Publication: Development of green quaternary binder high strength mortars Incorporating high volume of supplementary cementitious materials
Loading...
Date
2024-06
Authors
Ramzi J Abdussalam Shaladi
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The aim of this research is to develop a sustainable and practical quaternary binder high-strength green mortar (HSGM) and HSFRGM utilizing a high-volume replacement level (HVRL) of cement with supplementary cementitious materials (SCMs), namely ultra-fine treated palm oil fuel ash (u-TPOFA), metakaolin (MK), and ground granulated blast furnace slag (GGBFS) without compromising the initial engineering and durability properties. In order to find the ideal mix design, optimization of quaternary mixture (QOP) proportions, was carried out in this work using the Taguchi method L16 array. This QOP gives the highest compressive strength (CS) with the lowest porosity (P%) and water absorption (Abs%) at 3, 7, 14, and 28
days of water curing regime (normal curing, NCR). Further, a short and long-term evaluation of mechanical and fluid transport properties for the QOP and other HSGM mixtures (a total of 7 mortar mixtures) subjected to NCR, steam curing (SCR), and ambient curing (ACR) was undertaken. Finally, the short and long-term mechanical and fluid transport properties of the QOP mix were investigated with the inclusion of 2% of micro steel fiber (HSGFRM) by comparing with the control mix (100% ordinary Portland cement (OPC) incorporated with 2% of micro steel fiber - HSFRM). The
Taguchi method L16 results indicated the composition of QOP is 30% u-TPOFA, 15% MK, 17.5% GGBFS, and 37.5% OPC with a 0.25 water to binder ratio (W/B). This QOP shows a relative CS of 116.92% besides a decrease in both P% and Abs% compared to the control mix, with relative P% at 40.0% and relative Abs% around 45% at 28 days. The enhanced performance of the QOP mixture was proven and supported by TG and XRD analyses, undertaken to study the pozzolanic reaction kinetics. Furthermore, QOP performed better than the control mix and other HSGM binary mixes when subjected to NCR. It shows improved CS, flexural strength (FS), and splitting tensile strength (SpT) by 106.2, 12.7, and 7.9 MPa at 28 days and 116, 13.9, and 10.1 MPa at 90 days, respectively. Meanwhile, the lowest P%, Abs%, and rapid chloride permeability (RCPT) were realized in the QOP mix by 2.46%, 1.06%, and 132 coulombs at 28 days, and 2.11%, 0.92% and 63 Coulombs at 90 days, respectively. Moreover, the QOP mix showed better performance than the control mix and other HSGM mixes in all the curing regimes. The best curing regime for most HSGM mixes particularly QOP mix in terms of mechanical properties at 28 and 90 days is for samples subjected to NCR. Whereas the best curing regime in terms of fluid transport properties, is for mortar samples subjected to SCR. The superior performance was significantly achieved by the HSGFRM containing the QOP which was also confirmed by FESEM analysis. Therefore, the QOP mix has shown a sustainable and practical quaternary system of HSGM and HSFRGM productions at an HVRL of cement and still maintains the superior initial engineering and fluid transport properties.