APPLICATION OF GEOTEXTILES IN PAVEMENT

The production of Portland cement has been swelling manifold throughout the world due to the mounting demands of the construction industry. However, this huge production of Portland cement is highly internal - energy - intensive and causes emission of green h ouse gas, CO2. The pollution involved in the manufacture of cement hampers the image of concrete as a sustainable material. Efforts are continuously being made to make concrete environmentally friendly. Concrete is the most commonly used construction mater ial without proper substitute so far. With the increase in construction activities, there is heavy demand on its ingredients, particularly for cement. Many such alternates for cement have been tried by different scientists worldwide, but the best choice of a substitute material to cement has been agreed to be the Geopolymer paste. Also, cement is manufactured by the calcinations process of a hefty quantity of lime stone and this large quantity of lime stone is explored from the lime quarries, which in turn creates an imbalance in the mineral wealth of our planet. In spite of the easy availability of Portland cement in the market at present, concrete made out of it is found to be less durable in some of the very severe environmental conditions due to the pres ence of free calcium. Therefore, arrival of any new alternate material of construction immediately should be assessed for both strength and durability. The complex phenomenon of aggressive chemical attack and the associated damage to concrete considerably reduces the strength and stiffness of reinforced concrete members leading to premature failure. Failure does not only mean structural collapse but also includes loss of serviceability characterized by cracking, spelling, deboning or excessive deflection. K eeping all the above aspects in mind, a detailed experimental investigation on the manufacturing process, serviceability under loads, durability against various severe disturbing agents are inevitable as far as a new material is concerned. Geopolymer concr ete is a firsthand development in the world of concrete in which cement is wholly replaced. Geopolymer concrete is a versatile and embryonic material in the construction industry. In this regard, Geopolymer concrete can be considered as a potential candida te material to replace cement concrete which does not generally have free lime which attributes an inherited property of acid resistance. Geopolymers are ceramic materials that are produced by alkali activation of alumina - silicate raw materials, which are transformed into reaction products by polymerization in a high pH environment and hydro thermal conditions at relatively low temperatures. As relatively new material, extensive studies are still needed to explore its applicability as a construction materia l. In this research, anthracite coal burnt low calcium fly ash from Tuticorin Thermal Power Station, Tamilnadu, India has been used to synthesize Geopolymer concrete. This work is state - of - the - art and the first of its kind in India to evaluate the applicab ility of Indian fly ash in Geopolymer concrete as source material for manufacturing alumina - silicate concrete under heat curing, with the aid of an exclusively designed Heat - curing chamber in the Geopolymer concrete laboratory of Thiagarajar College of Eng ineering, Madurai, Tamilnadu, India.