Investigation of Durability, Microstructural and Mechanical Characteristics of Polyethylene Glycol 400-Based Self-Curing Concrete

Abstract

Proper curing of concrete is crucial to ensure adequate moisture content and the development of desired strength. Inadequate curing can significantly affect the strength and durability of concrete, often leading to early cracks in buildings and subsequent strength reduction. Self curing concrete falls into the special concrete category, serving as a solution to address insufficient curing issues. various researchers have investigated the mechanical and durability properties of polyethylene glycol-based self-curing concrete in several ways. However, there was no relevant study on the polyethylene glycol- 400 self-curing concrete's cost-effectiveness and durability properties. In this regard this study aims to investigate the effects of incorporating polyethylene glycol-400 in self-curing concrete production. Factors such as workability, compressive strength, water absorption, sulfate attack, and microstructure, along with cost implications, were analysed. To develop the concrete mix for C-30 concrete grade, the American Concrete Institute's mix design method was employed. The study consisted of producing two mixes: a control mix made up of cement, water, fine and coarse aggregate, and involved varying the percentage of polyethylene glycol -400 (1%, 1.5%, 2%, 2.5%, and 3%) by the weight of cement added to the mixing water. As the polyethylene glycol -400 content increased in the concrete mix, the workability of the concrete increases due to the incensement of fluidity of the mix. However, the compressive strength at 28 days of curing saw a 20.39% improvement for the 2% mix compared to the control mix. The cause of the increase in the compressive strength of the concrete was due to the creation of more Calcium Silicate Hydrate gel. Therefore, a 2% mix showed the best results in terms of compressive strength. Moreover, the pores inside the concrete matrix were filled due to Calcium Silicate Hydrate (C-S-H) gel formation, leading to lower water absorption in the concrete with a 2% mix. Furthermore, adding polyethylene glycol-400 to concrete mix was improved the sulfate attack resistance of the self-curing concrete. The self-curing concrete was analysed microstructurally and compared to the control mix. The study found that the mix with a 2% had more calcium silicate hydrate gels. The study concluded that by utilizing polyethylene glycol-400 up to 2%, the compressive strength of self-curing concrete can be improved while also lowering the cost of the curing procedure of concrete