Admixtures for Concrete and its type like chemical admixture & mineral admixture by Dr K Mohan 

Lecture-10: Admixtures for Concrete and its type like chemical admixture & mineral admixture by Dr K Mohan
Dr K Mohan is an internationally renowned and an acclaimed cement scientist. He is a former Director General of National Council for Cement and Building Materials (NCCBM).
He holds a Ph.D. degree in Cement Chemistry from University of Aberdeen, Scotland, U.K
Admixtures:
• Admixtures are the ingredients in concrete other than cement, water, and aggregates that are added to the concrete mix immediately before or during mixing to modify the properties of fresh or hardened concrete.
• They are added in small quantity either in powder or liquid form.
Major Reasons for Using Admixtures:
• To reduce the cost of concrete construction.
• To modify properties of fresh and hardened concrete.
• To maintain the quality of concrete during mixing, transporting, placing and curing in adverse weather conditions.
• To overcome certain emergencies during concreting operations.
Functions (Purposes) of Admixtures:
• To increase workability without increasing the w/c ratio or decreasing the water content.
• To retard or accelerate initial setting time.
• To reduce segregation and bleeding.
• To improve pumpability.
• To reduce heat of hydration.
• To accelerate the rate of strength development at early ages.
• To increase strength and durability of concrete.
• To decrease permeability of concrete.
• To control alkali aggregate reaction.
• To improve impact and abrasion resistance.
• To inhibit corrosion of steel.
Types of Admixtures:
• Chemical Admixtures
• Mineral Admixtures
#AdmixturesforConcrete #chemicaladmixture #MineralAdmixtures