高温后珊瑚海水海砂混凝土力学性能试验研究OA北大核心CSTPCD

To study the mechanical properties of Coral Seawater Sea Sand Concrete(CSSC)after ex-posure to high temperatures,axial compression and static compression elastic modulus tests were con-ducted on 30 CSSC specimens at room and high temperatures.The axial compression failure patterns and apparent changes of the specimens after exposure to high temperatures were observed,and param-eters such as the complete stress-strain behavior under axial compression,elastic modulus,and weight loss rate were obtained.In conjunction with an in-depth analysis of the mechanisms of micro-structural changes in CSSC after exposure to high temperatures,the study explored the influence of fire temperature on CSSC's mechanical properties and revealed the degradation mechanism of these properties after high-temperature exposure.The results demonstrated a progressive decline in the me-chanical properties of CSSC as the fire temperature increased.At 200 ℃,compared to specimens at room temperature,the axial compressive strength and elastic modulus of CSSC decreased by 26.52％and 6.19％,respectively,indicating good mechanical properties.At 400 ℃,the elastic modulus of CSSC decreased rapidly,with a loss of 65.48％,but its axial compressive strength increased by 6.4％compared to specimens at 200 ℃.At 600 ℃,the axial compressive strength of CSSC exhibited a rapid decline,with a strength loss rate of 66.74％.The CSSC was severely damaged at 800 ℃,making it impossible to measure its effective elastic modulus.