Geotechnical Engineering

 👉Casagrande apparatus: used to determine liquid limit.

👉 Oedometer is used to find the consolidation characteristic of soil.

👉 Hydrometer is used to determine grain size distribution

👉 Plate load test is used to determine safe bearing capacity of soil.

👉Pycnometer method is the laboratory method for determining specific gravity as well as water content of soil sample

👉Permeameter is used to find hydraulic conductivity and permeability of soil sample.

👉Core cutter is a field method to compute bulk density of soil.

👉 Increasing order of their grain size:

         Montmorillonite < Illite < Kaolinite

👉Sequence of plasticity index

    Montmorillonite > Illite > Kaolinite

👉 Relative compaction: Degree of compaction achieved as a percentage of the laboratory compaction

       Relative compaction = dry density in field/ maximum dry density from the proctor test 

👉Relative density can be zero but relative compaction can never be zero.

👉with increase in temperature, viscosity decreases and permeability increases.

                     k ∝ Unit weight/ Viscosity

👉Effective stress increases, void ratio decreases and permeability decreases.

 👉Organic matter has the tendency to move towards flow channel and choke them, thus reduces permeability

👉 Entrapped air decreases the permeability of soil.