Effect of alkaline activator on static and dynamic properties of geopolymer mortars containing ferrock and fibers

Articles in Press

Document Type : Original Article

Authors

• Seyed Hosein Ghasemzadeh Mousavinejad ¹
• Amir Hosein Varasteh ²

¹ Civil Engineering, Engineering Faculty member, university of Guilan

² civil engineering master student at university of Guilan

10.22067/jfcei.2025.88923.1312

Abstract

Cement is one of the most widely used construction materials in the world. Its production process is highly polluting and leads to the release of carbon dioxide (CO₂) into the atmosphere. In addition to CO₂ emissions, cement production generates millions of tons of kiln dust annually, causing respiratory health risks and environmental pollution. Ferrock, an innovative iron-based compound, is a carbon-free alternative to cement that utilizes industrial waste for a versatile construction material. Accordingly, this study investigated the effect of alkaline activators on the static and dynamic properties of geopolymer mortars containing ferrock and polypropylene fibers. The variables in this study included two liquid-to-binder ratios (0.4 and 0.5), two sodium silicate-to-sodium hydroxide ratios (1.5 and 2), various replacement percentages of ferrock (5%, 8%, 12%, and 15%), and polypropylene fibers (0.1%, 0.2%, 0.3%, and 0.5%) across three steps. The results showed that curing in ambient conditions performed better than water curing. Samples containing 8% ferrock and 0.1% fibers exhibited the best performance. The compressive strength of the samples after 28 days reached 75.2 MPa, and the flexural strength was recorded at 5.52 MPa. Furthermore, in the electrical resistivity test, a maximum value of 144.6 kΩ•cm was observed. The inclusion of fibers, even in small amounts, significantly improved impact resistance, with a maximum increase of 57% being observed. These findings demonstrate that the use of ferrock and polypropylene fibers is an effective strategy for enhancing the mechanical and environmental properties of construction mortars.

Keywords

• alkaline activator
• ferrock
• green cement
• geopolymer
• fibers

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