Properties of calcium silicate-based inorganic phosphate cement at room controlled conditions. (1st April 2023)

• Record Type: Journal Article
• Authors: Ajoku, Chinedu A.; Turatsinze, Anaclet; Abou-Chakra, Ariane
• Is Part Of: Journal of building engineering. Volume 64(2023)
• Publication Date: 2023-04-01
• Subjects: Calcium phosphate cement -- Destructive and non-destructive methods -- Improved properties -- Strength evolution -- Sustainable cement; Building -- Periodicals; 690.05
• DOI: 10.1016/j.jobe.2022.105719
• Languages: English
• ISSNs: 2352-7102

Abstract

Abstract: Calcium phosphate cement (CPC) is a kind of chemically bonded phosphate cement that undergoes acid-base reaction to gain strength at room temperature conditions. The existing mix composition and methods previously proposed for making CPC are unsustainable. Two methods for producing more sustainable cement were employed in this research. These procedures involved the modification of the liquid/powder (L/P) ratio to use both less phosphoric acid and a simplified mixing approach complying with EN 196–1. First, the strength evolution of the phosphate cement was examined using destructive and non-destructive methods to determine the reference age to characterise the cement samples. This was found to be 14 days at room temperature of 20 o C and relative humidity of 65%. Then, the compressive strength, flexural strength, split tensile strength, density, mass loss, porosity and morphology of the cement were studied with respect to three parameters (L/P, type of mould and curing age) identified to have significant influence on their behaviour. It was established that the new techniques applied were adequate for manufacturing lightweight structural products with minimal environmental impact. Also, the use of an L/P ratio of 1.00, a non-airtight mould and an increased curing age favoured the formation of cement with improved properties. The overall behaviour of CPC was linked to the reaction rate in the fresh state of the material. Highlights: Sustainable techniques for making inorganic phosphate cement have been proposed. Destructive and non-destructive methods were adopted to study the strength progression of the cement, in addition to other properties. An environment-friendly lightweight structural cement has been produced for civil engineering applications. The property of the cement is influenced by its heat of hydration, which is directly affected by the liquid/powder ratio and mould type.