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2025 FEDERAL OVERLAY, BROADWAY – CALIFORNIA ST TO 18TH ST SPECIAL PROVISIONS <br />FEDERAL AID# STBGUL-2715(012); COE PW# 3841 SP-72 May 6, 2025 <br /> <br />5-04.3(3) Equipment 1 <br /> 2 <br />5-04.3(3)A Mixing Plant 3 <br />Plants used for the preparation of HMA shall conform to the following requirements: 4 <br /> 5 <br />1. Equipment for Preparation of Asphalt Binder – Tanks for the storage of 6 <br />asphalt binder shall be equipped to heat and hold the material at the required 7 <br />temperatures. The heating shall be accomplished by steam coils, electricity, or 8 <br />other approved means so that no flame shall be in contact with the storage tank. 9 <br />The circulating system for the asphalt binder shall be designed to ensure proper 10 <br />and continuous circulation during the operating period. A valve for the purpose of 11 <br />sampling the asphalt binder shall be placed in either the storage tank or in the 12 <br />supply line to the mixer. 13 <br /> 14 <br />2. Thermometric Equipment – An armored thermometer, capable of detecting 15 <br />temperature ranges expected in the HMA mix, shall be fixed in the asphalt binder 16 <br />feed line at a location near the charging valve at the mixer unit. The thermometer 17 <br />location shall be convenient and safe for access by Inspectors. The plant shall 18 <br />also be equipped with an approved dial-scale thermometer, a mercury actuated 19 <br />thermometer, an electric pyrometer, or another approved thermometric 20 <br />instrument placed at the discharge chute of the drier to automatically register or 21 <br />indicate the temperature of the heated aggregates. This device shall be in full 22 <br />view of the plant operator. 23 <br /> 24 <br />3. Heating of Asphalt Binder – The temperature of the asphalt binder shall not 25 <br />exceed the maximum recommended by the asphalt binder manufacturer nor shall 26 <br />it be below the minimum temperature required to maintain the asphalt binder in a 27 <br />homogeneous state. The asphalt binder shall be heated in a manner that will 28 <br />avoid local variations in heating. The heating method shall provide a continuous 29 <br />supply of asphalt binder to the mixer at a uniform average temperature with no 30 <br />individual variations exceeding 25°F. Also, when a WMA additive is included in 31 <br />the asphalt binder, the temperature of the asphalt binder shall not exceed the 32 <br />maximum recommended by the manufacturer of the WMA additive. 33 <br /> 34 <br />4. Sampling and Testing of Mineral Materials – The HMA plant shall be equipped 35 <br />with a mechanical sampler for the sampling of the mineral materials. The 36 <br />mechanical sampler shall meet the requirements of Section 1-05.6 for the 37 <br />crushing and screening operation. The Contractor shall provide for the setup and 38 <br />operation of the field-testing facilities of the Contracting Agency as provided for in 39 <br />Section 3-01.2(2). 40 <br /> 41 <br />5. Sampling HMA – The HMA plant shall provide for sampling HMA by one of the 42 <br />following methods: 43 <br /> 44 <br />a. A mechanical sampling device attached to the HMA plant. 45 <br /> 46 <br />b. Platforms or devices to enable sampling from the hauling vehicle without 47 <br />entering the hauling vehicle. 48