Mode-II progressive fracture of sawn timber and timber-adhesive bond: experimental evaluation of end notched flexure (ENF) testing using DIC

Abstract The end-notched flexure (ENF) testing technique has been used in this paper to investigate the Mode II fracture behaviour of sawn timber and timber-adhesive bonds. Mode-II strain energy release rates were obtained by using classical data reduction schemes based on actual crack lengths captured digital image correlation (DIC) technique. compliance-based beam method (CBBM), which does not require length measurements, was also evaluated for its suitability timber. Utilizing forward shear slip measurement from DIC at every millimetre length, a simple yet effective innovative identify tip opening monitor proposed herein. Three different initial notch widths current study examine their producing reliable initiation consistent bond delamination solid glued calculated equivalent values showed similar trends resistance curves, are commonly known as R but rate ( G II0 ) critical IIC two methods some discrepancies. Equivalent CBBM found be inadequate determining despite stable steady after initiation. Experimental results that line is relatively more brittle than fracture, average IIc 14% greater Based experimental observations, specific test criteria ENF structures paper.