Introduction:

1.1.      Definition(s) of Soil:

Civil Engineer’s definition of soil; Geologist definition of soil; Agriculturalist soil definition.

1.2.        Nature and Origin of Soil and Rocks:

Mineral content of soil; common types of soils: clay, silt, loamy soil, sand, gravel, etc.

            Engineering Properties of Soil:

2.1.        Volumetric Properties of Soil:Void ratio (e); porosity (n); degree of saturation (Sr).

2.2.        Densities and Water Contents of Soil:

2.2.1. Soil Densities: Density (e) and Unit weight ; Bulk unit weight and density; Dry unit weight and density, specific gravity of soil particle (Gs). Relative Density (R.D.) Relationship between unit weights and densities of soil.

 Laboratory test for moisture content; relationship between moisture content; density ; specific gravity , and degree of saturation ; cone penetration test.

            Consistency Limits or Index Tests of Soils:

Shrinkage Limit (SL); liquid limit (L. L) and liquidity index (IL.); plastic limit (P.L.) and plasticity index (PI.).

            Soil Classification (Grading):

                         General Basis for field identification and classification of soils.

                        Laboratory and in situ classification of soil.

                        Casagrande soil classification system (GW-SW)

          Particle size Distribution/Gradation: sieve analysis. Effective size (D10), uniformity coefficient (U.C.).

             Hydrometer Tests and Analysis for very fine soils.

            Shear Strength of Soils:

 

Laboratory testing for shear strength (shear box test); soil friction and cohesion; Coulomb’s Law of soil shear strength; pure pressure; Mohr’s circle diagram and principal plane for soil; soil strength envelopes.

            Soil Water, Permeability and Flow:

                       Flow of water through soils and Darcy’s Law; coefficient of permeability (K).

                        Relationship between permeability and other soil physical properties.


                        Graphical solution of seepage problems – Flow nets, Flow lines, equip of entail lines, Hydraulic gradient; seepage forces.

                        Earth Pressure:

Active and passive earth pressure; surcharge loads and overburden loads, etc. Retaining walls.

 


Level of Study: 300 Level