【作者】 谢晓鹏；

【导师】 高丹盈； 赵军；

【作者基本信息】 郑州大学 ， 结构工程， 2004， 硕士

【摘要】 我国混凝土结构量大面广,解决混凝土结构的耐久性问题已十分紧迫。所谓混凝土结构的耐久性,是指混凝土结构在自然环境、使用环境及材料内部因素的作用下,在设计要求的目标使用期内,不需要花费大量资金加固处理而保持其安全、使用功能和外观要求的能力。混凝土的抗冻融性能和碳化性能是耐久性的重要研究内容。本文对钢纤维混凝土抗冻融性能及其抗碳化性能进行了试验研究。冻融试验以混凝土强度等级和钢纤维体积率为变化参数,共制作了90个尺寸为100mm×100mm×100mm和45个100mm×100mm×400mm的混凝土试件。经冻融循环50次和75次后,测试试件的基本力学性能。以试验数据为依据,分析了冻融循环次数、混凝土强度等级、钢纤维体积率等因素对钢纤维混凝土冻融后基本力学性能(抗压强度、劈拉强度、抗折强度)及其质量损失的影响规律。研究结果表明,钢纤维提高了混凝土的抗冻性能。碳化试验以混凝土的强度等级、钢纤维体积率、碳化龄期为变化参数,通过对366个100×100×100mm、183个100×100×400mm的混凝土试件进行碳化前后对比试验,分别测试了钢纤维混凝土碳化前后的基本力学性能(抗压强度、劈拉强度、抗折强度)和各个龄期混凝土的碳化深度,观察了钢纤维混凝土受力破坏全过程及其破坏形态,探讨了钢纤维对混凝土的增强机理,分析了钢纤维体积率、混凝土强度等级、碳化龄期等因素对混凝土基本力学性能和碳化深度的影响,提出了钢纤维混凝土抗压强度-碳化深度以及钢纤维混凝土碳化龄期-碳化深度的计算公式。更多还原

【Abstract】 Concrete structures are widely used in China. The consideration about durability of concrete structures has become very urgent at present. What we call the durability of concrete structure is that concrete structures have the ability of keeping their security, function and appearance requirement without costing much money to reinforce them under the influence of natural environment, application environment and internal factors of material. The experimental studies of the resisting freeze-thaw and carbonization capability of the steel fiber reinforced concrete have been done in this dissertation.In the freeze-thaw experiment , the grade of concrete intensity and the volume fraction of steel fiber are regarded as variable parameters and that 90 concrete specimens with the size of 100mmXI00mmXI00mm and 45 concrete specimens with the size is 100 mmX 100mm X400mm have been made. After the freeze-thaw circulations (50, 75 times), the basic mechanical property of the specimens has been tested. Based on the test data, it has been analyzed that the influence of the freeze-thaw circulation time, the grade of concrete intensity and the volume fraction of steel fiber on the basic mechanic property , such as compressive strength, splitting strength and flexural strength of steel fiber reinforced concrete, and on mass loss of this kind of material. The study result shows that steel fiber improved the frost-resisting property of concrete.In the carbonization experiment, the grade of concrete intensity, the volume fraction of steel fiber and carbonization time are taken as variable parameters. Through the carbonization experiment of 366 concrete specimens with the size of lOOmmX lOOmmX 100mm and 183 concrete specimens with the size of 100 mmX100mm X400mm, the basic mechanic properties before carbonization and after carbonization, such as compressive strength, splitting strength and flexural strength of concrete, of steel fiber reinforced concrete are measured, and also carbonization depth at every defined carbonization time. At the same time, the whole failure process and the failure mode of steel fiber reinforced concrete are surveyed. The reinforced mechanism of the steel fiber is studied, and theeffects of the volume fraction of steel fiber, the grade of concrete intensity, carbonization time on the basic mechanic property and carbonization depth are analyzed. At last, two experiment empirical formulas about carbonization depth have been put forward:更多还原