Describe how the unified soil classification system is used

Question

Question 1:

a. Describe how the Unified Soil Classification system is used to classify a soil sample as a clay with low plasticity CL. Indicate the suitability of a CL soil for engineering purposes.

b. Use the piston-spring analogy to explain how pore pressure affects the shear strength of soils.

c. Distinguish between peak stress and ultimate stress in soil tests and discuss which of these stress values obtained from tests should be used in design.

Question 2:

a. Sketch, interpret and explain in detail a typical graph of BOTH horizontal force vs horizontal displacement AND vertical displacement vs horizontal displacement obtained from a Direct Shear test of dense packed sand.

b. Explain in detail how soil compaction tests are used to set specifications for soil compaction. Identify and explain the factors that affect soil compaction.

Answer 1

For this assignment, you have to write answer for each part of the following two questions in an appropriate manner. Question 1: a) Illustrate how the Unified Soil Classification system is employed to categorize a soil sample as clay by means of low plasticity CL. Point out the suitability of a CL soil for engineering aims. b) Make use of the piston-spring analogy to describe how pore pressure influences the shear strength of soils. c) Differentiate between the peak stress and ultimate stress in soil tests and illustrate which of such stress values obtained from tests should be employed in design. Question 2: a) Sketch, interpret and describe in detail a typical graph of both horizontal force versus horizontal displacement and vertical displacement versus horizontal displacement obtained from the direct Shear test of dense packed sand. b) Describe in detail how soil compaction tests are employed to set specifications for the soil compaction.