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Access Type
Open Access
Document Type
thesis
Degree Program
Environmental Conservation
Degree Type
Master of Science (M.S.)
Year Degree Awarded
2012
Month Degree Awarded
September
Keywords
Torsion; Shear; Size Effect; Structural Composite Lumber; Experiment; Universal-type Test Machine; Finite Element Analysis
Abstract
The natural variation of strength properties within brittle materials leads to size effect, a well-known phenomenon whereby the mean strength of a material is observed to decrease as the stressed volume increases. An important implication of size effect is that size adjustment parameters must be incorporated into multi-axial constitutive and failure models used in numerical simulations to predict material response to loading. This experimental study seeks to verify and quantify the presence of depth effect under shear failure in the orthotropic principal material directions of parallel strand lumber (PSL) and laminated veneer lumber (LVL). Torsion tests have been performed on specimens of fixed length and differing cross section to get a pure shear failure, by using a Universal Test Machine. The experimental results indicate that there is no depth effect for LVL from torsional shear stresses. PSL testing was limited to one size, and depth effect was not evaluated. A finite element model was built to simulate the torsional test for the 44x140mm LVL specimen. Comparing the experimental test results and the simulation results, the model provided an accurate prediction of the torsional test for Structural Composite Lumber.
DOI
https://doi.org/10.7275/2878593
First Advisor
Peggi L. Clouston
Second Advisor
Sanjay R. Arwade