Shear Strength Test of Soil The choice of appropriate shear strength tests for a particular project depends on the soil type, whether the parameters will be used in a total or effective stress analysis, and the relative importance of the structure. Common laboratory tests include direct shear, triaxial, unconfined compression, and laboratory vane shear test. … Read more
Types of Soil Shear Test Based on Drainage Condition The shear strength parameters in the case of saturated soils depend very much upon the drainage conditions and therefore in the laboratory shear test, the drainage condition expected in the field for a particular problem should be simulated. Based on drainage condition the shear tests are … Read more
Determination of Organic Matter in Soil Purpose: This test is performed to determine the organic content of soils. The organic content is the ratio, expressed as a percentage, of the mass of organic matter in a given mass of soil to the mass of the dry soil solids. Standard Reference: ASTM D 2974 – Standard … Read more
Relative Density or Density Index Test of Sand Purpose: This lab is performed to determine the relative density of cohesionless, free-draining soils using a vibrating table. The relative density of a soil is the ratio, expressed as a percentage, of the difference between the maximum index void ratio and the field void ratio of a … 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
How to Classify Soil Visually on site? Purpose: Visually classify the soils. Standard Reference: ASTM D 2488 – Standard Practice for Description and Identification of Soils (Visual – Manual Procedure) Significance: The first step in any geotechnical engineering project is to identify and describe the subsoil condition. For example, as soon as a ground is … Read more
Unconfined Compressive Strength Test of Soil Purpose The primary purpose of this test is to determine the unconfined compressive strength, which is then used to calculate the unconsolidated undrained shear strength of the clay under unconfined conditions. According to the ASTM standard, the unconfined compressive strength (qu) is defined as the compressive stress at which … Read more
Constant Head Permeability Test of Sandy Soil Purpose: The purpose of this test is to determine the permeability (hydraulic conductivity) of a sandy soil by the constant head test method. There are two general types of permeability test methods that are routinely performed in the laboratory: The constant head test method, and (2) the falling … Read more
In geotechnical engineering, hydrometer analysis is primarily used to know the grain size distribution of a fine grained soil. In this post I will share with you the following things. What is a hydrometer? Why hydrometer analysis is done? What is the theory behind hydrometer analysis of soil? How to perform hydrometer analysis of soil? … Read more
Theory of Soil Compaction During compaction the reduction in volume is mainly due to expulsion of pore air and rearrangement of particles resulting in their closer packing. Compaction of a soil mass results in increase in dry density. The dry density attained depends on water content, amount and type of compaction. The amount and type … Read more