论文标题:路用混凝土疲劳性能研究
Fatigue Performance of Concrete Pavement
论文作者
论文导师 易志坚,论文学位 硕士,论文专业 工程力学
论文单位 重庆交通大学,点击次数 66,论文页数 91页File Size4913K
2007-04-01论文网 http://www.lw23.com/lunwen_436941587/
Cement Concrete Pavement;; Fracture Mechanics;; Flexible Fiber Reinforced Concrete;;Fatigue
本文分析了传统水泥混凝土路面的破坏过程,基于断裂力学原理揭示的“过渡层”对混凝土疲劳性能的影响机理,通过对含有过渡层的水泥混凝土试样和通过设置隔离层消除过渡层后的水泥混凝土试样的疲劳对比实验,得出了两者疲劳性能的差异,建立了混凝土的疲劳方程,验证了“过渡层”的存在对混凝土疲劳性能的严重影响和对混凝土路面的影响。 基于纤维混凝土裂尖闭合力阻裂模型,揭示了柔性纤维在混凝土中的“阻裂墙”效应,通过柔性纤维混凝土的疲劳实验,建立了柔性纤维混凝土的疲劳方程。疲劳试验验证了柔性纤维在混凝土中的“阻裂墙”效应,显著改善了混凝土的疲劳性能,是理想的克服水泥混凝土路面疲劳破坏的优良材料。 本文分析表明;设置隔离层的路面结构能消除过渡层对混凝土面层疲劳性能的显著影响,是一种理想的路面结构形式;在混凝土中掺加柔性纤维,能改善混凝土的疲劳性能,达到延长路面实际使用寿命的目的。
In this paper, the author has analyzed the failure process of the traditional cement concrete pavement. On the basis of fracture mechanics, the author has revealed the principle of intermediate layer"s influence on concrete fatigue performance. By comparison fatigue test results, the author has found the differences between fatigue performance of cement concrete samples with an intermediate layer and that with an insulating layer. The author has proved the intermediate layer is deleterious to the fatigue performance of concrete and concrete pavement, and concluded that the insulating layer can prevent the intermediate layer from generating. The author has constituted the fatigue equation of concrete also. Based on the closing force crack-resistant model in crack tips, the author has revealed the flexible fibers" crack-resistant-wall effect in flexible fiber reinforced concrete, which has been verified by fatigue tests. The author has built the fatigue equation of flexible fiber reinforced concrete, concluded flexible fibers can remarkably improve the concrete"s fatigue performance, and proved that flexible fiber reinforced concrete is a kind of excellent material for cement concrete pavement. In general, the author has made the following conclusions: Firstly, concrete pavement structure with an insulating layer is an ideal pavement structure type, which can enormously diminish the intermediate layer"s influence on the fatigue performance of the concrete surface course. Secondly, flexible fibers in concrete can remarkably improved the fatigue performance of concrete, and by using flexible fibers, concrete pavement"s actual service life can be prolonged.
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