The length effect on Norway spruce boards: An investigation on indicating properties based on axial dynamic and edgewise bending MOEs
Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
When using timber for construction purposes it is important to know its strength. One way to do this is by sorting the boards into strength classes that are defined by European standards. A commonly used method for strength grading is based on dynamic excitation in the longitudinal direction of the board to obtain an average dynamic longitudinal modulus of elasticity (MOE). This in turn correlates with the bending strength of the board in such a way that it can be used as an indicating property (IP) to bending strength. The use of MOE as an IP has proven to give the highest coefficient of determination (R2) to both bending and tensile strength in boards. Through the research described in this thesis, one might find that both reducing the length of a board to half its initial length and by removing the part containing the lowest local MOE in edgewise bending provided similar results, the axial dynamic MOE remaining within a 1% tolerance whereas the lowest IP based on local MOE in edgewise bending increased by 6–7%.
Place, publisher, year, edition, pages
2015. , 50 p.
length effect, dynamic modulus of elasticity, edgewise bending, indicating property, Norway spruce
Engineering and Technology
IdentifiersURN: urn:nbn:se:lnu:diva-49099OAI: oai:DiVA.org:lnu-49099DiVA: diva2:896152
Subject / course
Structural Engineering, Master Programme, 60 credits
Oscarsson, Jan, Universitets lectorOlsson, Anders, Proffesor
Dorn, Michael, Doctor