Machine Stress Rated (MSR) and Machine Evaluated (MEL) Lumber
Grading of lumber in North America
MSR - Machine Stress Rated Lumber
MSR is lumber that has modulus of elasticity E evaluated by mechanical stress equipment, with each piece being marked to indicate the modulus of elasticity E.
- Fb - allowable 10-year load duration bending stress parallel to grain
- E - modulus of elasticity
- Ft - allowable 10-year load duration tensile stress parallel to grain
- Fc - allowable 10-year load duration compressive stress parallel to grain
MEL - Machine Evaluated Lumber
MEL is lumber where a parameter like density is evaluated nondestructively by mechanical grading equipment to predict certain mechanical properties. A MEL machine evaluates each piece and sorts each piece into various strength classification grade categories.
• Beams and Columns
Deflection and stress, moment of inertia, section modulus and technical information of beams and columns.
Wood - Densities of Various Species
Densities of various wood species - apple, ash, cedar, elm and more.