Atterberg limits and plasticity index in plain words
Liquid limit, plastic limit and shrinkage limit, what the plasticity index tells you, and how the A-line classifies fine soils.
Subject
Geotechnical Engineering
Soil mechanics, foundations, slopes and retaining walls.
Darcy's law and how permeability is measured
Flow of water through soil, the coefficient of permeability, and when to use the constant head or falling head test.
Shear strength of soil and the Mohr–Coulomb equation
What cohesion and friction angle mean, why effective stress controls strength, and which shear test to pick.
Soil compaction: Proctor test, OMC and maximum dry density
Why there is a best water content for compaction, how the compaction curve is drawn, and what the zero air voids line means.
Soil phase relations: void ratio, porosity, water content and unit weight
The three-phase soil diagram and the handful of relations, like Se = wG, that solve almost every phase problem.