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D. Use chutes which are steel or steel - lined, and which have a slope not <br />exceeding one vertical to two horizontal and not less than one vertical to <br />three horizontal. Chutes more than 20 feet long, and chutes not satisfying <br />slope requirements, may be used if the chutes discharge into a hopper, <br />designed to prevent segregation, before distribution. <br />1 E. Place concrete in forms using troughs, chutes or pipes with the end held not <br />more than three feet above the surface of the base form or the concrete. <br />Troughs, chutes or pipes shall have steel hoppers tops with sides sloping at <br />least 45 degrees. <br />F. Use bottom -drop buckets to place concrete wherever possible. Buckets <br />shall permit gradual release and shall have sides sloping at least 45 <br />degrees near discharge. <br />t <br />3.14 DEPOSITING: <br />07/06 <br />A. Deposit concrete into the forms as nearly as possible to its final position, to <br />eliminate segregation of aggregates. Do not use vibrators for extensive <br />shifting of the mass of fresh concrete. The free drop of concrete shall not <br />exceed three feet without the use of adjustable length pipes. Place column <br />concrete by means of pipes adjustable in length and not less than six <br />inches in diameter. <br />03300 -15 05 -5564 <br />E. <br />Compact subgrade smooth, remove debris and deleterious matter, then wet <br />before placing concrete. <br />F. <br />Do not place concrete until forms, reinforcement and embedded items have <br />been approved by Engineer. <br />3.13 CONVEYING: <br />' <br />A. <br />Handle concrete from the mixer to the place of final deposit as rapidly as <br />practicable by methods that will prevent segregation, undue drying to <br />temperature rise, or loss of ingredients, and in a manner that will maintain <br />the required quality of concrete. <br />B. <br />Use conveying equipment, of size and design to maintain a continuous flow <br />of concrete at the delivery end, acceptable to the Engineer. Do not use <br />' <br />conveying equipment with aluminum parts, such as chutes, hoppers, or <br />scrapers, that could come in contact with the concrete during conveying. <br />C. <br />Use belt <br />conveyors which are horizontal or at a slope which will cause <br />neither segregation nor loss. Use a baffle board or other arrangement at <br />the discharge end to prevent segregation. Discharge long runs into hopper <br />without segregation. Do not allow concrete to adhere to the return belt. <br />D. Use chutes which are steel or steel - lined, and which have a slope not <br />exceeding one vertical to two horizontal and not less than one vertical to <br />three horizontal. Chutes more than 20 feet long, and chutes not satisfying <br />slope requirements, may be used if the chutes discharge into a hopper, <br />designed to prevent segregation, before distribution. <br />1 E. Place concrete in forms using troughs, chutes or pipes with the end held not <br />more than three feet above the surface of the base form or the concrete. <br />Troughs, chutes or pipes shall have steel hoppers tops with sides sloping at <br />least 45 degrees. <br />F. Use bottom -drop buckets to place concrete wherever possible. Buckets <br />shall permit gradual release and shall have sides sloping at least 45 <br />degrees near discharge. <br />t <br />3.14 DEPOSITING: <br />07/06 <br />A. Deposit concrete into the forms as nearly as possible to its final position, to <br />eliminate segregation of aggregates. Do not use vibrators for extensive <br />shifting of the mass of fresh concrete. The free drop of concrete shall not <br />exceed three feet without the use of adjustable length pipes. Place column <br />concrete by means of pipes adjustable in length and not less than six <br />inches in diameter. <br />03300 -15 05 -5564 <br />