Geotech II: Chapter 12 Quiz Questions

True or False: The SHEAR STRENGTH of a soil mass is the internal resistance per unit area that the soil mass can offer to resist failure and sliding along any plane inside it.

Who presented a theory for rupture in material that contended that a material fails because of a critical combination of normal stress and shearing stress and not from either maximum normal or shear stress alone.

[blank_start]c[blank_end] represents the cohesion of the soil in terms of normal stress, and [blank_start]c'[blank_end] represents the cohesion of the soil in terms of effective stress. The value of c or c' for [blank_start]sand and inorganic silt[blank_end] is 0. For normally consolidated clay c' be approximated at [blank_start]0[blank_end]. Over-consolidated clay have values of c' greater than 0.

The angle of friction (phi') is sometimes referred to as the drained angle of friction.

Look at the figure below. Indicate whether the following points (A, B, and C) have failed or not.

Select the two most commonly used techniques for determining the shear strength parameters of soil:

True or False: The picture below shows the Direct Shear Test?

True or False: In dense sand, the peak shear strength and ultimate shear strength are the same values.

True or False: The drained angle of friction (phi') of normally consolidated clay generally decreases with the plasticity index of soil.

Select the shortcomings of the Direct Shear Test:

Select the following general types of triaxial shear tests that are conducted to determine the shear strength parameters of soil:

Label which deviator stress and volume change plots correspond to triaxial-stress tests on loose sand/normally consolidated clay and dense sand/over consolidated clay.

True or False: The Consolidated Drained type of triaxial test is uncommon for clayey soils.

The [blank_start]consolidated-undrained test[blank_end] is the most common type of triaxial test.

True or False: The Unconsolidated-Undrained Triaxial Test is usually conducted on clay specimens and depends on a very important strength concept for cohesive soils if the soil is fully saturated.