Mechanical and Microstructure Characterization of Alccofine Based High Strength Concrete

Abstract

This study presents the influence of alccofine-1203 (alccofine) on mechanical and microstructure characteristics of High Strength Concrete (HSC). A total of 7 binder proportions were developed to evaluate the Standard Consistency (SC), Initial Setting Time (IST) and Final Setting Time (FST) of the binders, and mechanical properties of HSC. Scanning electron microscopic (SEM), energy dispersive X-ray spectroscopy analysis (EDS), X-ray diffraction (XRD) were used to study the microstructure characteristics of binder pastes. 4–14% of alccofine is used to replace cement form control mix. The test results showed that compared to control mix binder, the increase in alccofine replacement levels increased the SC slightly, but decreased the IST and FST. As alccofine replacement levels increased from 4 to 10%, the compressive and tensile strengths of concrete increased but 12 and 14% replacement levels reduced the strength of the concrete. Compared to the control mix, all the alccofine based mixes exhibited higher compressive and tensile strengths. SEM and EDS analysis demonstrated that compared to all other mix binders, mix with 10% alccofine had higher amount of C-S-H gel formation, stronger dense matrix with fewer pores and microcracks as well as low Ca/Si ratio. XRD analysis showed that mix with 10% alccofine revealed higher quantification of Alites and Larnites leading to higher early as well as later strengths to the M-10%AF mix compared to other mixes.