Shear strength of soil

The shear strength of soil or rock is the maximum resistance that can be mobilized against shear stress. For soils this is not a constant value. It can vary with depth below the surface, with water content, and of course with methods used for stabilization. The shear strength of soil is small, compared to other materials such as steel or concrete, yet it is the major structural property of soils. It is this property which provides supporting ability and bearing capacity, and permits slopes to be stable. 

The shear strength of soil is made up of two separate components, cohesion and internal friction. Cohesion is related to grain size, and is apparent in clayey soils. Granular soils are not cohesive. Coulomb s equation is universally used to express shear strength ... 

Ko, H.Y., and Sture, S. 1981. State of the Art Data reduction and application for analytical modeling. In Symposium on Laboratory Shear Strength of Soil. ASTM STP 740. Yong, R.N., and Townsend, EC., eds., American Society for Testing and Materials, Philadelphia, PA, pp. 329-386. 

Castro, G. and Christian, J.T. 1976. Shear strength of soils and cyclic loading. Journal of the Geotechnical Engineering Division 102/9. ASCE 887-894. 

Koutsoftas, D.C. 1981. Undrained soil shear behavior of a marine clay. In Laboratory Shear Strength of Soil. ASTM STP 740. ed. R.N. Yong, and F.C. Townsend. ASTM. Philadelphia, PA 254-276. 

The vane technique has its origins as a method for in situ measurements of the shear strength of soils and an important assumption in the method is that the yielding surface that results from the vane s rotation is cylindrical, and of the same diameter as the vane (corrections can be made at a later stage if this is proven otherwise but they are difficult to assess for opaque materials). This assumption dictates that the material between the blades acts as a solid cylinder of dimensions equal to those of the vane, and the issue of the yield smface of visco-elastic and plastic fluids in a vane-viscometer has been addressed in several studies (e.g. see Yan and James, 1997 Keentok et al., 1985). 

The cusp method of F-rcurve needed the accurate shear strength, but the accurate shear strength of soil was difficult to be obtained in practice. So, another quantity with same physical meaning to t must be found. 

Introduction to shear strength of soils. Shear strength and stress-strain relationships in sands and... 

The Finn-Wu finite element procedure is simple and well suitable for practical engineering analysis. This analysis method adopts Mohr-Coulomb criteria for modeling shear strength of soils and uses a nonlinear hyperbolic model to simulate hysteresis response of soils under cyclic... 

ASTM D5321 Standard Test Method for Determining the Shear Strength of Soil— Geosynthetic and Geosynthetic—Geosynthetic Interfaces by Direct Shear... 

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