R F S Hearmon 1943 Proc. Phys. Soc. 55 67 doi:10.1088/0959-5309/55/1/309
R F S Hearmon
Show affiliationsThe effect on the elastic behaviour of wood and plywood of coefficients such as s'16 (coupling coefficients) in the generalized Hooke's Law is considered. It is shown that for specimens cut at angles to the principal directions, these coefficients may differ from zero. This implies a difference between "pure" and "free" elastic constants for such specimens, a difference which is verified experimentally. The existence of coupling coefficients introduces uncertainties into the calculation of the free Young's and rigidity moduli from the frequencies of flexural and torsional vibrations, but it is shown that the free constants can be measured to sufficient accuracy by working on specimens of suitable length. Finally, it is shown that the elastic behaviour of plywood cut at an angle to the grain may be determined as much by the pure elastic constants of the individual plies as by the free constants.
81.40.Jj Elasticity and anelasticity, stress-strain relations
Issue 1 (1 January 1943)
R F S Hearmon 1943 Proc. Phys. Soc. 55 67
Hui Li et al 2006 Smart Mater. Struct. 15 1039
Robert Bartnik 2004 Class. Quantum Grav. 21 S59
S Mukherjee (for the LIGO Science collaboration) 2006 J. Phys.: Conf. Ser. 32 44
Pierre Otal et al 2008 Metrologia 45 07004
Peter T Beyersdorf et al 2002 Class. Quantum Grav. 19 1585
V Yazdanpanah et al 2006 New J. Phys. 8 233
L G Moretto and R P Schmitt 1981 Rep. Prog. Phys. 44 533
C H Sim 2007 Metrologia 44 29
T A Kaplan and S D Mahanti 1979 J. Phys. C: Solid State Phys. 12 L23