Chapter 16.2, Problem 40P

A glue-laminated column of 3-m effective length is to be made from boards of $\text{24 × 100-mm}$ cross section. Knowing that for the grade of wood used, $E=\text{11 GPa}$ and the adjusted allowable stress for compression parallel to the grain is ${\sigma }_C=\text{9 MPa,}$ determine the number of boards that must be used to support the centric load when $\left(a\right)P=\text{34 kN, }\left(b\right)P=\text{17 kN}\text{.}$