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1 <br /> 2 5-04.3(3)A Mixing Plant <br /> 3 Plants used for the preparation of HMA shall conform to the following requirements: <br /> 4 <br /> 5 1. Equipment for Preparation of Asphalt Binder—Tanks for the storage of <br /> 6 asphalt binder shall be equipped to heat and hold the material at the required <br /> 7 temperatures. The heating shall be accomplished by steam coils, electricity, or <br /> 8 other approved means so that no flame shall be in contact with the storage tank. <br /> 9 The circulating system for the asphalt binder shall be designed to ensure proper <br /> 10 and continuous circulation during the operating period. A valve for the purpose of <br /> 11 sampling the asphalt binder shall be placed in either the storage tank or in the <br /> 12 supply line to the mixer. <br /> 13 2. Thermometric Equipment—An armored thermometer, capable of detecting <br /> 14 temperature ranges expected in the HMA mix, shall be fixed in the asphalt binder <br /> 15 feed line at a location near the charging valve at the mixer unit. The thermometer <br /> 16 location shall be convenient and safe for access by Inspectors. The plant shall <br /> 17 also be equipped with an approved dial-scale thermometer, a mercury actuated <br /> 18 thermometer, an electric pyrometer, or another approved thermometric <br /> 19 instrument placed at the discharge chute of the drier to automatically register or <br /> 20 indicate the temperature of the heated aggregates. This device shall be in full <br /> 21 view of the plant operator. <br /> 22 3. Heating of Asphalt Binder— The temperature of the asphalt binder shall not <br /> 23 exceed the maximum recommended by the asphalt binder manufacturer nor shall <br /> 24 it be below the minimum temperature required to maintain the asphalt binder in a <br /> 25 homogeneous state. The asphalt binder shall be heated in a manner that will <br /> 26 avoid local variations in heating. The heating method shall provide a continuous <br /> 27 supply of asphalt binder to the mixer at a uniform average temperature with no <br /> 28 individual variations exceeding 25°F. Also, when a WMA additive is included in <br /> 29 the asphalt binder, the temperature of the asphalt binder shall not exceed the <br /> 30 maximum recommended by the manufacturer of the WMA additive. <br /> 31 4. Sampling and Testing of Mineral Materials —The HMA plant shall be equipped <br /> 32 with a mechanical sampler for the sampling of the mineral materials. The <br /> 33 mechanical sampler shall meet the requirements of Section 1-05.6 for the <br /> 34 crushing and screening operation. The Contractor shall provide for the setup and <br /> 35 operation of the field testing facilities of the Contracting Agency as provided for in <br /> 36 Section 3-01.2(2). <br /> 37 5. Sampling HMA— The HMA plant shall provide for sampling HMA by one of the <br /> 38 following methods: <br /> 39 a. A mechanical sampling device attached to the HMA plant. <br /> 40 b. Platforms or devices to enable sampling from the hauling vehicle without <br /> 41 entering the hauling vehicle. <br /> 42 <br /> 43 5-04.3(3)B Hauling Equipment <br /> 44 Trucks used for hauling HMA shall have tight, clean, smooth metal beds and shall have a <br /> 45 cover of canvas or other suitable material of sufficient size to protect the mixture from <br /> 46 adverse weather. Whenever the weather conditions during the work shift include, or are <br /> 47 forecast to include, precipitation or an air temperature less than 45°F or when time from <br /> 2023 PAVEMENT MAINTENANCE OVERLAY <br /> WO#3789 February 14,2023 46 <br />