Soil Mechanics Test Questions &
Answers
secondary consolidation settlement Correct Ans-observed in saturated cohesive soils and is
the result of the plastic adjustment of soil fabrics. additional form of compression that occurs at
constant effective stress
oedometer Correct Ans-one-dimensional consolidation test, where soils sample is placed
under water between two porous stones loading it for 24 hours with different load amounts
OCR Correct Ans-overconsolidation ratio: preconsolidation pressure/present effective
vertical pressure
NC Correct Ans-normally consolidated clay - present effective overburden pressure is the
maximum pressure that the soil was subjected to in the past
OC Correct Ans-overconsolidated clay- present effective overburden pressure is less than
that which the soil experienced in the past.
preconsolidation pressure Correct Ans-maximum effective past pressure experienced by
overconsolidated clay
, 6 assumptions to find total settlement caused by primary consolidation Correct Ans-clay
water system homogeneous, saturation complete, compressibility of water negligible,
compressibility of soil grains negligible (but soil rearranges), flow of water is in one direction
only, Darcy's Law is valid
methods for accelerating consolidation settlement Correct Ans-sand drains, prefabricated
vertical drains in soft NC layers to achieve precompression before the consrutction of a desired
foundation
precompression Correct Ans-highly compressible, NC clayey soil layers lie at a limited depth
and large consolidation settlements are expected as a result, precompression minimizes
postconsruction settlement
shear strength Correct Ans-internal resistance per unit area that the soil mass can offer to
resist failure and sliding along an plane inside it
c' Correct Ans-cohesion
phi ' Correct Ans-friction angle
laboratory tests to determine shear strength Correct Ans-direct shear test, triaxial test,
direct simple shear test, plane strain triaxial test, torsional ring shear test
Answers
secondary consolidation settlement Correct Ans-observed in saturated cohesive soils and is
the result of the plastic adjustment of soil fabrics. additional form of compression that occurs at
constant effective stress
oedometer Correct Ans-one-dimensional consolidation test, where soils sample is placed
under water between two porous stones loading it for 24 hours with different load amounts
OCR Correct Ans-overconsolidation ratio: preconsolidation pressure/present effective
vertical pressure
NC Correct Ans-normally consolidated clay - present effective overburden pressure is the
maximum pressure that the soil was subjected to in the past
OC Correct Ans-overconsolidated clay- present effective overburden pressure is less than
that which the soil experienced in the past.
preconsolidation pressure Correct Ans-maximum effective past pressure experienced by
overconsolidated clay
, 6 assumptions to find total settlement caused by primary consolidation Correct Ans-clay
water system homogeneous, saturation complete, compressibility of water negligible,
compressibility of soil grains negligible (but soil rearranges), flow of water is in one direction
only, Darcy's Law is valid
methods for accelerating consolidation settlement Correct Ans-sand drains, prefabricated
vertical drains in soft NC layers to achieve precompression before the consrutction of a desired
foundation
precompression Correct Ans-highly compressible, NC clayey soil layers lie at a limited depth
and large consolidation settlements are expected as a result, precompression minimizes
postconsruction settlement
shear strength Correct Ans-internal resistance per unit area that the soil mass can offer to
resist failure and sliding along an plane inside it
c' Correct Ans-cohesion
phi ' Correct Ans-friction angle
laboratory tests to determine shear strength Correct Ans-direct shear test, triaxial test,
direct simple shear test, plane strain triaxial test, torsional ring shear test
