Question

What is difference between active and passive earth pressure?

Answer 1

Answer:

active earth pressure is one that is exerted by the soil and tends to overturn or slide the retaining wall

passive earth pressure is one that is exerted by the other side that tends to stabilize it. generally it is applied near the toe of the wall

Answer 2

Answer:

Active earth pressure is the one that is exerted by the soil that tends to overturn or slide the retaining wall. ... Passive earth pressure is the one exerted from the other side and that tends to stabilize it. Generally, it is applied near the "toe" of the wall.

Explanation:

When the retaining wall, due to load from the retained soil massive, which tends to slide down (wedge of failure), starts moving towards the soil in front of the wall (and thus off the retained soil), then the resting pressure from the retained soil becomes active pressure; while the pressure from the soil in front of the wall, resisting against the wall moving towards it, becomes passive pressure (displacement wedge pressure).