The elastic properties of concrete under bi-axial loading . e vertical direction malcing theloads equal. The arraiigement of the loadinr^ apparatus for the crossedbeans is taken up in 8. Description of Apparatus, The loadwas very slowly applied in increments of 15000-lb. betweenseries of observations. The pointer on the dynamometer couldbe quite accurately read and it was found easy to stop at anydesired load. Failure could be predicted by a baclcward motionof the dynamometer needle between strol^es of the pmp and arapid falling off of ihe load when the pump was stopped. Thesame indications of
The elastic properties of concrete under bi-axial loading . e vertical direction malcing theloads equal. The arraiigement of the loadinr^ apparatus for the crossedbeans is taken up in 8. Description of Apparatus, The loadwas very slowly applied in increments of 15000-lb. betweenseries of observations. The pointer on the dynamometer couldbe quite accurately read and it was found easy to stop at anydesired load. Failure could be predicted by a baclcward motionof the dynamometer needle between strol^es of the pmp and arapid falling off of ihe load when the pump was stopped. Thesame indications of failure were present in the 8-in. cube testsin v/hich a dynamometer was used to indicate the load. 10. Time STfect of in the first stages of atest, the load fell off while a series of readings was beir^^tax en, both in the compression tests and in the beam tests. Aseries of readings required from fifteen to thirty minutes,depending on the number of observations made, time taken toobserve phenomena of the tests and the personnel of the party,. 59 and during this time :iie change of load was often is probable that concrete does not adjust itself to a nev:condition of stress speedily, and that during the time consumedin talcing; the whole number of readin£;s, the specimen \7asundergoins internal changes. In a test, the readings v;ere taken in the order of thenumber of the gauge-line, but a study of these readings andof the plotted curves does not sho7, a relation betrzeen thedeformation and the number of the point, uhich is to say thatthe nevr condition of stress in the specimen at the time of thelast observations of the series \7as not enough different fromthe condition at the time of the first observations to benoticed by instruments as delicate as those used in these tests. In the test of 2071 the pov;er on the testing machine failedafter the first increment of load had been applied and it rrasnecessary to leave the specimen in this condition over
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttheses, bookyear1912
