You will be supporting a building with a structural columns and a reinforced concrete mat

foundation in Norfolk, Virginia. Properties of the soil column are:

$$ the clay is normally consolidated;

$$ the clay layer is VERY thick;

$$ the initial void ratio e o $=1\mathrm{.}25$;

$$ the compression index Cc $=0\mathrm{.}30$;

$$ the total unit weight

$\backslash$gamma $=110$ pcf; and

$$ the water table is at the ground surface.

Properties of the mat and structural columns are:

$$ the mat is rectangular with dimensions of $50$ ft x $60$ ft x $2\mathrm{.}0$ ft $($B x L x thickness$)$;

$$ the mat is reinforced concrete with a unit weight of $145$ pcf;

$$ there are $42$ concrete columns with a load of $60,000$ lbs per column; and

$$ the bottom of the mat will be at the ground surface $($i$.$e$.$ Df $=0).$

$1.)$

A$.)$Calculate settlement of the mat due to consolidation of the upper $100$ ft of the clay

layer. To do your calculation, divide the $100-$ft interval into $520-$ft thick sublayers and

calculate the consolidation settlement of each sublayer. The total settlement will be

the sum of the five calculated values. Use the Trapezoid Method to estimate stress

changes due to the mat load.