高温后珊瑚海水海砂混凝土力学性能试验研究  

Experimental Study on Mechanical Properties of Coral Seawater Sea Sand Concrete after High Temperature

作　　者：胡强[1,2] 李佳成 陈宇良 陈宗平[1,3] HU Qiang;LI Jiacheng;CHEN Yuiang;CHEN Zongping(School of Civil Engineering,Guangxi University of Science and Technology,Liuzhou 545006,China;Guangxi University Key Laboratory of Disaster Prevention and Mitigation and Prestress Technology,Liuzhou 545006,China;Key Laboratory of Disaster Prevention and Structure Safety of the Ministry of Education,Guangxi University,Nanning 530004,China)

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006 [2]广西高校防灾减灾与预应力技术重点实验室,广西柳州545006 [3]广西大学工程防灾与结构安全教育部重点实验室,广西南宁530004

出　　处：《防灾减灾工程学报》2024年第3期544-550,567,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：中国博士后科学基金(2021M693854);广西自然科学基金面上项目(2020GXNSFAA159150);广西科技大学研究生教育创新计划项目(GKYC202229)资助。

摘　　要：为研究高温后珊瑚海水海砂混凝土(CSSC)的力学性能,设计制作了30个CSSC试件,进行常温与高温后轴心受压和静力受压弹性模量试验。通过试验观察了试件高温后的表观变化和轴心受压破坏形态,获取了轴心受压全过程应力—应变曲线、弹性模量及烧失率等参数,深入高温后CSSC微观结构变化机制,得到了受火温度对CSSC力学性能的影响规律,揭示了高温作用后CSSC的力学性能退化机理。结果表明:随着受火温度的增加,CSSC力学性能不断劣化。T=200℃时CSSC轴心抗压强度和弹性模量分别比常温时下降了26.52%,6.19%,混凝土具有较好的力学性能;T=400℃时CSSC弹性模量下降迅速,弹性模量损失率为65.48%,但与T=200℃相比混凝土轴心抗压强度上升了6.4%;T=600℃时CSSC轴心抗压强度下降迅速,强度损失率为66.74%;T=800℃时CSSC破坏严重,已无法测得有效的弹性模量。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.

关 键 词：珊瑚海水海砂混凝土 高温 微观结构 受压性能 强度退化机理 

分 类 号：TU443[建筑科学—岩土工程]