Evaluating the physical and strength properties of fibre reinforced magnesium phosphate cement mortar considering mass loss

摘要

Fibre reinforced magnesium phosphate cement (FRMPC) composites are drawing attention day by day in the practical applications due to their excellent strength performance. Keeping this issue in mind, this study aimed to add a little contribution on this area by examining the physical and strength properties of FRMPC mortars containing micro-steel fibre (MSF), polyvinyl alcohol fibre (PVA) and basalt fibre (BF). Each fibre content with consecutive four dosages such as 0.6%, 0.8%, 1% and 1.2% of the total quantity of binders and aggregate, were added in the designated combinations. The analyzed results exhibited that porosity, pore degree of saturation, reduction of permeable voids, density and water absorption properties were well improved for adding 0.6% and 0.8% MSF and PVA, and 0.6% BF fibres in the matrices, whereas the rest two selected higher fibre contents made the microstructure of MPC specimens sponginess by forming the substantial quantity of internal pores. Mass loss was recorded about 0.6%-1% for air cured FRMPC samples at 28 d by adopting abrasion test, where the static immersion liquid condition revealed around 1.5% - 3.0%. In addition, air cured samples containing 0.8% MSF showed the highest compressive strength around 54.8 MPa and 82.6 MPa at 1hr and 28 d, respectively than other considered combinations. Moreover, FRMPC syntheses exposed around 10% - 15% strength loss in water environment as compared to air. SEM observations presented the well interfacial closeness of MSF by coating the hydration products that probably enhanced the noteworthy strength quality of MSF-MPC mortars. XRD investigations also corroborated the possible explanation for reducing the strength loss in water regime by presenting the low peaks of struvite minerals, which was happened due to the dissolution of mass that accorded with the experimental results. These findings might show a path for potential use of FRMPC specimens to enhance the durability properties. (C) 2019 Elsevier Ltd. All rights reserved.