Question three: sheet pile, $7\mathrm{.}5m$ high, retains a cohesionless backfill. The top $5m$ of the fill has a unit weight of $18k\frac{N}{m^3}$ and $=30$ and the rest has a unit weight of $30k\frac{N}{m^3}$ and $={30}^{**}.$ Determine the do$,d,R$ and the maximum bending moment $Ka=0\mathrm{.}28,K{p}_p=4\mathrm{.}6,FS=2$

Use NPPM method

$20$ mark

$H=5m$

${}_{\text{a}\text{a}\text{t}}=k\frac{N}{m^3}$

$=30$

$d=m$