Effect of the Strain Rate and Fiber Direction on the Dynamic Mechanical Properties of Beech Wood

Abstract

As a macroscopically orthotropic material, beech wood has different mechanical properties along the fiber direction and the direction perpendicular to the fiber direction, presenting a complicated strain rate sensitivity under impact or blast loadings. To understand the effect of the strain rate on the mechanical properties of beech wood, dynamic compression tests were conducted for the strain rate range of 800 s−1–2000 s−1, and quasi-static compression tests for obtaining the static mechanical properties of beech wood were also performed for comparison. The fiber direction effect on the mechanical properties was also analyzed, considering two loading directions: one perpendicular to the beech fiber direction and the other parallel to the beech fiber direction. The results show that beech wood for both loading directions has a significant strain rate sensitivity, and the mechanical properties of beech wood along the fiber direction are superior to those along the direction perpendicular to the fiber direction. An analysis of the macrostructures and microstructures of beech specimens is also presented to illustrate the failure mechanisms. The beech wood, as a natural protective material, has special dynamic mechanical properties in the aspect of transverse isotropy. This research provides a theoretical basis for application in protective structures.

Determination of Elastic Properties of Beech Plywood by Analytical, Experimental and Numerical Methods

“…In most of the tests performed, the mechanical properties of the dynamic tests were higher than those of the static tests [32][33][34]. However, even more obvious were the differences between the mechanical properties obtained at very high strain rates and those obtained in the quasi-static tests; the former differences are much higher [35].…”

Crashworthiness of poplar wood veneer tubes

“…During Hopkinson or weight-down crushing to assess the effect of the speed of the stress on the behaviour of the wood material [9][10][11][12][13], it was found that the average stress increased with the dynamic effect, causing an increase of the energy absorbed and therefore of the SEA.…”

“…Johnson analysed the problem in 1986, mainly from a historical point of view in the naval field [8]. Some studies have been carried out to study the dynamic behaviour of wood via tests on Hopkinson bars [9][10][11][12] but few dynamic studies have been carried out on drop weight apparatus. Adalian and Morlier [13], however, studied the behaviour, in the longitudinal and tangential directions, of poplar in the form of massive rectangular specimens with this kind of tests.…”

The viscoelasticity and deformation mechanism of Taxodium hybrid ‘Zhongshanshan’ wood by dynamic mechanical analysis

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