RECOVERY OF MECHANICAL PROPERTIES OF SELF HEALING CONCRETE USING SUPER ABSORBENT POLYMER (SAP)

This project is study of Self-healing behaviour of concrete which deals with mechanical properties of concrete is widely used to improve the durability of the concrete. Self-healing concrete is a product that will chemically produce hydrates to heal the cracks that appear on the surface of concrete structures. In self-healing process healing agent absorbs the moisture content present in atmosphere to heal. This process enhanced mechanical properties of concrete. Superabsorbent polymers (SAPs) are materials that have the ability to absorb and retain large volumes of water and aqueous solutions. SAP is now a mature product that has quickly progressed from specialty chemical to special commodity. Sodium silicate is used as SAP chemical admixtures as well as self-healing agent for concrete. Sodium silicate in liquid form at 2% is mixed with concrete based on previous work. As per IS 10262 : 2009, M40 grade concrete mix design is derived for both control and SAP concrete and specimens are prepared for compressive strength, split tensile strength and flexural strength. At age of 7, 14, and 28 and 56 days, tests are conducted to determine the compressive, split tensile and flexural strengths. The specimen are also pre-cracked on 28th day and re-cured for 28 days to undergo rapid self-healing process. On 56th day, they are tested for determining the recovery of strengths. The effect of 2% sodium silicate on the strength and the healing property of concrete is studied by determining the self-healing efficiency