Question $3(9$ points$)$

Consider the anchored sheet pile problem shown in Figure $1,$ which supports an excavation site for an underground

metro tunnel in Melbourne, and answer following questions using Optum G$2($Lower Bound and Upper Bound

analyses$).$

I.

Assuming an anchor of infinite strength, determine the smallest possible wall yield moment $(2$ points$).$

II$.$

Assuming a wall of infinite strength, determine the smallest possible anchor force $(2$ points$).$

III.

Determine a sufficient number of solutions in between those found in Parts I and II to determine the range

of allowable combinations of wall yield moment and anchor strength $(5$ points$).$ You need to generate a

plot for yield moment versus anchor strength.

Mohr$-$Coulombc$=8$ kPao$=22$Y$=19$ kN$/$m$^32$ m T$12$ m$4$ mFigure $1.$ Problem definition and material properties in Question $3.$