Different Forms of Bitumen 1. Cutback Bitumen Normal practice is to heat bitumen to reduce its viscosity. In some situations preference is given to use liquid binders such as cutback bitumen. In cutback bitumen suitable solvent is used to lower the viscosity of the bitumen. From the environmental point of view also cutback bitumen is … 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
Popping and Pitting Test of Lime Objective To determine popping and pitting of lime sample as per IS-6932-part-10 Theory This test is a measure to study the unsoundness of building limes. Popping, pitting and blowing are due to the presence of coarse unslaked or only partially slaked particles. On final slaking, these cause dislodgement of … Read more
Some Issues in the Usage of Fe- 500 or Higher Grade TMT Steel Bars in Residential Buildings Some contractors report a tendency among few design Engineers to specify Fe-500 or higher grade steel in residential buildings citing its high strength. Customers are advised that if they use Fe 500 or higher grade steel in building … Read more
Impurities in Sand Clay, silt, salts, mica and organic matter are a source of impurities in sand. All sands are generally found to contain some percentage of silt and clay. Mica is easily discernible from its shining surface. A certain percentage of impurities are inevitable in sand; a maximum of 6 % of silt and … Read more
Quality Requirements of Drinking Water Parameter Requirements (Desirable Limits) Undesirable effect when outside permissible limit Permissible limit in the absence of alternate source ESSENTIAL CHARACTERISTIC pH 6.5 – 8.5 Beyond this range the water will affect the mucous membrane and/or water supply system No relaxation Colour (Hazen units), maximum 6.5 – 8.5 Above 5, consumer … Read more
ABSOLUTE VISCOSITY TEST OF BITUMEN Reference IS: 1206 (Part 2) – Method for Testing Tar and Bitumen Materials: Determination of Absolute Viscosity Test Equipment The following testing equipment is needed to measure absolute viscosity of viscosity graded paving bitumen (IS:73-2006) at 60 C in accordance with IS:1206 (Part 2) (similar to ASTM D 2171), which … Read more
Definition – What is Bitumen Emulsion? Bitumen emulsion is a mixture of water & bitumen. Hey wait, we know that bitumen is a oil product and it cannot be mixed with water. That is why we add an emulsifier (a surface active agent) with water before adding bitumen. Addition of emulsifier with water facilitates breaking … 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