| 摘要: |
| 为评估风积沙混凝土碳化-盐冻作用后的耐久性能，以质量损失率、相对动弹性模量、抗压强度为指标，分析碳化作用对风积沙混凝土抗冻性能的影响，通过扫描电镜（SEM）与核磁共振（NMR）技术分析碳化-盐冻后其内部结构和孔结构变化特征，采用Wiener随机过程概率分布预测碳化作用后风积沙混凝土盐冻循环寿命. 结果表明：碳化作用提高了混凝土强度，且使得盐冻循环作用下质量损失率增加，相对动弹性模量下降；无害孔与有害孔的比值反应了混凝土内部结构损伤特征；相对动弹性模量对混凝土盐冻环境最敏感，碳化28 d混凝土经受372次盐冻循环后完全失效. |
| 关键词: 风积沙混凝土 碳化作用 Wiener随机过程 寿命预测 |
| DOI：10.3969/j.issn.1007-9629.2023.06.007 |
| 分类号:TU528.01 |
| 基金项目:国家自然科学基金资助项目（52268044）；内蒙古自治区自然科学基金资助项目（2021LHMS05019）；内蒙古科技大学建筑科学研究所开放基金项目（JYSJJ-2021Q01） |
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| Damage Deterioration Mechanism and Life Prediction of Aeolian Sand Concrete under Carbonization and Salt Freezing |
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DONG Wei1,2, WANG Xuesong1, JI Yajing1, WANG Dong1, XUE Gang1
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1.College of Civil Engineering， Inner Mongolia University of Science and Technology， Baotou 014010， China;2.Inner Mongolia Autonomous Region Engineering Technology Research Center of Building Structure Disaster Prevention and Reduction， Inner Mongolia University of Science and Technology， Baotou 014010， China
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| Abstract: |
| In order to evaluate the durability of aeolian sand concrete after carbonation and salt freezing，the mass loss rate，relative dynamic elastic modulus and compressive strength were used as indicators to analyze the effect of carbonation on the frost resistance of aeolian sand concrete. The internal structure and pore structure change characteristics after carbonation-salt freezing were analyzed by scanning electron microscope（SEM） and nuclear magnetic resonance（NMR） techniques，and the freeze-thaw cycle life of aeolian sand concrete after carbonation was predicted by Wiener stochastic process probability distribution. The results show that carbonation could improve the strength of concrete under the situation of the freeze-thaw cycles， and the mass loss rate is increased after the carbonation. At the same time the relative dynamic modulus of elasticity is reduced. The ratio of harmless hole to harmful hole reflects the damage characteristics of concrete internal structure. The relative dynamic elastic modulus of concrete is the most sensitive index to freeze-thaw environment，and after 28 days of carbonation， the concrete is completely invalidated after 372 cycles of salt freezing. |
| Key words: aeolian sand concrete carbonization Wiener stochastic process life prediction |
