A three-point bending test apparatus for testing concrete-like materials at high temperatures has been developed. Notched specimens were heated at a rate of 3.3°C per minute to various temperatures, up to a maximum of 900°C. They were then subjected to…
A three-point bending test apparatus for testing concrete-like materials at high temperatures has been developed. Notched specimens were heated at a rate of 3.3°C per minute to various temperatures, up to a maximum of 900°C. They were then subjected to a three-point bending test while the temperature was held constant. The maximum peak load occurred in the temperature range of 300 to 500°C, and decreased sharply at higher temperatures. The experimental results demonstrated a noticeable nonlinear effect of the temperature on the fracture resistance of mortar for high performance concrete. Tenacity parameters such as the stress intensity factor or the fracture energy were found to evolve with testing temperature. Temperatures in the range of 300 to 500°C led to optimal values for these parameters, whereas at higher temperatures, the parameter values decreased considerably. SEM micrographs of the heated specimens after mechanical tests facilitated the understanding of the macroscopic behaviour.