Problem $2-$ Fire analysis of a timber column

A column $($glue$-$lam$)$ is exposed to a standard ASTM$-$E$119$ fire. The column is $250250mm$

in cross section $(\frac{C}{S})$ and is of $3000mm$ length. The column is subjected to dead and live

loads of $50kN$ and $60kN$ respectively and exposed to fire on all four sides. The charring rate

of wood is $0\mathrm{.}65m\frac{m}{m}in$ and the buckling factor for this short column is $0\mathrm{.}95.$ Assuming that

the compressive strength and stiffness to be $13\mathrm{.}1$MPa and $11,721$MPa respectively, and the

effective length factor $(K)$ to be equal to $1$ :

$($a$)$ Calculate the strength of the column at $60$ minutes using effective $\frac{C}{S}$ method

$($b$)$ Calculate the strength of the column at $60$ minutes using reduced properties$($crushing of

materials$)$ method

$($c$)$ Calculate the strength of the column at $60$ minutes using reduced properties, with corner

rounding, method

$($d$)$ Determine fire resistance of the column using "correlation method".