Durability and Mechanical Properties of Self-compacting Concretes with Combined Use of Aluminium Oxide Nanoparticles and Glass Fiber

The presence of fibers in concrete specimens has an effective role on how the specimens were failed. In this study, the effects of aluminium oxide nanoparticles on the workability, mechanical and, durability properties of SCCs containing glass fibers were investigated. Glass fibers contents of ۰, ۰.۵, ۱, and ۱.۵ % by volume of concrete and aluminium oxide nanoparticles contents of ۰, ۰.۵, ۱, ۱.۵, ۲, and ۳ % by weight of cement were used. The properties of fresh concrete were evaluated according to EFNARC consideartions. The mechanical properties were evaluated by compressive strength, splitting tensile strength, and ultrasonic pulse velocity tests. The durability of the specimens was also measured using water absorption tests, water penetration depth and, electrical resistivity. Combined use of ۲% aluminium oxide nanoparticles and ۱% glass fiber has increased the compressive and tensile strengths of SCCs by ۵۹% and ۱۱۹.۲%, respectively. Aluminium nanoparticles have a very high specific surface area and their reactivity causes them to react rapidly with calcium hydroxide to produce silicate-hydrate gels. Therefore, calcium hydroxide crystals are reduced and the cavities in the cement gel are filled and the compressive strength is increased. The use of aluminium oxide nanoparticles along with glass fibers reduces the water absorption rate compared to the sample without these materials. This is one of the effective properties of aluminium oxide nanoparticles, which increases the resistance to adverse environmental factors by reducing water absorption.

کلیدواژه ها:

Aluminium oxide nanoparticles ، Durability properties ، glass fiber ، Mechanical properties ، Rheological properties ، Self-ompacting Concrete