الفهرس | Only 14 pages are availabe for public view |
Abstract The aim of this research is to apply the recent concrete technology represented by using nano materials and steel fibers to investigate if they can enhance the performance of LWAC and its structural behavior especially strength and ductility. To achieve this objective, the experimental program was planned to be performed on two phases. In Phase I, the properties of nine concrete mixes were determined in both fresh and hardened states.Two concrete mixes were used as control mixes (NWC, LWC) and three mixes were cast fractions with three different nano silica contents and other three mixes were cast fractions with three different steel fibers fractions. After determining the optimum percentages of both nano silica and steel fibers, the ninth mix was a cast fraction using these percentages of nano silica and steel fibers. At the end of Phase I, a microstructure study was performed to help in interpreting the test results. In Phase II, the structural behavior of five reinforced concrete beams, representing the main concrete types in the research, was studied. The results show that using only 1.0% nano silica with 0.5% steel fibers increased the compressive strength of LWAC by 30.8% and increased the reinforced LWAC beam capacity by 19.3%and improved its microstructure and structural behavior |