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24 hours in moist air, 175 lbs. .. ,..
<br />7 days (one day in air, 6 in vrater), 500.1bs.,
<br />28 days (one in air, 27 in water), 600 lbs.
<br />One part cement, three parts Standard sand. : ..
<br />7 days, (one day in air) ; 200 lbs.
<br />28 days (orie :e1ay in air, 27 in water), 275 lbs. . .
<br />' (b) 'I'he sand used shall be that required by seotion-87 hereof.
<br />( c) Aggregate. `i'he aggregate'- shall consist oi hard broken stone free
<br />frotn dust, clean gravel',,slag or sirnilar materia.l:.crushed; and screened to pass a
<br />one-inch ring and rejected on a 4 inch.ring. Both sand,,and aggregate shall be
<br />subject to the approval of the Tnspector. or" Buildinos,.vaho, may-demand that any,
<br />material in question be testecl- at the expense of tlie owner or owners in an, ap-.
<br />proval test test"irg lab'oratory and the certified::results submitted to the Ins-
<br />pector of Buildings to rzid in iorrn.ing an o:pinion as to the fitness or unfitness,
<br />of the material for the purposein tended: .
<br />Sec.144:. STEEL IN CONCREIE. All reinforcing steel not,rolled from bil-
<br />let shall be rolleet from-standard section- tee -rails and snall comply with the
<br />physical properties of concrete reinforcing bars.adopted by The gssociation of
<br />American Steel` Manufa:cturers; 19104 A complete physical test shall _ be niade by
<br />an approved testin, laboratory of each si.ze of bar to,be applied by the; manufac-
<br />turer on the contract frorn each ten (10) ton lot or less aahenever the Inspecter
<br />of Buildings ma.y demand sixch •test.s; . and: certifiesi copies of al1 test reeords are
<br />tn be submitted to him- for exainination ulnon iiis requesta
<br />Hot twisted bars of hioh carbon,..steel shall be turisted ,with ors complete
<br />twist in a length equal to not more than twelve (12,) times thd:thiclzness of the
<br />bar, , . . .
<br />- The Inspector of Buildings may demand the owners, Uuilcler, .coztraetor,
<br />sub-contractor, or foreman to make, or cause, to _be ,made, ben.ding. te:st.s in the
<br />field, on all grades of rein£orcirxg steel, then tntheir opinion there is any
<br />doubt-as`to ,?hdther tlze reinforcing steel is-up to the standard of -Ghese regula-
<br />tions. - . . ;. .
<br />`hese bending-tests shall be thase specified,in the above mentioned t'stan-
<br />-dard Specifications."
<br />Sec.145. PLACING CONCRETE AND STEEL. In filling in coilcrete around re-
<br />inforaing steel, the concrete must be worked continuousl.y with suitable tools as
<br />it isput in place. Filling the columns comple,tely and puddling afternvards will
<br />--not be pernit-ted. -In placing'-the concrete the.w,orl.•_shall, be so laid out that par-
<br />t;i`ally set' concrete will not=be subjected ta;:shocks -fro.n the wheelin.g or handling
<br />? „_
<br />`?laterial over it.'- Concr'ete placed in ?rarm .v?eather shall be drenched withvuater
<br />twice ciaily, Sun.day includec7_, during, the. first we.ek after being put in place.
<br />iidhen it is not possible- to cast an entire structure in one operatio4 the
<br />" work should be stonped; ^for ' colurnns at..the: underside _..of girders for girdere at a
<br />point mi.dway,between supports, unless'a beam sllould occur at this point;.in a?liich
<br />case the joint should be offset a distance eaual to,ttvice the width of the beam;
<br />forslabs at the center of the span.., . , . ,
<br />When work is resumed the eoncrete previously placed shall be cleared of
<br />'all foreign material, dxenched .and slushed with mortar composed; of one l l) part
<br />cement and one (1) part sand. . ,
<br />Beams and girders sha11 not be constructed over freshl:y placed columns
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