Situation $1-$ A square column is located at the center of a pile cap as shown in the figure.

Given:

$a=600mm,c=600mm$

$b=1200mm,d=1000mm$

Column dimension $=600mm600mm$

Pile dimension $=350mm350mm$

Effective depth $of$ the pile cap $=400mm$

Net ultimate axial load $=3240kN$

Net ultimate moment about the $Y-$axis $=360kN-m$

Concrete compressive strength, $f_c^{\text{'}}=20\mathrm{.}7$MPa

Steel yield strength, $f_y=413$MPa

Strength reduction factors:

Shear $=0\mathrm{.}75$

Moment $=0\mathrm{.}90$

$4.$ How much is the maximum beam shear stress $(MPa)$ in the pile cap?

A$.0\mathrm{.}75$

C$.1\mathrm{.}00$

B$.0\mathrm{.}96$

D$.1\mathrm{.}28$

$5.$ Compute the punching shear stress $(MPa)$ in column.

A$.3\mathrm{.}6$

C$.2\mathrm{.}4$

B$.1\mathrm{.}8$

D$.1\mathrm{.}2$

$6.$ Compute the punching shear stress $($ MPa in the most heavily loaded pile.

A$.0\mathrm{.}46$

C$.0\mathrm{.}34$

B$.0\mathrm{.}25$

D$.0\mathrm{.}42$

$7.$ Determine the required spacing $(mm)$ of the $20-$mm$-$diameter bars for the critical moment.

A$.156$

C$.198$

B$.112$

D$.232$