| 摘要: |
| 为探究高温对页岩陶粒轻骨料混凝土（SCLAC）蠕变特性的影响，进行了室温至800 ℃后SCLAC单轴压缩试验、分级压缩蠕变试验和扫描电镜（SEM）试验，分析了SCLAC质量损失、抗压强度损失、蠕变特性及微观结构特征.结果表明：随温度升高，SCLAC的内部微观结构变得疏松，质量、抗压强度逐渐降低，800 ℃后质量损失率为9.54%，抗压强度损失率为63.88%；随温度升高和应力水平增加，蠕变应变和蠕变速率增大，蠕变历时和蠕变破坏临界应力水平减小；温度高于600 ℃时蠕变应变明显增大，在相同应力水平下，与室温相比600 ℃后的蠕变应变增加了82.76%.基于试验结果对Burgers蠕变模型参数进行辨识，所得理论曲线与减速蠕变阶段和等速蠕变阶段的试验数据吻合较好. |
| 关键词: 轻骨料混凝土 高温 蠕变 微观结构 |
| DOI：10.3969/j.issn.1007-9629.2021.05.027 |
| 分类号:TU528.2 |
| 基金项目:中国博士后科学基金面上资助项目（2020M681974）；安徽省高等学校自然科学研究项目（KJ2020A0297）；安徽理工大学校级资助项目（QN2019115）；安徽理工大学研究生创新基金（2020CX1004） |
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| Creep Behavior of Shale Ceramsite Lightweight Aggregate Concrete Exposed to High Temperature |
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LIU Yushan1, PANG Jianyong1, YAO Weijing1,2
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1.School of Civil Engineering and Architecture， Anhui University of Science and Technology， Huainan 232001， China;2.Postdoctoral Station of Civil Engineering， Anhui University of Science and Technology， Huainan 232001， China
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| Abstract: |
| To study the influence of high temperature on the creep behavior of shale ceramsite lightweight aggregate concrete（SCLAC）， uniaxial compression test， multistage creep test and scanning electron microscope（SEM） test of SCLAC exposed from room temperature to 800 ℃ were carried out. The loss of mass and compressive strength， creep behavior and microstructure characteristics of SCLAC were analyzed. The results show a decrease in the mass and compressive strength and the internal microstructure becomes more loose， as the temperature rises. After 800 ℃， the loss ratio of mass and compressive strength is 9.54% and 63.88%， respectively. With higher target temperature and higher stress level， the creep strain and creep rate increase， while the creep failure threshold stress and creep duration reduce， significantly. Furthermore， the creep strain of SCLAC exhibits a considerable increase above 600 ℃ and the creep strain under the same loading ratio at 600 ℃ increases by 82.76%， compared to the creep at room temperature. Based on the test results， the Burgers creep model agrees well with the creep test data at the primary creep stage and stable creep stage. |
| Key words: lightweight aggregate concrete high temperature creep microstructure |
