Q$-3(10$ Marks$)$

The results of two drained triaxial tests on a saturated clay are as follows:

Sample $1$:

${}_3=70k\frac{N}{m^2}$

and $P_f=130k\frac{N}{m^2}$

$U=20k\frac{N}{m^2}$

Sample $2$:

${}_3=160k\frac{N}{m^2}$

and $P_f=223\mathrm{.}5k\frac{N}{m^2}$

$U=50k\frac{N}{m^2}$

a$-$ Determine the strength parameters, total and effective $(C,)$

b$-$ Calculate the angle of shear failure plan $()$

c$-$ The shear strength at normal stress of $300k\frac{N}{m^2}$

Solve Graphically and by equations