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Title: Effect OF Weight Of Tampers And Number Of Tamps On The Flexural Strength Of Concrete Silo Staves

Author(s): C. A. Hughes, Dalton G. Miller, and Philip W. Manson

Publication: Journal Proceedings

Volume: 36

Issue: 9

Appears on pages(s): 37-48

Keywords: none

Date: 9/1/1939

Abstract:
Reports tests of 502 concrete silo staves made at commercial plants. The transverse strengths were de- termined for 324. The chief variables were the weight of tampers and the number of tamps per stave. The number of staves per sack, the aggregate grading, and the consistency were also varied. For the materials and methods of manufacture used - (a) Increasing the weiaht of the tampers from 50 to 75 lb. increased the transverse strength’, the increase varying’ both with the number of tamps and the mix. (b) The transverse strength increased ‘with increase in ‘number of tamps from 2 to 6 tamps. Beyond 6 tamps the effect on the transverse strength was influenced also by the mix and by the weight of the tampers. (c) In nearly all cases staves made with 2 tamps of the heavy tamper were stronger than staves made with 6 tamps of the normal one. (d) The thickness of tamped staves varies considerably. Hence if the load per inch of width is to be used as a measure of quality, it should be cor- rected to correspond to a specified thickness.considerably. Hence if the load per inch of width is to be used as a measure of quality, it should be cor- rected to correspond to a specified thickness.