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The pressure exerted by soil against the wall is referred to as active pressure. The resistance offered by the soil to an object pushing against it is referred to as "passive pressure". Rankine's theory is applicable to incompressible soils. The equation for cohesionless active earth pressure is expressed as: = where:
The shear strength of soil depends on the effective stress, the drainage conditions, the density of the particles, the rate of strain, and the direction of the strain. For undrained, constant volume shearing, the Tresca theory may be used to predict the shear strength, but for drained conditions, the Mohr–Coulomb theory may be used.
An example of lateral earth pressure overturning a retaining wall. The lateral earth pressure is the pressure that soil exerts in the horizontal direction. It is important because it affects the consolidation behavior and strength of the soil and because it is considered in the design of geotechnical engineering structures such as retaining walls, basements, tunnels, deep foundations and ...
Most of the classical engineering materials follow this rule in at least a portion of their shear failure envelope. Generally the theory applies to materials for which the compressive strength far exceeds the tensile strength. [1] In geotechnical engineering it is used to define shear strength of soils and rocks at different effective stresses.
The Swedish Slip Circle method assumes that the friction angle of the soil or rock is equal to zero, i.e., = ′. In other words, when friction angle is considered to be zero, the effective stress term goes to zero, thus equating the shear strength to the cohesion parameter of the given soil.
The shear strength of soil is primarily due to interparticle friction and therefore, the shear resistance on a plane is approximately proportional to the effective normal stress on that plane. [3] The angle of internal friction is thus closely related to the maximum stable slope angle, often called the angle of repose.
Other advantages of the fall cone test include the alternative to estimate the undrained shear strength of a soil based on the fall cone factor K. [2] In the Fall cone test, a stainless steel cone of a standardized weight and tip angle is positioned so that its tip just touches a soil sample. The cone is released for a determined period of time ...
A direct shear test is a laboratory or field test used by geotechnical engineers to measure the shear strength properties of soil [1] [2] or rock [2] material, or of discontinuities in soil or rock masses. [2] [3] The U.S. and U.K. standards defining how the test should be performed are ASTM D 3080, AASHTO T236 and BS 1377-7:1990, respectively.