Effect of Silica Fume and Nano Silica on Mechanical Properties of Fiber-Reinforced Lightweight Concrete

Lightweight concrete has significant importance due to its special features including weight reduction of structures.This article aims to study ‎the effect of silica fume (SF) and ‎nano silica (Na) on mechanical properties of fiber reinforced concrete containing lightweight scoria aggregates. SF ‎and Na are replaced by different amounts of cement weight. The used amounts of Steel and ‎polypropylene fibers having different length to ‎diameter ratios are different.‎ For this study, seventeen different lightweight mixtures ‎were made and tested for mechanical strengths, water absorption and density. ‎Results show that optimized replacement ‎amount of SF and Na is 10% and 3%, respectively. Steel fiber in comparison to ‎Polypropylene fiber had‎ better effect on mechanical characteristics of lightweight concrete.‎