Experimental approach about fracture process in timber elements under mechano-sorptive effects

This paper deals with the fracture problem in timber structures subject to mechanical and climatic loadings. Mechanical tests illustrate local and global fracture properties at different moisture content levels on DCB specimens of douglas fire. It is shown the dependence of moisture content in terms of compliance and energy release rate. To highlight the hygro-mechanical coupling, tests employ an electromechanical press associated with an environmental chamber in which humidity and air temperature are regulated. Two families of tests are performed, the first in dry state conditions and the second in a wet state conditions. The main objective of this paper is to fix first experimental results in order to integrate, in future works, mechano-sorptive effects on the crack growth process by taking into account moisture content variations in the crack tip vicinity associated with sorption kinetics