Paper Title
Compatibility Of Chemical Admixture With Cement: Marsh Cone Test

In order to meet the performance requirements of concrete for various infrastructure projects, concrete mixtures have to be designed and produced using combination of different cementitious materials with water and aggregate and chemical admixtures. The active constituent of concrete is cement paste and largely it determines the performance of concrete. Admixtures in concrete confer some beneficial effects such as air entrainment, water reduction, plasticity, etc. on the cement paste. Also setting time acceleration / retardation can be achieved by the use of admixtures. Addition of some particular admixture may develop undesirable interaction between varying ingredients of concrete. Many times addition of admixture beyond certain limit may show incompatibility. The term “incompatibility” has been applied to various types of abnormal performance characteristics of concrete in both plastic and hardened stages, including setting and strength gain issues, excessive slump losses and increased water demand. Marsh cone test is used to formulate the optimum dose of particular admixture to the cement thereby avoiding cement-admixture incompatibility. For high Strength concrete and high performance concrete, depending on location i.e. distance of site from the plant, the retention time of the concrete plays important role. Because of retention time, the workability of concrete mix is increased as well as other properties like flowability, setting time of concrete is enhanced. Keywords— Compatibility, Marsh cone Time, Retention time, saturation point.