Active and Passive Pressure
The active state occurs when a soil mass is allowed to relax or move outward to the point of reaching the limiting strength of the soil; that is, the soil is at the failure condition in extension. Thus it is the minimum lateral soil pressure that may be exerted. Conversely, the passive state occurs when a soil mass is externally forced to the limiting strength (that is, failure) of the soil in compression. It is the maximum lateral soil pressure that may be exerted. Thus active and passive pressures define the minimum and maximum possible pressures respectively that may be exerted in a horizontal plane.
Read more about this topic: Lateral Earth Pressure
Famous quotes containing the words active, passive and/or pressure:
“The sense of an entailed disadvantage—the deformed foot doubtfully hidden by the shoe, makes a restlessly active spiritual yeast, and easily turns a self-centred, unloving nature into an Ishmaelite. But in the rarer sort, who presently see their own frustrated claim as one among a myriad, the inexorable sorrow takes the form of fellowship and makes the imagination tender.”
—George Eliot [Mary Ann (or Marian)
“To make oneself an object, to make oneself passive, is a very different thing from being a passive object.”
—Simone De Beauvoir (1908–1986)
“Today’s pressures on middle-class children to grow up fast begin in early childhood. Chief among them is the pressure for early intellectual attainment, deriving from a changed perception of precocity. Several decades ago precocity was looked upon with great suspicion. The child prodigy, it was thought, turned out to be a neurotic adult; thus the phrase “early ripe, early rot!””
—David Elkind (20th century)