Relation Between Static and Dynamic Modulus of Elasticity of Wood
نویسندگان
چکیده
Static and dynamic modulus of elasticity (MOE) of spruce lumber were determined under different conditions like cross head speed, bending and longitudinal vibration, and mode numbers. The characteristic time of MOE determination is introduced. Characteristic time is defined as the typical MOE determination time. Shorter characteristic times are shown to result in higher MOE values. An order of magnitude change in characteristic time resulted in a 1.7% change in MOE. We found clear evidence that creep exists on a short time scale. modulus of elasticity / static and dynamic determination / creep wood Kivonat – Kapcsolat a faanyag statikus és dinamikus rugalmassági modulusza között. Lucfenyő fűrészárú rugalmassági moduluszának meghatározását a mérési körülmények befolyásolják, úgy mint a az anyagvizsgáló gép sebessége, dinamikus mérés esetén a hajlító és longitudinális rezgések, illetve az alkalmazott módusok száma. A rugalmassági modulusz meghatározásának jellemzésére a karakterisztikus időt vezettük be, mely a mérésre fordított időt jelenti. A rövidebb karakterisztikus idő magasabb rugalmassági moduluszt eredményez. Egy nagyságrend változás a karakterisztikus időben, 1,7% változást jelent a rugalmassági modulusz meghatározásában. Ez egyértelmű bizonyítéka a kúszás jelenségének rövid időtartományokon. rugalmassági modulusz / statikus és dinamikus meghatározás / kúszás / faanyag
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