Thermal Degradation of Bending Properties of Structural Larch Wood

Abstract

Wood is being used extensively in timber construction in China. It is important to understand its response when exposed to elevated temperatures. In fire-resistant design for timber construction, the main goal is to ensure that enough structural integrity is maintained during a fire to prevent structure collapse. To study the effect of temperature on bending strength (MOR) and stiffness (MOE) of solid clear wood from Chinese larch, a total of 108 samples with various target temperatures were tested in static bending under same temperatures to ensure the wood temperature to be sustained. The results indicated that exposure to sustained temperatures caused significant degradation of bending strength and stiffness. The degradation of chemical composition of larch wood happened after 170 °C and caused a serious drop in mechanical properties of larch wood after 225 °C. The bending strength and MOE of larch wood behaved negative linear relationship with temperatures before 100 °C.