Question $3$a

The cross section of a column built up of a timber section $(E=13$GPa $)$ is shown in Figure $5.$

Figure $5.$

The cross$-$section of the column is a rectangle with dimensions $120mm200mm.$

The column built into the ground has length, $L=2\mathrm{.}8m,$ and is under axial compressive load $P.$

Use $K_e=2\mathrm{.}0.$

Calculate:

i$.$ The critical $($Euler$)$ load to buckle the column.

$(5$ marks$)$

ii$.$ If the factor of safety is F$.$S$.=2\mathrm{.}0,$ what is the allowable buckling load?

$(2$ marks$)$

Question $3$b

The Universal Column $310$UC$118\mathrm{.}0$ is used to construct a column with height of $10m$ and fixed at base and pinned at top.

Determine the total critical $($Euler$)$ load. $Es=200$GPa