1927 086 Ordinance - Laserfiche WebLink

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Sec.150. T'EST OF CONC=HmE BLOCKS. All concrete materials made of Portland cement, sand and crushed roci or gravel, _or cement and_sand, ivhich are larger than the standard brick size and which are molded and then set in place in the stru.c- ture shall come under the provisions as follows: (a) Applications for Tests.. Before any concrete block is used in a building an application for its use and for a test of the same shall be filed with the De- .. partment.of Buildings, A.description of the materials and the manufacture of satne shall be filed with the application., • . (b) Tests to be Made. The concrete blocks shall be subject to the follow- ing tests: Con7pression9 transverse and absorption, . ' All such tests shall.be made in so.me laboratory of recognized standing under the supervision of the Buildinb Inspector or his authorized ager_t. The tests shall be,made at the expense of the owmer. , (e) For the purpose of these tests at least ten (10) samples of test pisces - , shall be provided. S-a.ch samples shall be selected from stock by the Building In- spector, or his autlzorized agent, or may be macle in the presence of such represen- tative. i'he sasnples shall be of the regular size as used in colzstruction, except that evhen the samples are too.large to use in the ordinary testing machines, in which case sma.ller sized blocks shall be ma.de for testiiig under the directioiz of the. Building Inspector or his aiithorized agent. , (d) Tests shall be made in a series of at least tnree (3) composed of four (a).sanples each. The transverse test shall bo made on fu11 size samples. Half size samples may be used.for the.crushirg, test, and the remaining samples are to be Irept in reserve in case-exceptioiiallyhigh values are shoevn by these tests which may maYe it necessa.ry to disca.rd certain of theme All saniples mu.st be marked for identification and comparison. The weight of the material in the block per cubic foot ahall be determined. (2) Transverse Testa The transverse test shall be made as follavls. The samples 'shall be placed flatwise on two (2) rounded kniie-edge bearings set para- lel and seven (7) inches a.parte; g load is then applied on top of the test piece midway between the suprorts and transmitted through a similar round lnife-edge un- til the rupture of the sampleo The modulus of rupture shall tie determined by m#l- -tiplying the toi;al breaking load in pounds by twenty-one (21) ninus three (3) times the dista.nce between. the supports in inches and. then dividing the results thus ob- tained by tw3ce the product of the width in in.ches by the square of the. depth in inches. Allovrance shall be made in.figuring the modulvs of rupture for the hollowr spaces in the test piece. , 3Wy Modizlus of rupture R equals 2B2 Af) The.Compression Test. The compression tests shall be mde as folJ.ows:' ,. Samples shall be cut i.n blocks. in such a, nianner as to contain the flzll web aection. The samples must be carefully.measured, then bedded fls.twise in plaster of Parie to secure uniform bearing in the testing ma.chine, and then cn-ished. The t otal ..-.breaking load is,.then divided by the ar,e& of_ square inches in compression. De- duction to be made for hollow spaces. . . (g) Absorption Test. '1'he absorption ihest must be rnade as follovrs: The . b1oGk is first to-be thoroughly dried and weightd. It is t hen to be.placed in