Strength and Durability Properties of Geopolymer Concrete Using Recycled Aggregates and QSD Under Acidic Environment

T. Ahalya, H. Sudharshan Rao and Vaishali G. Ghorpade

Engineers are venturing for high gauged reliably efficacious materials in tailoring significant real works. As a result, in every part of the world, ordinary Portland cement stands as a typical orthodoxy and a primary binder to instigate concrete. Also, the environmental concern over the manufacturing of OPC is on a serious note. The quantity of co2 that gets liberated in calcination process of limestone and fuel combustion is about 1 ton for 1ton OPC production in the environment. To contrast greenhouse gas emissions, an attempt is made in producing environmentally friendly building materials. This paper presents the evolution of fly ash based Geopolymer concrete which is a byproduct of silica and aluminum. The low calcium fly ash is chemically energized by high alkaline solution NaOH with 12M, sodium silicate to produce a paste which cohere the coarse aggregates , fine aggregate and additional materials in the concrete mix. Natural sand is a key material in producing concrete and plays a prominent role in Mix design. Whereas, River erosion and other environmental concern leads to lack of sand. Therefore, an alternative material which replaces the sand is selected as Quarry stone dust (QSD) which is a by-product acquired during quarrying. Despite there is a natural aggregates, the accessibility of Recycled Coarse Aggregate (RCA) available from demolished concrete fulfills as substitute material and trails had been made for different percentages of RCA over natural aggregates. An attempt has been made with the help of standard size cylinders (100*200) which were casted with 100% fly ash and tested to evaluate the mechanical characteristics such as tensile strength for a span of 28 days and also held durability tests such as acid resistant test using H2SO4 with 5% concentration for a span of 30, 60, 90 days for (12M) molarity of NaOH.

Volume 11 | 04-Special Issue

Pages: 669-676