氯盐环境下钢筋与纳米粘土混凝土粘结性能研究

发布时间：2018-05-04 11:09

本文选题：纳米粘土 + 粘结性能　；参考：《大连海事大学》2015年硕士论文

【摘要】：氯盐环境中富含氯离子,氯离子渗入混凝土内部,造成钢筋锈蚀,导致钢筋与混凝土间的粘结性能退化,致使钢筋混凝土结构损伤、破坏,影响其承载力及耐久性,甚至引发工程事故。如何防止氯盐环境下混凝土中钢筋锈蚀,提高钢筋混凝土结构耐久性及使用寿命,已成为当今世界关注的焦点问题。纳米粘土材料能够改变水泥基材料的物理力学性能,为研制新型高耐久性混凝土材料开辟了新思路。纵观国内外有关氯盐环境下钢筋与混凝土粘结性能的研究现状,在国家自然科学基金(项目编号：51178069)和教育部新世纪优秀人才基金(项目编号：NCET-11-0860)的资助下,本文对纳米粘土混凝土与锈蚀钢筋间的粘结性能开展了试验研究。主要研究内容如下：(1) 纳米粘土混凝土氯离子渗透性能研究。利用恒电压下电化学加速腐蚀试验,在实验室内完成了四种纳米粘土掺量下60个试件的渗透试验。研究了不同掺量纳米粘土对混凝土渗透深度及混凝土内部氯离子浓度的影响规律。(2)纳米粘土混凝土内部钢筋锈蚀长期监测研究。采用实验室自然浸泡法,对不同掺量下纳米粘土钢筋混凝土试件进行长期浸泡,监测试件内钢筋锈蚀的变化情况。(3) 钢筋与纳米粘土混凝土粘结性能研究。完成了96个标准圆柱体试件的拉拔试验,探讨了纳米粘土掺量及腐蚀时间对钢筋与纳米粘土混凝土粘结性能及混凝土内部钢筋锈蚀情况的影响,得到了不同掺量下钢筋与纳米粘土混凝土的粘结-滑移曲线、极限粘结强度。(4) 纳米粘土混凝土与钢筋粘结性能的数值模拟分析。对拉拔试验结果进行数值模拟,探讨了不同掺量纳米粘土对钢筋混凝土构件粘结性能的影响,给出了有限元分析时需考虑钢筋与混凝土之间粘结滑移的建议。
[Abstract]:Chloride salt environment is rich in chloride ions. Chloride ions infiltrate into the concrete, causing corrosion of steel bar, degradation of bond property between reinforcement and concrete, damage and damage of reinforced concrete structure, affecting its bearing capacity and durability. Even caused engineering accidents. How to prevent the corrosion of steel bars in concrete under chloride environment and improve the durability and service life of reinforced concrete structures have become the focus of attention in the world. Nano-clay materials can change the physical and mechanical properties of cement-based materials and open a new way for the development of new high durability concrete materials. The present situation of research on bond properties of reinforcement and concrete in chloride environment at home and abroad is reviewed. Supported by the National Natural Science Foundation (project No.: 51178069) and the Ministry of Education New Century Talent Fund (Project No.: NCET-11-0860), In this paper, the bond behavior between nano clay concrete and corroded steel bar is studied experimentally. The main research contents are as follows: 1) the chloride ion permeability of nano-clay concrete. By means of electrochemical accelerated corrosion test at constant voltage, the permeation tests of 60 specimens with four kinds of nano-clay were carried out in the laboratory. The effect of different amount of nano-clay on the penetration depth of concrete and the concentration of chloride ions in concrete is studied. The long-term monitoring of steel bar corrosion in nanocrystalline clay concrete is studied. By using the natural immersion method in laboratory, the specimens of nano-clay reinforced concrete with different contents were soaking for a long time, and the change of corrosion of steel bars in the specimens was monitored. 3) the bond property between steel bar and nano-clay concrete was studied. The drawing tests of 96 standard cylindrical specimens were completed, and the effects of nano-clay content and corrosion time on the bond properties of steel bar and nano-clay concrete and the corrosion of steel bar inside concrete were discussed. The bond-slip curve and ultimate bond strength of reinforced and nano-clay concrete with different contents are obtained. The numerical simulation of bond behavior between nano-clay concrete and steel bar is obtained. In this paper, the numerical simulation of the results of drawing test is carried out, and the influence of different amount of nano-clay on the bond behavior of reinforced concrete members is discussed, and the suggestion that the bond-slip between steel bar and concrete should be considered in finite element analysis is given.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528

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