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steel may not be displaced. Note that all steel has its 

 proper position before concreting. 



When filling columns fill same to bottom of beams or 

 girders. Churn same thoroughly with a long pole so 

 as to work the concrete into close contact with the re- 

 inforcement. After being allowed to set for several hours 

 the beams and slabs may be placed. Column forms are to 

 be filled before the reinforcement for beams and slabs is in 

 place. 



Reinforcement: All steel should be medium steel, hav- 

 ing an ultimate tensile strength of from 60,000 to 68,000 

 Ib. per sq. in. and an elastic limit of not less than % the 

 ultimate strength and should elongate not less than 22% 

 in 8 in. and bend cold 180 around a diameter equal to 

 the thickness of the piece tested without fracture on out- 

 side of bend. If high carbon steel is used it should con- 

 tain not more than 0.06% of phosphorus; not more than 

 0.8% of sulphur; not less than 0.4% or more tuan 0.8% of 

 manganese and should contain from 0.5 to 0.6% of carbon. 

 Its ultimate tensile strength should be at least 100,000 Ib. 

 per sq. In. ; elastic limit of half the ultimate strength, 

 elongation of 10% in 8 in. for a test piece of % in. to % in. 

 in dlameted. A % in. test piece should bend 110 without 

 fracture around a piece of equal diameter. 



Steel in compression should have a working value of 

 10,000 Ib. per sq. in. 



In shear 10 to 12,000 Ib. per sq. in. Is allowable. 



All bars for column reinforcement should be cut with 

 square or milled ends, especially if they are over 1% in. 

 diameter. 



All steel should be bent as per details furnished. Most 

 companies have a standard system of bending. 



All stirrups .should be placed in the position shown on 

 drawings and never placed a greater distance than the 

 effective depth of the beam. 



The column hoops or spirals should be properly spaced 

 and wired to the vertical steel, depending on the size of 

 the column and never exceeding the diameter of the 

 column less 4 in. Before putting column steel on footings, 

 the bearing plates should be properly grouted in place and 

 all sawdust or rubbish removed. No more steel should be 

 placed until the columns have been concreted. Beam, 

 girder and slab steel is next placed and should be properly 

 wired to secure it in its desired position. Before con- 

 creting examine all steel to make certain none of its has 

 been pushed out of position or omitted. 



