Influence of singular and binary nanomaterials on the physical,mechanical and durability properties of mortars subjected to elevated temperatures and freeze-thaw cycles

摘要

In this paper, the singular and binary nanomaterials (halloysite nano-clay, nano-CaO and nano-SiO2) as a part replacement of cement were used to enhance the properties of mortars subjected to the elevated temperatures and freeze-thaw cycles. The mechanical and physical tests of the mortar were examined. Moreover, the microstructures and pore volume of samples after freeze-thaw cycles were examined by Scanning Electron Microscopy (SEM) and Barrett-Joyner-Halenda (BJH) technique. As a result, the highest compressive strength has been obtained with 3% halloysite nano-clay after durability effects. For the binary mixtures, the highest compressive strength is related to nano-CaO (2.5%) + halloysite nano-clay (2.5%) after freeze-thaw cycles. At elevated temperatures, the strength loss of mortar with nanomaterials are usually lower than control samples. The strength loss of the combination of nanoCaO and nano-SiO2 after durability effects is lower than the others. (C) 2021 Elsevier Ltd. All rights reserved.