Engineering Properties and Microstructural Performance of Low Energy Super-Sulfated Cement Using Industrial Waste Anhydrite

¹ Department of Civil and Construction Eng., National Taiwan University of Science and Technology (NTUST) (Taiwan Tech), Taipei, 106, Taiwan
² Department of Civil and Construction Eng., National Taiwan University of Science and Technology (NTUST) (Taiwan Tech), Taipei, 106, Taiwan
³ Department of Civil and Construction Eng., National Taiwan University of Science and Technology (NTUST) (Taiwan Tech), Taipei, 106, Taiwan
⁴ Department of Civil and Construction Eng., National Taiwan University of Science and Technology (NTUST) (Taiwan Tech), Taipei, 106, Taiwan
⁵ Department of Civil and Water Resources Engineering, National Chiayi University, Chiayi, Taiwan

^* Corresponding author, Department of Civil and Construction Engineering, Taiwan Tech, tpchang@mail.ntust.edu.tw
^a Corresponding author: author@e-mail.org

Abstract

This study aims at proposing the mix proportions of low energy super-sulfated cement (SSC) concrete from industrial waste anhydrite from circulating fluidized bed combustion (CFBC) fly ash (CFA) as an alternative sulfate activator of ground granulated blast furnace slag (GGBFS/slag). The optimized mix proportion of the SSC was carried out by using mixture of different amounts of CFA in range of 25—45 wt.% and various quantities of ordinary Portland cement (OPC) in range of 0 — 10 wt.% to trigger the hydration of slag. Experimental results showed that with the expected slump at values of 190 — 220 mm, the 28-day compressive strengths of the concrete with low energy SSC reached 43.69 MPa which can be feasibly applied for widely advanced construction materials. The OPC in range of 3 — 5 wt.% and 25 wt.% of CFA were considered as the optimum ingredients of the activator and was suggested to be used for fabricating the low energy SSC concrete with the good performance on compressive strength, dynamic Young’s modulus, UPV measurement, and stabilized change of length. The OPC additive up to 10 wt.% was encouraged to be used for producing the SSC concrete with significant reduction on creep.