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<br />B. Preparation for placing <br />1. Water shall be removed from excavations before concrete is <br />deposited. <br />2. Any flow . of water shall be diverted through a proper side drain anti <br />shell be removed by methods which will avoid washing over the <br />freshly deposited concrete. <br />3. Hardened concrete, wood chips, shavings and other debris shall be <br />removed from the interior of the forms, and all hardened concrete <br />and foreign materials shall be removed from the inner surfaces of the <br />mixing and conveying equipment. <br />4. Forms shall be wetted, oiled or treated with an approved form- <br />coating materiel prior to placing concrete. <br />5. Reinforcement shall be cleaned, secured in position, inspected and <br />approved by the Engineer before starting the pouring of concrete. <br />6. Runways, or other means approved by the Engineer, shall be provided <br />for wheeled equipment to convey the concrete to the points of <br />deposit. The equipment used to deposit concrete shall not be wheeled • <br />over the reinforcement, nor shall the runways be supported on <br />reinforcement. <br />3.02 Installation <br />A. General <br />1. Concrete shall be conveyed from the mixer to the forms as rapidly as <br />practicable by a method which will prevent segregation or loss of <br />ingredients. <br />2. Concrete that has attained its initial set, or has contained its water <br />content for more than 1-1/2 hours shall not be deposited in the work <br />unless the concrete mix contains a set retarding admixture as <br />described herein. The retarding agent shall be a Type B or Type D <br />admixture as defined in AASHTO M194 (ASTM C-494). The agent <br />shall be free of calcium chloride. The air-entraining agent and the <br />retarding agent shall be so incorporated that the air content of the <br />concrete shall fall within the range specified. The Contractor shall <br />incorporate the retarding agent in water solution and the water so <br />included shall be calculated as effective mix water. Set retarding <br />admixtures shall be one of the following or an approved equal. <br />PROTARD - by Protex Industries <br />PDA-25R - by Protex Industries • <br />PDA-25 - by Protex Industries <br />Pozzolity 300R - by Master Builders <br />An approved equal <br />03300-fi <br />