CIVL439/WOOD476 ShearFull ize Shear Full e Difficult to induce shear failures in bending members yet shear strength sometimes governs with a Bending Strengths Properties Small Clear Bending Tests MOE and MOR In-Grade Testing In-Grade Testing ■■ (nd grade) esign properties seem ove fmprcnewvsualgradingnules 13CIVL439/WOOD476 13 Shear Strength of Full Size Members • Difficult to induce shear failures in bending members yet shear strength sometimes governs design of timber beams • Based on ASTM shear block tests with a conversion factor for full size (3.15 to 4.1) Shear Strength of Full Size Members Douglas fir PSL 0 60 0.70 0.80 0.90 1.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 2.00 4.00 6.00 8.00 10.00 12.00 14.00 Apparent Shear Strength (MPa) CDF Center pt - 44x184 Joist Center pt - 44x305 Joist 5 pt - 44x184 Joist 5 pt - 44x305 Joist Center pt - 44x184 Plank Center pt - 44x280 Plank Bending Strengths Properties MOE and MOR Small Clear Bending Tests In-Grade Testing Grade Testing • Mechanical properties of Canadian dimension lumber (PI: JDB and FL) ¾ Harmonization of results from different test standards (e.g. AS/NZ, CEN) ¾ Coastal species • Japanese market (sizes and grades) (N≅10000) ¾ Current design properties seem over conservative ¾ Impact of new visual grading rules h/2 h 153 mm 6h 6h h 18h 10h p p h Random Position of MSRD Mid-span deflection measurement device In-Grade Testing Grade Testing