laserfiche WebLink
1 The mix design will be the initial JMF for the class of HMA. The Contractor may request a <br /> 2 change in the JMF. Any adjustments to the JMF will require the approval of the Engineer <br /> 3 and may be made in accordance with this section. <br /> 4 <br /> 5 HMA Tolerances and Adjustments <br /> 6 1. Job Mix Formula Tolerances — The constituents of the mixture at the time of <br /> 7 acceptance shall be within tolerance. The tolerance limits will be established as <br /> 8 follows: <br /> 9 For Asphalt Binder and Air Voids (Va), the acceptance limits are determined <br /> 10 by adding the tolerances below to the approved JMF values. These values <br /> 11 will also be the Upper Specification Limit (USL) and Lower Specification Limit <br /> 12 (LSL) required in Section 1-06.2(2)D2 <br /> Property Non-Statistical Evaluation Commercial Evaluation <br /> Asphalt Binder +/-0.5% +/-0.7% <br /> Air Voids, Va 2.5% min. and 5.5% max N/A <br /> 13 For Aggregates in the mixture: <br /> 14 a. First, determine preliminary upper and lower acceptance limits by applying the <br /> 15 following tolerances to the approved JMF. <br /> Aggregate Percent Non-Statistical Commercial <br /> Passing Evaluation Evaluation <br /> 1", 3/" '/2", and 3/8"sieves +/-6% +/-8% <br /> No.4 sieve +/-6% +/-8% <br /> No. 8 Sieve +/-6% +/-8% <br /> No. 200 sieve +/-2.0% +/-3.0% <br /> 16 b. Second, adjust the preliminary upper and lower acceptance limits determined <br /> 17 from step (a) the minimum amount necessary so that none of the aggregate <br /> 18 properties are outside the control points in Section 9-03.8(6). The resulting <br /> 19 values will be the upper and lower acceptance limits for aggregates, as well as <br /> 20 the USL and LSL required in Section 1-06.2(2)D2. <br /> 21 2. Job Mix Formula Adjustments—An adjustment to the aggregate gradation or <br /> 22 asphalt binder content of the JMF requires approval of the Engineer. Adjustments <br /> 23 to the JMF will only be considered if the change produces material of equal or <br /> 24 better quality and may require the development of a new mix design if the <br /> 25 adjustment exceeds the amounts listed below. <br /> 26 a. Aggregates —2 percent for the aggregate passing the 11/2", 1", 3/4", 1/2", %", and <br /> 27 the No. 4 sieves, 1 percent for aggregate passing the No. 8 sieve, and 0.5 <br /> 28 percent for the aggregate passing the No. 200 sieve. The adjusted JMF shall <br /> 29 be within the range of the control points in Section 9-03.8(6). <br /> 30 b. Asphalt Binder Content—The Engineer may order or approve changes to <br /> 31 asphalt binder content. The maximum adjustment from the approved mix <br /> 32 design for the asphalt binder content shall be 0.3 percent <br /> 33 <br /> 34 5-04.3(9)A Vacant <br /> 35 <br /> 36 5-04.3(9)B Vacant <br /> 37 <br /> 38 5-04.3(9)C Mixture Acceptance — Nonstatistical Evaluation <br /> 39 HMA mixture which is accepted by Nonstatistical Evaluation will be evaluated by the <br /> 40 Contracting Agency by dividing the HMA tonnage into lots. <br /> 2023 PAVEMENT MAINTENANCE OVERLAY <br /> WO#3789 February 14,2023 54 <br />