**Effective Stress**

Effective Stress is a force that keeps a collection of particles rigid. Usually this applies to sand, soil or gravel.

If you pinch a stack of coins between your fingers, the stack stays together. If you then loosen the pressure between your fingers, the coin stack falls apart. Similarly, a pile of sand keeps from spreading out like a liquid because the weight of the sand keeps the grains stuck together in their current arrangement, mostly out of static friction. This weight and pressure is the effective stress.

Effective stress is easy to disrupt by the application of additional forces; every footstep on a sand pile demonstrates this. It is an important factor in the study of slope stability and soil liquefaction, especially from earthquakes.

Read more about Effective Stress: Technical Discussion

### Other articles related to "effective stress, effective, stress":

**Effective Stress**- Technical Discussion

... Karl von Terzaghi first proposed the relationship for

**effective stress**in 1936 ... For him, the term ‘

**effective**’ meant the calculated

**stress**that was

**effective**in moving soil, or causing displacements ... It represents the average

**stress**carried by the soil skeleton ...

... distortions occur without any further changes in mean

**effective stress**, deviatoric

**stress**(or yield

**stress**, in uniaxial tension according to the von Mises ... The first equation determines the magnitude of the deviatoric

**stress**needed to keep the soil flowing continuously as the product of a frictional constant (capital ) and the mean ... particles will decrease as the logarithm of the mean

**effective stress**increases ...

... states that when a rock is subjected to a

**stress**, it is opposed by the fluid pressure of pores in the rock ... consolidation, states that all quantifiable changes in

**stress**to a soil are a direct result of a change in

**effective stress**... The

**effective stress**is related to total

**stress**and the pore pressure by the relationship reading that total

**stress**is equal to the sum of

**effective stress**and pore water ...

**Effective Stress**and Capillarity: Hydrostatic Conditions

... Although the pore air is relatively compressible, and hence takes little normal

**stress**in most geotechnical problems, liquid water is relatively incompressible and if the voids are ... The principle of

**effective stress**, introduced by Karl Terzaghi, states that the

**effective stress**σ' (i.e ... the average intergranular

**stress**between solid particles) may be calculated by a simple subtraction of the pore pressure from the total

**stress**where σ is the total

**stress**and u is ...

... (Terzaghi 1942) combined it with the principle of

**effective stress**... In terms of

**effective**stresses, the shear strength is often approximated by Where σ' =(σ - u), is defined as the

**effective stress**... σ is the total

**stress**applied normal to the shear plane, and u is the pore water pressure acting on the same plane ...

### Famous quotes containing the words stress and/or effective:

“A society which is clamoring for choice, which is filled with many articulate groups, each urging its own brand of salvation, its own variety of economic philosophy, will give each new generation no peace until all have chosen or gone under, unable to bear the conditions of choice. The *stress* is in our civilization.”

—Margaret Mead (1901–1978)

“I know no method to secure the repeal of bad or obnoxious laws so *effective* as their stringent execution.”

—Ulysses S. Grant (1822–1885)