QAQC in Construction

  Design Mix: This test helps in determining the suitable ingredients of concrete and determining their relative amounts with the objective of producing concrete of the required strength, durability, and workability as economical as possible is termed as concrete mix design. It involves studying properties of Aggregate, Cement, Water & Admixture (if any), and is used to determine the proper Concrete Mix Design. Ref: ACI 211.1 Ultrasonic Survey: Ultrasonic concrete testing is based on the pulse velocity method to provide information on the uniformity of concrete, cavities, cracks, and defects. The pulse velocity in a material is directly proportional to its density and its elastic properties which in turn depends on the compressive strength and the quality of the concrete. It is, therefore, feasible to obtain information about the properties of components by sonic investigations. Test Method: IS 13311 (Part 1) Chloride Content: Measuring the calcium chloride content of...

Aggregates are inert granular materials such as sand, gravel, or crushed stone that, along with water and portland cement, are an essential ingredient in concrete. For a good concrete mix, aggregates need to be clean, hard, strong particles free of absorbed chemicals or coatings of clay and other fine materials that could cause the deterioration of concrete. Aggregates, which account for 60 to 75 percent of the total volume of concrete, are divided into two distinct categories--fine and coarse. Fine aggregates generally consist of natural sand or crushed stone with most particles passing through a 3/8-inch sieve. Coarse aggregates are any particles greater than 0.19 inches but generally range between 3/8 and 1.5 inches in diameter. Gravels constitute the majority of coarse aggregate used in concrete with crushed stone making up most of the remainder. Natural gravel and sand are usually dug or dredged from a pit, river, lake, or seabed. Crushed aggregate is produced by crushing quarry r...