I need help with this question as soon as possible, Please and Thank you! The qu
ID: 120580 • Letter: I
Question
I need help with this question as soon as possible, Please and Thank you!
The question asks:
Which statement best explains how moisture affects slope stability:
1. Small amounts of moisture make a slope stable because of cohesion, but saturated conditions create pore pressure which causes a slope to become unstable.
2. Small amounts of moisture make a slope stable because of pore pressure, but saturated conditions promote cohesion which causes a slope to become unstable.
3. Only dry materials are stable. Small amounts of moisture and saturated conditions create pore pressure which causes a slope to become unstable.
4. Only moist or wet materials are stable. Dry materials are always unstable.
Explanation / Answer
Q) Which statement best explains how moisture affects slope stability:
Ans. 1. Small amounts of moisture make a slope stable because of cohesion, but saturated conditions create pore pressure which causes a slope to become unstable.
In case of the slope stability analysis moisture is an important factor. Physical interaction among soil grains are strongly influenced by the water in soil. Moisture can changes the pore pressures which is directly impact the effective stresses, affect both the shear strength and consolidation behaviour of soil.
Small amounts of moisture make a slope stable because of cohesion. If you take a look on sand grains, the angle of repose is greater in case of wet sand than dry, upto a certain limit. In case of clay, small amount of moisture addition can cause adsorption, which increases the cohesion of the particles. But if there is addition of more water, the phemonan absorption happens, which causs minerals to take water into their structure. So, weight of the soil increased, which causes the slope to become unstable.