| 摘要: |
| 研究了冻融循环氯盐侵蚀和弯拉荷载冻融循环氯盐侵蚀作用下混凝土的劣化行为，分析了氯盐侵蚀和冻融损伤的相互影响，以及弯拉荷载对混凝土抗冻性能的影响.结果表明：冻融循环导致混凝土微裂纹萌生、扩展，使孔隙结构遭到破坏，从而加速了氯盐的侵入；氯盐的侵入会影响混凝土的饱水度和孔隙溶液的迁移，加速冻融循环造成的表面剥落和内部损伤.在弯拉荷载冻融循环氯盐侵蚀作用下，混凝土的破坏形式以表面剥落为主，弯拉荷载会加速劣化，甚至使其脆性断裂. |
| 关键词: 弯拉荷载 冻融循环 氯离子侵入 混凝土 |
| DOI：103969/j.issn1007 9629201605006 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(51320105016) |
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| Deterioration of Concrete Caused by Freeze Thaw Cycles Combined with Chloride Attack under Flexural Load |
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CAO Yin, WANG Ling, WANG Zhendi, YAO Yan
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State Key Laboratory of Green Building Materials, China Building Materials Academy, Beijing 100024, China
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| Abstract: |
| Deterioration of concrete caused by freeze thaw cycles combined with chloride attack under flexural load was tested and analyzed. It is shown that for concrete under combined freeze thaw cycles and chloride attack, the generation and propagation of micro cracks caused by frost action degrades the pore structure of concrete, which accordingly accelerates chloride attack. On the other hand, the effect of chloride on the migration of pore solution and the saturation of concrete accelerates surface scaling and inner damage of concrete during freeze thaw action. Under combined flexural load, freeze thaw cycles and chloride attack, surface scaling is still the most serious problem, and the long term loading accelerates the deterioration of concrete and even increases the probability of rupture failure. |
| Key words: flexural load freeze thaw cycle chloride attack concrete |
