Soil Mechanics

Select the incorrect statement. Effective angle of shearing resistance

• increases as the size of particles increases

• increases as the soil gradation im-proves

• is limited to a maximum value of 45 degrees

• is rarely more than 30 degrees for fine grained soil

In a triaxial compression test when drainage is allowed during the first stage (i.e. application of cell pressure) only and not during the second stage (i.e. application of deviator stress at constant cell pressure), the test is known as

• consolidated drained test

• consolidated undrained test

• unconsolidated drained test

• unconsolidated undrained test

These are materials that are derived from the weathering of rocks.

The original form of this system was proposed by Casagrande in 1942 for use in the air-field construction works undertaken by the Army Corps of Engineers during World War II. In cooperation with the U.S. Bureau of Reclamation, this system was revised in 1952. At present, it is used widely by engineers (ASTM Test Designation D-2487).

• MIT

• AASHTO

• USDA

• USCS

The total and effective stresses at a depth of 5m below the top level of water in a swimming pool are respectively

• zero and zero

• 0.5 kg/cm^2 and zero

• 0.5 kg/cm^2 and

  0.5 kg/cm^2

• 1.0 kg/cm^2 and

  0.5 kg/cm^2

The water content of soil, which represents the boundary between plastic state and liquid state, is knows as

• liquid limit

• plastic limit

• shrinkage limit

• plasticity index

The shear strength of a soil is ____

• is directly proportional to the angle of internal friction of the soil

• is inversely proportional to the angle of internal friction of the soil

• decreases with increase in normal stress

• decreases with decrease in normal stress

In a triaxial compression test when drainage is allowed during the first stage (i.e. application of cell pressure) only and not during the second stage (i.e. application of deviator stress at constant cell pressure), the test is known is

• consolidated drained test

• consolidated undrained test

• unconsolidated drained test

• unconsolidated undrained test

In the triaxial compression test, the application of additional axial stress (i.e. deviator stress) on the soil specimen produces shear stress on

• horizontal plane only

• vertical plane only

• both horizontal and vertical planes

• all planes except horizontal and vertical planes

Which of the following methods is most accurate for the determination of the water content of soil?

• oven drying method

• sand bath method

• calcium carbide method

• pycnometer method