\r\nusing torsion test or shear field test method. The shear field test

\r\nmethod is based on shear distortion measurement of the beam at the

\r\nzone with the constant transverse load in the standardized four-point

\r\nbending test. The current code of practice advises using two metallic

\r\narms act as an instrument to measure the diagonal displacement of

\r\nthe constructing square. The size and the position of the constructing

\r\nsquare might influence the shear modulus determination. This study

\r\naimed to investigate the size and the position effect of the square

\r\nin the shear field test method. A binocular stereo vision system has

\r\nbeen employed to determine the 3D displacement of a grid of target

\r\npoints. Six glue laminated beams were produced and tested. Analysis

\r\nof Variance (ANOVA) was performed on the acquired data to evaluate

\r\nthe significance of the size effect and the position effect of the square.

\r\nThe results have shown that the size of the square has a noticeable

\r\ninfluence on the value of shear modulus, while, the position of the

\r\nsquare within the area with the constant shear force does not affect

\r\nthe measured mean shear modulus.","references":"[1] BSI, BS EN 408:2010+A1:2012: Timber structures - Structural Timber\r\nand Glued Laminated Timber - Determination of Some Physical and\r\nMechanical Properties. London, UK: The British Standards Institution,\r\n2010.\r\n[2] D. S. Riyanto and R. Gupta, \u201cA Comparison of Test Methods for\r\nEvaluating Shear Strength of Structural Lumber,\u201d Forest Products\r\nJournal, vol. 48, no. 2, pp. 83\u201390, 1998.\r\n[3] R. Brandner, B. Freytag, and G. Schickhofer, \u201cDetermination of shear\r\nmodulus by means of standardized four-point bending tests,\u201d in CIB W18,\r\nno. August, St. Andrews, Canada, 2008, pp. 41\u201321\u20131.\r\n[4] R. Brandner, E. Gehri, T. Bogensperger, and G. Schickhofer,\r\n\u201cDetermination of modulus of shear and elasticity of glued laminated\r\ntimber and related examinations,\u201d in CIB-W18, Bled, Slovenia, 2007, pp.\r\n40\u201312\u20132.\r\n[5] BSI, BS EN 338:2016: BSI, Structural Timber Strength Classes. London,\r\nUK: The British Standards Institution, 2016.\r\n[6] C. Wohler, 3D computer vision: efficient methods and applications,\r\n2nd ed. London, UK: Springer, 2013.\r\n[7] A. Valsaraj, A. Barik, P. Vishak, and K. Midhun, \u201cStereo Vision System\r\nImplemented on FPGA,\u201d Procedia Technology, vol. 24, pp. 1105\u20131112,\r\n2016.\r\n[8] N. Gharavi, H. Zhang, Y. Xie, and T. He, \u201cEnd effect on determining shear\r\nmodulus of timber beams in torsion tests,\u201d Construction and Building\r\nMaterials, vol. 164, pp. 442\u2013450, 2018.","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 135, 2018"}