Effects of Micro Silica & Flyash on Strength & Durability Parameters of High Strength Concrete

Abstract

High strength concrete is a term used to describe concrete with special properties not attributed to normal concrete. High-performance means that the concrete has one or more of the following properties: low shrinkage, low permeability, a high modulus of elasticity, or high strength. The application of nanotechnology in concrete has added a new dimension to the efforts to improve properties of High strength concrete. Nano materials, by virtue of their very small particle size can affect the concrete properties by altering the microstructure. Concrete can deteriorate for a variety of reasons, and concrete damage is often as result of combination of factors. This causes stresses in the concrete, which can eventually have resulted in cracking, delamination, and spalling. Concrete resists weathering action, chemical attack, and abrasion while maintaining its desired engineering properties throughout its lifespan. Different concretes require different degrees of durability depending on the exposure of environment and the properties desired. Durable concrete will retain its original form, quality and serviceability when exposed to its environment. The main characteristics influencing the durability of concrete is its permeability to the ingress of water, oxygen, carbon dioxide, chloride, sulphate and other deleterious substances. It became necessary to impart knowledge about durability of concrete and factors affecting durability to the society, as the wide use of concrete as a material in the constructions. This study concerns with the use of Nano silica of size 12 nm in M60 grade of concrete to improve the compressive strength of concrete and study on various durability parameters of High strength concrete. An experimental investigation is planned to carry out with different amount of Fly ash as 15% ,20%, 25%,30% and Micro silica as 5.5%,7%,8.5%,10% in concrete by weight of concrete. have been planned to carry out are workability, compressive test, flexural test, split tensile test. To study durability parameters of High strength concrete with nano silica Rapid chloride penetration test (RCPT), Water Sorptivity test, Acid attack test, Sulphate attack test are conduct. In this study it was observed that t the durability, strength and workability are increase as the percentage of fly ash & micro silica increses