Performance of nano-Silica modified high strength concrete at elevated temperatures

This research studied effect of elevated temperature on of high strength concrete (HSC) modified with nano-Silica (nS) and on its compressive and tensile strengths, spalling, and mass loss (f′c > 80 MPa). This research studied the effect of elevated temperature on the compressive and tensile strength, spalling, and mass loss of HSC modified with nS. Six sample mixtures contained varying amounts of nS and two samples did not contain nS are considered in the experimental program. The mechanical properties of the modified HSC were measured by heating 150 × 300 mm sample cylinders of concrete to 400, 600 and 800 °C at a rate of 20 °C/min. The obtained results demonstrate that nS efficiently used in HSC can improve its mechanical properties at elevated temperature. The results show that the presence of nS increased residual compressive and tensile strengths, and spalling and mass loss are decreased as penetrability increased.