Determination of shear modulus of wood joists from torsion tests and relationship with modulus of elasticity

Khokhar, Aamir; Zhang, Johnson

Abstract

This paper presents the work that was undertaken to use torsion tests to evaluate the shear modulus of wood joists. The relationship of the shear modulus with modulus of elasticity, obtained from bending tests, was examined. Testing standard EN408 have recommended torsion test to determine the shear modulus of structural-size timber. However, shear modulus values in EN338 are determined from modulus of elasticity using the modulus of elasticity to shear modulus ratio of 16 to 1(16:1). This work has found no evidence of correlation between these two mechanical properties. It was found that modulus of elasticity to shear modulus ratio depends on wood species and the strength grade of timber. A substantial variation in shear modulus (10 to 30%) was noticed along the length of test joists. However, in this study, it was seen that the variation was not influenced by knot or other wood defects.

Citation

Khokhar, A., & Zhang, J. (2018, August). Determination of shear modulus of wood joists from torsion tests and relationship with modulus of elasticity. Presented at World Conference on Timber Engineering, Seoul, Republic of Korea

• Presentation Conference Type: Conference Paper (published)
• Conference Name: World Conference on Timber Engineering
• Start Date: Aug 20, 2018
• End Date: Aug 23, 2018
• Acceptance Date: Jan 18, 2018
• Publication Date: Aug 20, 2018
• Deposit Date: Jul 22, 2019
• Chapter Number: In CD-ROM Proceedings of the World Conference on Timber Engineering (WCTE 2018)
• Keywords: torsion tests; wood joists; elasticity; wood species; timber
• Public URL: http://researchrepository.napier.ac.uk/Output/1671125