Answer:
39⁰
Step-by-step explanation:
We have cohesion c = 25kpa
Then the normal stress = 39kpa
Shear stress = 56kpa
This question is asking us to find the angle of internal friction
Shear stress at the time of failure = cohesion C + normal stresstanΦ
56 = 25 + 39tanΦ
Φ = angle if refractive index
Φ = 38.48⁰
This is approximately 39⁰
Therefore in answer to this question, the angle of internal friction for the soil is nearly 39⁰
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