1963 825 Ordinance - Laserfiche WebLink

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sha.11 be transported to the site of vrork in portable type mixers mounted on mot~~:° trucks. The mixing device shall be operated so as to revolve at the r ate o.f.' 1':.~~~_'. ttivelve to twenty-four revolutions per minute.. Those shall be no segregation o' the mixed concrete vrhen it is delivered on the site of ~rrork, and cone^ete s}.~:.11 be mixed riot to exceed one hour before.: placing, unless otllerz~rise pex~nitted. by the Engineer, (d) PROPORT TOTdS : Concrete shall consist of a mixture of Air-Entraining Pertlancl Cement, coarse aggregate., sand and ~~ra.ter, proportioned in accordance ~~ritll tl~e requirements of this specification. Cement shall be measured by v,~eight and shall be vreigl~ed on a balance or sc~~..1e separate from those used to v.~eigh the other ingredients. ~:.ggrega.tes s.iall be measured by vreight. Batch v~~eights shall be baser.I on surf?.ce dried ~nateri~~.ls acid shall be correctec? to to}{e into account the weyght of surface vratcr con-;a.ined in the aggregates. ~i~7ater shall be mea.surec. '.o~ volume or v,~ight, Total or maxi- mum tivater shall be considered as that including' addecl :^~ter and absorbed (surface) water in aggregates. Concrete shall be C1a.ss "D" -Ohio Staterii4;h;°ray Sioecifications and shall be proportioned as follozfvs I:.~initnum cement, bags per 1 cu. yd. of concrete 6-1/2 lelaximtun ~~r~.ter, €al7_oris per bag of cer_~Zent 5-1/2 Y~;iinimum compressive ^trength., lb. per sq. i~:. a.t 28 days 3,500 Proportion by volume, cement to total a~~;reg:te 1 to 5-1/~ Slanp range in inches (A,S.T.I~:. Designation C 1~3) 2 - 3 The weights in pounds of dry aggregates pel° sacl~ (9~;.lbs.) o_e air-entrain- ing por-tland cement shall be as follovrs Fine Aggregate 180 lbs. Coarse Aggregate 300 lbs. Total I~80 lbs. T.he vres.gl_~ts. used in the above table of aggregates a:~ e based on specific Yravities of ?_.65 for. sand a.nd limestone. (e) F'ORi~S: Contractor must use steel .form, for bo~tll str^ight a.nd radial vrork, znrith full division plates every fLve feet a.nd v;~ th dropped forms at all pro- posecl or existing clrivevra~ra to allovr a four inch dror from. the curb grade. All forms must be clean and coated. ti~rith a suitable oil before the placing of con- crete. The loans must be secvse7_J 'pr~~ced and held to e~.act line and grade of the street. The space to be filled vri•th concrete must be free f.~°oi1 all rubbish or debris a.t the time the concrete is placed. Concrete sha17. be thoroug}:1.y mixed before being deposited in clean steel forms adequately braced to prevent distor- tion from the specified dimensions. The concrete shall be thoroughly rarimed or vibrated. (.f) PLACING: The concrete shall be placed in the fo cribed, in 1a~rers thin enou~_h to permit thorough s}~a. SUCK a ma.il:ner as to eliminate all voids. The top of such a. manner as to thorougY~1- compact the concrete surface. The addition of c:rt3°a morta:c, in order to be permitted. The edge of the curb shall be beveled radius by use of a tool. especially designed for tY•iis must also be similarly dressed and +,,he exposed face vrith a. vrood float immediately alter removing tl-ie fo in place for such length of time that the removal of or otherwise ipjure the concrete. rms, prepared as above des- d.:ing. Tt shall 'oe spa.ded in the curb shall be coated irz and produce a smooth and even secure -i;}~is result, ~~rill not to a bullnose of 1-1/2" purpose. 'edges of the joints of the curb shall be rubbed r?ns. Curb forir~s shall be loft same does not crac}~, shatter C-3