GATE Civil Engineering (CE) 2020 Shift 1 Solved Paper

Question : 30 of 65

Marks: +1, -0

In a drained triaxial compression test, a sample of sand fails at deviator stress of

150 {kPa}

under confining pressure of

50 {kPa}

. The angle of internal friction (in degree, round off to the nearest integer) of the sample is

Solution:

σ_{3}=50

σ_{1}=200(50+150)

We know that

σ_{1}=σ_{3}(\;{1+\sin φ}/{1-\sin φ})+2 C √{\;{1+\sin φ}/{1-\sin φ}}

For sand

{C}=0

200=50(\;{1+\sin φ}/{1-\sin φ})

4=\;{1+\sin φ}/{1-\sin φ}

4-4 \sin ϕ=1+\sin ϕ

5 \sin ϕ=3

φ=\sin ^{-1}(\;{3}/{5})

φ=36.86^{∘}

Go to Question:

Prev Question

Next Question