Black Cotton Soil Black cotton soil has a tendency to shrink and swell excessively. When these type of soil come in contact with water, they swell and when becomes dry, it shrinks. This alternate process of swelling and shrinking results in the differential settlement of foundation which in turn causes cracks in building. The cracks … Read more
Deciding the right depth of foundation for a building structure is an important step in the process of building design. Information given in this post will help you decide the proper depth of foundation for a building. After reading this post you will be able to answer the following questions. What is a foundation? What … Read more
PLT (Plate Load Test) Plate load test is a field test which is commonly adopted to determine the bearing capacity and settlement of soil under a given condition of loading. In this test a square or circular rigid plate of standard dimension (generally 300 mm2 for square or 300 mm dia for circular) is placed … Read more
DCPT (Dynamic Cone Penetration Test) Dynamic cone penetration test or DCPT is a quick, simple and low cost test which is extensively used by many agencies around the globe to measure the strength of compacted material of unbound granular and sub grade layers with reasonable accuracy. Now a days DCPT is commonly used during construction … Read more
Laboratory Rules of Safety and Procedures The following safety regulations apply to all individuals engaged in testing as well as to those who even casually enter the concrete laboratory area: Rule-1 SMOKING— Strictly forbidden within any of the laboratory areas. Rule-2 CLOTHING—Everyone should provide themselves with suitable work clothes, of substantial quality, in good repair, … Read more
Different Test Methods for Workability Measurement Depending upon the water cement ratio in the concrete mix, the workability may be determined by the following three methods. Slump Test Compaction Factor Test Vee-bee Consistometer Test 1. Slump Test Suitability This method is suitable only for the concrete of high workability. This test is carried out with … 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
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
Types of Railway Yards The system of tracks laid usually on a fairly level ground for receiving, storing, sorting, making up trains and dispatch of vehicles, is known as railway yards. The railway yards are broadly classified as under Passenger yards Goods yards Marshalling yards Locomotive yards 1. Passenger Yards The main function of passenger … Read more
Sand Equivalent Value Test Purpose To determine the percent of undesirable particles in the fine aggregate fraction used in the design of Portland cement concrete mixtures. The method is also applicable for determining the relative proportions of detrimental fine dust or claylike material in soils. Equipment and Materials The Sand Equivalent test kit consists of … Read more