Durability of Bagasse Ash Based Cementitious Systems in Acidic Environment

Author(s): Ramaswamy K. P(1, 2), Satyanarayana Rao N(1) and Manu Santhanam(1)
Paper category: Proceedings
Book title: Proceedings of the 71st RILEM Annual Week & ICACMS 2017,Chennai,India, 3rd -8th September 2017
Editor(s): Manu Santhanam
Ravindra Gettu
Radhakrishna G. Pillai
Sunitha K. Nayar
ISBN: 978-2-35158-196-4
ISBN: 978-2-35158-190-2 (Set)
e-ISBN: 978-2-35158-191-9:
Publisher: Published by RILEM Publications S.A.R.L.
Publication year: 2017
Pages: 268-277
Total Pages: 10
Language : English

Abstract: One of the major causes of deterioration in cement systems is exposure to highly aggressive
acidic environments. The usage of sugarcane bagasse ash as a supplementary cementitious
material is proven to improve the mechanical and durability properties of the concrete.
However, the acid resistance of bagasse ash modified concrete is yet to be explored. In this
study, cement paste samples made with Ordinary Portland cement (OPC) and OPC with bagasse
ash (25% by mass) were exposed to mild concentrations of sulphuric and nitric acids. Mass
change and pH of the solution were analysed to understand the kinetics of degradation. X-ray
microtomography was used to evaluate the microstructural changes due to acid attack. The test
results show that accelerated leaching was observed in smaller prismatic specimens when
compared to cubical specimens of lesser surface area to volume ratio. Bagasse ash specimens
had more mass gain and expansion on exposure to sulphuric acid when compared to OPC at the
end of exposure period. The performance of bagasse ash mix was better for nitric acid exposure
as the mass loss observed was lesser. The zonation in the microstructure and altered depth was
evident from the tomography images.

Online publication : 2017
Publication type : full_text
Public price (Euros) : 0.00