. Engineering research series . made on the speci-mens of Series II. In Series III, two of the compression specimens of each kindwere tested at the age of three months. In those cases whereresults of the two tests did not agree closely, a third specimenwas tested. Testing. A wire wound dial compressometer was used tomeasure the deformation taking place in the test of these speci-mens. This apparatus is shown in the sketch, Fig. 13. It con-sists of two yokes attached to the specimen by four pointedthumb screws, two in each yoke, and placed ten inches apart bytwo removable spacing bars. On one s
. Engineering research series . made on the speci-mens of Series II. In Series III, two of the compression specimens of each kindwere tested at the age of three months. In those cases whereresults of the two tests did not agree closely, a third specimenwas tested. Testing. A wire wound dial compressometer was used tomeasure the deformation taking place in the test of these speci-mens. This apparatus is shown in the sketch, Fig. 13. It con-sists of two yokes attached to the specimen by four pointedthumb screws, two in each yoke, and placed ten inches apart bytwo removable spacing bars. On one side the yokes are main-tained a constant distance apart by a bar connected at the topand bottom by ball and socket joints closely held by smallsprings, while on the other side the movement is measured bymeans of a pointer moving over a dial fastened to the upper yokeand graduated to read to two ten thousandths of an inch. Thispointer is connected to a small cylinder, free to turn, around Physical Properties of Dens( ConcreU 35. Fig Compressometer. which passes a fine wire, one end of which is attached to thelower yoke, a small weight being connected to the other the two yokes are in effect pivoted on the side where theconstant distance bar is, the other side, to which is alt ached thedial, moves twice the distance that the two screw points move,provided these have been correctly placed half way between thebar and dial. This movement is transmitted by the wire to thecylinder which is made to turn and the amount of shortt ning isthus determined, readings of actual deformation as close as oneten thousandth of an inch being- obtained. The apparatus was carefully attached to the specimen to betested about midway between the top and bottom, the screwpoints being- centered as near as could be done by eye. Thespecimen was then placed on the machine, the spacing- bars re-moved, and the pointer set to read zero. The load was appliedby increments of from 5000 to 20,000 pounds, depe
Size: 1504px × 1661px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectenginee, bookyear1915
