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9/2/2020 <br /> <br />32 13 13 CONCRETE PAVING Page 3 of 12 <br />B. Cold-Weather Concrete Placement: Protect concrete work from physical damage or reduced <br />strength that could be caused by frost, freezing, or low temperatures. Comply with ACI 306.1 and <br />the following: <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 />DocuSign Envelope ID: 7D9ACD4F-8F6C-42B6-9ADB-C60032DB6D03