QUESTION 1 ned direct shear tests on a normally consolidated

QUESTION 1 ned direct shear tests on a normally consolidated dlay are shown in the table below. The diameter of the specimen is 05 in and the height is 2.5-inches, what is the normal stress for test specimen 27 Test number Normal Force Shear Force @ failure 267 400 489 556 166.8 244.6 311.4 355.8 Oa- 1,360 ps b. 1,812 psi O c 2,037 psi O d 2,491 ps

Solution

1)

Option C is correct.

Normal stress= (normal force/Area)

= 400/(3.14*0.5*0.5/4)

=2037 psi

2)

Option D is correct.

Shear stress= (shear force/Area)

= 355.8/(3.14*0.5*0.5/4)

=1812 psi

3) shear stress= C+normal stree * tan(45+phi/2)

166.8=0+267*tan(45+phi/2)

so, phi = 32

Option c is correct.