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DocuSign Envelope ID:070B6BC7-CDE2-4AO8-BE62-07FA6BFDO53B <br /> 11/20/2020 <br /> 1. When air temperature has fallen to or is expected to fall below 40 deg F, uniformly heat <br /> water and aggregates before mixing to obtain a concrete mixture temperature of not less <br /> than 50 deg Fand not more than 80 deg Fat point of placement. <br /> 2. Do not use frozen materials or materials containing ice or snow. <br /> 3. Do not use calcium chloride, salt, or other materials containing antifreeze agents or <br /> chemical accelerators unless otherwise specified and approved in design mixtures. <br /> C. Hot-Weather Concrete Placement: Comply with ACI 301and as follows when hot-weather <br /> conditions exist: <br /> 1. Cool ingredients before mixing to maintain concrete temperature below 90 deg Fat time of <br /> placement. Chilled mixing water or chopped ice may be used to control temperature, <br /> provided water equivalent of ice is calculated in total amount of mixing water.Using liquid <br /> nitrogen to cool concrete is Contractor's option. <br /> 2. Cover steel reinforcement with water-soaked burlap, so steel temperature will not exceed <br /> ambient air temperature immediately before embedding in concrete. <br /> 3. Fog-spray forms, steel reinforcement, and subgrade just before placing concrete. Keep <br /> subgrade moisture uniform without standing water, soft spots,or dry areas. <br /> D. Pavement-Marking Paint: Proceed with pavement marking only on clean, dry surfaces and at a <br /> minimum ambient or surface temperature of 40 degrees F for oil-based materials, 55 degrees F <br /> for water-based materials, and not exceeding 95 degrees F <br /> PART 2 -PRODUCTS <br /> 2.1 CONCRETE, GENERAL <br /> A. ACI Publications: Comply with ACI 301unless otherwise indicated. <br /> 2.2 FORMS <br /> A. Form Materials: Plywood,metal,metal-framed plywood, or other approved panel-type materials <br /> to provide full-depth,continuous, straight, and smooth exposed surfaces. <br /> 1. Use flexible or uniformly curved forms for curves with a radius of 100 feet or less Do not <br /> use notched and bent forms. <br /> B. Form-Release Agent: Commercially formulated form-release agent that will not bond with, stain, <br /> or adversely affect concrete surfaces and that will not impair subsequent treatments of concrete <br /> surfaces. <br /> 2.3 STEEL REINFORCEMENT <br /> A. Plain-Steel Welded-Wire Reinforcement: ASTM A 1064/A 1064M, fabricated from as-drawn <br /> steel wire into flat sheets. <br /> B. Deformed-Steel Welded-Wire Reinforcement: ASTM A 1064/A 1064M, flat sheet. <br /> 32 13 13 CONCRETE PAVING Page 3 of 11 <br />