Determining the Shear Modulus of Sitka Spruce from Torsion Tests

Khokhar, Aamir; Zhang, Hexin; Ridley-Ellis, Daniel; Moore, John

Abstract

This paper presents details of the experimental method, and preliminary results from, a series of torsion tests undertaken to evaluate the shear modulus of Sitka spruce (Picea sitchensis) timber. Direct torsion tests were used to determine the variation of shear modulus within and between pieces of timber with rectangular cross-sections and with lengths ranging from 1 m up to 3.6 m. Preliminary results obtained indicate that there was considerable variation in shear modulus between pieces of timber tested, but that there was no relationship with the modulus of elasticity in bending, or knot area. Approximately 33 percent of the variation in shear modulus was due to variation along the length of a piece of timber sample. More detailed investigation of the shear transfer mechanism within a timber beam is required, particularly to identify those physical and anatomical characteristics which influence the shear properties.

• Conference Name: WCTE2008:10th World Conference on Timber Engineering
• Start Date: Jun 2, 2008
• End Date: Jun 5, 2008
• Acceptance Date: Feb 4, 2008
• Online Publication Date: Jun 2, 2008
• Publication Date: Jun 2, 2008
• Deposit Date: Apr 25, 2017
• Publicly Available Date: Apr 26, 2017
• Publisher: Engineered Wood Products Association
• Pages: 2137-2144
• Book Title: 10th World Conference on Timber Engineering 2008
• Chapter Number: 3
• ISBN: 9781615670888
• Keywords: Torsion, timber, Sitka spruce,
• Public URL: http://researchrepository.napier.ac.uk/Output/833209
• Contract Date: Apr 25, 2017