Thermo-hygro-mechanical behaviour of notched beams of European species under creep loadings in outdoor conditions

摘要

The main objective of this study is to know, the coupled impact of climatic variations (relative humidity, moisture content and temperature), wood defects (crack initiations and crack propagations) and the creep loading on the behavior of the notched beams of European species: white fir (Abies Alba Mil, WF) and Douglas fir (Pseudotsuga Menziesii, DF). After machining, the beams were stored at room temperature (Relative humidity 22% and Temperature of 12℃). The beams have been notched at the ends and loaded in 4-point bending test. The crack propagation and the climatic parameters, were monitored manually every hour from 8 am to 9 pm, during 10 days. The results show that, the climatic variations have a significant impact on the rise of the beam deflection and on the crack opening.