Mode I fracture of wood: a systematic review of experimental and numerical advances

Purpose. This paper presents a systematic literature review on Mode I fracture of wood in order to identify the research trends, highlight existing gaps and guide future studies. Design/methodology/approach. The research methodology is designed in two steps: (1) bibliometric analysis and (2) publication overview. In the first step, two main databases were used to identify relevant publications and analyze research trends, historical chronology, citations and geographical distribution. While in the second step, selected studies were overviewed across different topics to determine advancements and gaps in the field.FindingsThe field is dominated by experimental research, with a growing use of mixed and numerical methods. The topics were categorized as follows: (1) established topics (wood species, test type, size effect, cracking system, growth ring effect, density and wood structure effect); (2) ongoing topics which need further investigation (heat treatment effect, moisture content effect, numerical modelling, advanced measurement methods such as digital image correlations (DIC) and acoustic emissions (AE) and (3) unestablished topics (loading rate). After identifying the gaps, it is suggested further simulations on heat treatment, the impacts of moisture, improving the application of DIC, AE and their combination, considering the fiber bridging phenomena in the simulations, developing more 3D models, performing experimental campaign for better understanding the loading rate effect and finally more experimental and/or numerical studies on cyclic loading under different testing conditions. Originality/value. The report provides previous findings on mode I fracture of wood and can be regarded as a comprehensive reference for guiding further experimentations and/or simulations to fill in the gaps.