Concrete for water retention structureAuthor: Aritra Pal; Entry Number 2013CEC83141.0 Introduction: The aim of this study is to select a better choice of watertight concrete for waterproofing construction of water retention structures such as tanks, reservoirs, swimming pools, etc. . This article includes the study of the early age and subsequent aging properties of concretes with chemical admixtures and additional cementitious materials, from the point of view of watertightness and durability.2.0 Principle of watertightness water:• Concrete must be dense and durable• Concrete must have the ability to withstand hydrostatic pressure without water infiltration.• Concrete usually contains voids and cracks can occur due to external loads or internal thermal and shrinkage stresses, structural movements, etc. These gaps and cracks can become a pathway for water infiltration. • For cracks due to external loads, nothing can be done with the properties of concrete. but for internal shrinkage stress, good mix design is required with limited cement content, proper placement and curing. • Dense and durable concrete can be achieved by low water/cement ratio and for proper placing and curing, workability of concrete mix is ​​one of the important factors.• For high strength, low high permeability, durability and workability, the use of an admixture is recommended.3.0 Some properties to consider:• Permeability: Concrete is a mixture of cement and aggregates. Aggregates are generally dense materials so the permeability of the cement paste determines the waterproofness of the concrete. The gel pores in cement paste are very small, they generally do not affect the density, but the capillary pores with the micro and macro cracks can form the passage of water. Capi...... middle of paper ...... voids and microcracks can thus reduce permeability and increase water tightness.• The pozollanic reaction will convert very dense CSH with large cavities into a relatively low density CSH with smaller voids• These properties can increase the strength and durability of concrete.Permeability:• Due to the filling effect of SCM, the permeability of concrete will be decreased effectively.Durability:• Corrosion of steel: The low permeability of concrete prevents the penetration of chloride and thus reduces the risk of corrosion in the reinforcing steel. Due to the impermeability of concrete, carbon dioxide cannot penetrate the concrete and the risk of carbonation will be minimized, resulting in carbonation attack on the steel. be reduced.• Acidic environment: Due to the presence of a large amount of calcium hydroxide