Relative density of cohesionless soils is defined as the ratio of the difference between the void ratio of a cohesion- less soil in the loosest state and in-situ void ratio to the difference between its void ratios in the loosest and the densest states. Thus relative density (Dr), also called density index (Id), is defined by – Dr = [(emax [...]
There are two basic methods of determining specific gravity of soils: 1. Pycnometer method 2. Density bottle method. 1. Pycnometer Method: Pycnometer method is used to determine the specific gravity of coarse-grained soils. Apparatus: In this method, a pycnometer of 900-mL capacity is used for determination of specific gravity. However, IS – 2720 (Part 3/sec 2) – 1980 recommends the [...]
Clay minerals in soils can be identified using one or more of the following methods: 1. X-ray diffraction (XRD) 2. Differential thermal analysis (DTA) 3. Transmission electron microscopy 4. Scanning electron microscopy 5. Infrared spectroscopy. Method # 1. X-Ray Diffraction: X-ray diffraction (XRD) technique is one of the most commonly used methods to identify the minerals present in a soil, [...]