Experimental study on dynamic compressive properties of heated silicon carbide modified concrete

To investigate the high-temperature dynamic mechanical properties of silicon carbide-modified concrete, a combined experimental approach involving high-temperature heating and dynamic impact testing was employed. This study systematically analyzes the high-temperature dynamic strength characteristics, deformation behavior, energy absorption capacity, and dynamic crushing classification of silicon carbide-modified concrete. The experimental results demonstrate that the incorporation of silicon carbide significantly enhances the high-temperature mechanical performance of concrete. Specifically, the modification effect is more pronounced with larger and coarser silicon carbide particles. At an optimal incorporation rate of 14 % and a particle fineness of 400 mesh, the high-temperature dynamic performance of the modified concrete reaches its peak. For instance, at 600 ℃, the peak stress of the 14SCC400 (14 % SiC content, 400-mesh fineness) specimen is 37.47 % higher than that of plain concrete (PC) under the same conditions. Furthermore, as temperature increases, the peak strain and ultimate strain of the specimens initially rise and then subsequently decline. Additionally, coarser silicon carbide particles enhance the energy absorption capacity of concrete during failure, indicating improved impact toughness. The fragmentation pattern under high temperatures reveals that the proportion of large-sized fragments initially increases and then decreases with rising temperature. • Silicon carbide boosts concrete's high-temperature mechanical performance. • Coarser silicon carbide particles enhance the energy absorption capacity of concrete during failure. • The proportion of large-sized fragments initially increases and then decreases with rising temperature.