Summary
Deflections of wooden beams loaded repeatedly for seven or two days in every 14 were compared with those of beams under constant load over a period of six months in a constant environment. Four load levels were applied to beams of three species. Loads ranged from 17 to 67 per cent of short-time failing load estimated from matched specimens. The deflections under intermittent loads were lower than the creep deflections under constant load and, with the exception of material under high stress, applicability of Boltzmann's principle of superposition of deformations was confirmed. Non-linearity at high stresses is linked with other signs of weakening after application of loads in excess of about 50 per cent of short-time ultimate.
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At the time of the study this author was working with the CSIRO Division of Building Research, Australia, under a fellowship provided by the Japanese Government
The authors express their appreciation of the advice and help received from Miss N. Ditchburne of the CSIRO Division of Mathematics and Statistics
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Nakai, T., Grossman, P.U.A. Deflection of wood under intermittent loading. Wood Sci. Technol. 17, 55–67 (1983). https://doi.org/10.1007/BF00351832
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DOI: https://doi.org/10.1007/BF00351832