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removed by other approved methods which will avoid the washing of <br /> freshly deposited concrete. <br /> 10.3 PLACING METHODS <br /> Concrete shall be deposited continuously in horizontal layers in a manner <br /> that will prevent the displacing of reinforcement and the accumulation of <br /> concrete on the forms or reinforcement. <br /> 10.3.1 DROPPING CONCRETE <br /> The concrete shall not be allowed to drop freely more than four <br /> feet W). Drops greater than four feet (41 shall be accomplished <br /> by a confining device acceptable to the Engineer. <br /> 10.3.2 CHUTING <br /> Chuting of concrete shall be permitted only upon acceptance of <br /> the methods by the Engineer. Chutes shall be of rounded cross- <br /> section to avoid the accumulation of concrete in corners. The <br /> slope shall be steep enough to permit flow without requiring a <br /> slump greater than that specified or required for placement (slope <br /> usually one (1) vertical to two (2) or two and one-half (2%) <br /> horizontal). All chutes and hoppers shall be thoroughly cleaned <br /> before and after each run. All wash water and debris shall be <br /> discharged outside of forms. <br /> 10.3.3 PUMPING <br /> Where concrete is conveyed and placed by mechanically or <br /> pneumatically applied pressure, the equipment shall be suitable in <br /> kind and adequate in capacity for the work. The operation of the <br /> pump shall be such that a continuous stream of concrete without <br /> air pockets is produced. When pumping is completed, the <br /> concrete remaining in the pipeline shall be ejected in such a <br /> manner that there will be no contamination of the concrete in <br /> place. After this operation the entire equipment shall be thorough- <br /> ly cleaned. <br /> SPEC. B- CONCRETE <br /> PAGE 14 <br />