1957 566 Ordinance - Laserfiche WebLink

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_ f ~,.~ 'L shall be transported to the site of vrbrk in portable type mixers mour_ted an motor trucks. The mixing device shall be operated so as to revolve at the r ~ to of ":r•~_~~ t.~relve to t~,~renty-four revolutions per minute a, There shall be no segregation o~' the mixed concrete vrhen it is delivered on the site of ~rrork, and concrete shall be mixed not to exceed one hour before placing, unless otl~erlrise permitted by the Engineer. (d) PR.OPOP,T IU~iS : Concrete shall consist of a mi xture of Air-Entraining Portland Cement, coarse a.~;gregate, sand and vra~Eer, proportioned iri accordance z~ritli the renuirements of this specification. Cement shall be moasurod by vt~ei~;ht and shall be weighed on a balance or sc<^.le separate from those used to v~eigh the other ingredients. ~.ggrega.tes shall be measured by vreight. Hatch v~~eights. shall be based on surface dried rynaterfia:.ls a?ld shall be corrected to take .into a.cceunt the vre:ight of surface rrat~r cont~.ined in the aggregates. '~~;fater sha11 be measured by volume or v,~itht. Total or maxi- mum vrater shall be considered as that incl~.tding added Z~~ter and absorbed (surface) water in aggregates. Concrete shall be C1<:~.ss °D~~ -Ohio State I-iiUl~ivray Specifications and shall be proportioned as follovrs: ~initnutn cement, bags per 1 cu. ycl. of concrete 6-1/2 Iulaxi~n~~m ~~r~:.ter, gallons per bag of cer~~ent 5-J,i 2 Islinimtun compressive strength, lb. per s~.l. in. ~•t 28 days 3,500 Proportion by volume, cement to total ag~re~.~te 1 to 5-1/4. Slump range in incites (A,S.T.I~:I. Designation C l~3) ? - 3 Tlzc vreights in pounds of dr~r aggregates pe~° saclc (9?~. lbs.) of air-entrain- ing Portland cement shal.>_ be as follov~rs ; fine Aggregate 1~0 lbs. Coarse Aoregwte 300 lbs. Total ZG80 lbs. The 17ei.gl~its used in the above table of aggregates are based on specific gravities of 2.65 for sa_Yid a.nd limestone. (e) FOI-~~~S: Contractor must use steel form, for both. straight and radial vrork, ~~vith fu11 d7.vi sion elates every five feet a.nd ~;r th dropped forms at a_11 pro- posed or e=;fisting driveways to alloys a four. inch. drop from the curb grade. All forms must be clean and coated ~°rith a suitable oi.l before the placing of con- crete. The forms must be ssclzrely braced and held to enact line and grade of the street. The space to be filled tiri•th concrete must be free from all rubbish or debris a.t the time the concrete is placed. Concrete siZalJ_ be thoroug'r~ly mixed be_Fore being deposited in clean steel forms acle~uately braced to prevent distor- tion from the speci_#'iecl dimensions. The concrete sha11 be thoroughly rammed or vibrated. (f) PLACING: The concrete shall. be placed in the forms, prepared, as above des- cribed, in layers thin enough to permit ~thorougi~ sna.dn~;. Tt shall_ 'oe spaded in. such a manner as to eliminate all voids. The top of the curb sha11 be coated iri such a manner a.s to thoroughl~r comp~~ct the concrete axed produce a smooth and even surface. The addition of extra mortar, in order to secuz°e this result, i;*ill not lie permitted. The edge of the curb shall be beveled to a buLnose of 1.-1/2" radius by use of a tool especiall,,T designed for this purpose.. dges of the joints must also be similarly dressed and the exposed .face of the curb shall be rubbed with a wood float it;~unediately after removing the for?~s® Curb forms shalJ_ be left in place for such length of tune that tl~e removal of sane does not crack, shatter or othervrise injure the concrete. C-3