WEIGHT VOLUME RELATIONSHIP OF SOIL The physical properties of a soil give insight as to the identification of the soil and the determination of its characteristics and load response. These properties can be determined by performing a laboratory analysis on undisturbed soil samples obtained during the test boring process. The laboratory analysis should be performed … Read more
How to Select Soil & Rock Properties for Engineering Design? A rational approach for selecting soil & rock properties for engineering design can be summarized as a logical twelve-step procedure that covers the 3 primary stages i.e. Site Investigation and Field Testing, Laboratory Testing and Interpretation, and Engineering Design This step-by-step process is presented on … Read more
Geo-technical Engineering Terms Absorbed water Water held mechanically (by surface tension) in a soil mass Activity Ratio of the plasticity index to the clay fraction Adhesion Shearing resistance between soil and another material under zero externally applied pressure Adsorbed water Water in a soil mass, held by physio-chemical forces, having physical properties are substantially different … Read more
Measurement of Soil Compaction in the Field It is necessary in many instances to know the wet/dry densities of the soil in the field, especially before planning activities such as compaction. The same becomes particularly important in instances such as the construction of earth dams, embankments etc. to control the field compaction, that is, to … Read more
Moisture content – Dry Density Relationship At a given input of compaction energy there exists a relationship between moisture content or water content and dry density, which is of the form shown in Fig-1. On the dry side, the added water creates a coating of a thin film of water on the surface of the … Read more
Density Test of Soil Purpose: This lab is performed to determine the in-place density of undisturbed soil obtained by pushing or drilling a thin-walled cylinder. The bulk density is the ratio of mass of moist soil to the volume of the soil sample, and the dry density is the ratio of the mass of the … Read more
SOIL STRUCTURE / SOIL FABRIC The term soil structure in general, refers to the arrangement or state of aggregation of particles in a soil mass. But deeper understanding of soil structure demands consideration of mineralogical composition, shape and orientation of soil particles; the nature and properties of soil water, and the forces of interaction between … Read more
On earth retaining structures such as retaining wall, sheet piles, etc, the back fill retained mass of soil, exerts lateral pressure known as earth pressure. If the positions of the back fill lies above a horizontal plane at the elevation of the top of the structure, it is called surcharge. The inclination of the surcharge … Read more
Components Contributing Settlement of Soil Total settlement ρ in mm, which is the response of stress applied to the soil, may be calculated as the sum of three components ρ = ρi + ρc + ρs Where, ρ = Total settlement, mm ρi = Immediate or distortion settlement, mm ρc = Primary consolidation settlement, mm … Read more
Engineering Properties of Soil The following properties of soil are taken into consideration while dealing with soil as a construction material. Cohesion Angle of internal friction Capillarity Permeability Elasticity Compressibility 1. Cohesion It is the internal molecular attraction which resists the rupture or shear of a material. Cohesion is derived in the fine grained soils … Read more