Q$.8$ Suppose that the self$-$balanced strain due to shrinkage for a circular$-$ shaped beam $(150500mm)$ along the diameter direction follows the distribution of $=0\mathrm{.}00016(\frac{x}{R}{)}^2-0\mathrm{.}0001,$ where $R$ is the radius of the circular shape. The $E_c=20$GPa. If the peak load, $P,$ for this beam under pure bending is $6600N,$ calculate the tensile strength for the concrete by eliminating the effect of shrinkage. The self$-$weight of the beam can be ignored in this problem.