【作者】 左龙华；

【导师】 傅衣铭； 刘腾喜；

【作者基本信息】 湖南大学 ， 工程力学， 2006， 硕士

【摘要】 本论文以钢筋混凝土构件为研究对象,基于锈胀力研究理论和弹性力学,采用钢筋混凝土结构基本原理,系统地研究了钢筋锈蚀后钢筋混凝土结构的耐久性问题,例如钢筋的力学性能,锈蚀钢筋与混凝土之间的粘结强度,剪切强度,抗弯强度等。本论文的研究成果可为混凝土结构耐久性的设计计算提供理论依据,具有重要的工程应用意义。本论文的主要研究内容如下。对锈蚀变形钢筋与混凝土之间的粘结力进行了研究。从变形钢筋的表面几何特征出发,考虑了钢筋锈蚀后钢筋与混凝土接触面的特征,例如钢筋横肋在锈蚀状态下的细观力学模型,钢筋锈蚀后钢筋横肋高度的变化和锈蚀产物的生成对粘结力的影响。通过分析接触面上各种力的分布形式及相互关系,建立了有横向钢筋和无横向钢筋约束作用下,钢筋与混凝土之间粘结力的计算表达式,且与相关文献的结果进行了比较。对锈蚀钢筋混凝土梁的斜截面抗剪承载力进行了研究。对于锈蚀无腹筋梁,从开裂面的受力状态出发,根据开裂面的抗剪机制,分析了锈蚀无腹筋梁的抗剪强度。对于锈蚀有腹筋梁的抗剪承载力问题,基于未锈蚀有腹筋梁抗剪强度公式建立的原理,即未锈蚀有腹筋梁的抗剪强度为相应未锈蚀无腹筋梁的抗剪强度和箍筋对梁抗剪强度贡献两部分的叠加,考虑箍筋的约束作用对斜截面抗剪强度的贡献,建立了有腹筋构件斜截面抗剪承载力的计算表达式,且与相关文献的结果进行了比较。对锈蚀钢筋混凝土构件的正截面抗弯承载力进行了研究。根据锈蚀钢筋与混凝土之间的粘结强度,对锈蚀钢筋混凝土梁进行分类,并且根据未锈蚀钢筋混凝土梁和锈蚀钢筋混凝土梁极限粘结强度和平均极限粘结强度的相对大小,分别对锈蚀钢筋混凝土梁在不同相对粘结强度下的抗弯强度进行了分析。同时,当锈蚀梁主筋完全锈蚀后,分别对锚固端未锈蚀和锈蚀但还可以提供足够锚固能力的两种情况,进行了抗弯强度的理论分析,建立了抗弯承载力的计算表达式,且与相关文献的结果进行了比较。更多还原

【Abstract】 In this thesis, based on the theories of corrosion expansion force and the elasticity, by adopting the theory of reinforced concrete structures, the durability problems of reinforcing concrete structures considering the corrosion of reinforcing bar are studied systematically, such as the change of steel mechanical properties, the bond strength between corroded reinforcement and concrete, the shear carrying capacity and the flexural carrying capacity of the corroded reinforced concrete (RC) structural elements. The present research results are significant not only in the theoretical calculation and designs but also in the practical engineering for the durability of concrete structures. The main researching content is as follows.The bond strength between corroded deformed bars and concrete is studied. According to the geometrical characteristics of the surface on the deformed bars, considering the interfacial properties of the corrosion reinforcement and concrete, such as the microscopic mechanics model of corroded reinforcement ribs, the deterioration of ribs on the bearing surface of the deformed bars after corrosion and the effect of corrosion products of corrosion reinforced bar on the bond strength, and analyzing the distribution and interaction of the forces on the surface of the corrosion reinforcement and concrete, the calculation expressions of the bond strength between corroded deformed bars and concrete with and without transverse steel are established. The comparative studies are carried out to verify the validity of the present method.The shear carrying capacity of the corroded RC structural elements is investigated. Based on shear transfer mechanism and carrying capacity of the cracking surface of RC members, the shear strength expression of the corroded RC structural elements without web reinforcement is obtained originally. The shear strength of the no corroded RC beams with stirrups is divided by two parts, that is the strength provided by the stirrups and the beams without web reinforcement. On the basis of this shearing mechanism of RC structural elements with web reinforcement, considering the confining effects of the stirrups, the shear carrying capacity expression of the corroded RC structural elements is given. The present results are compared with corresponding references and some reasonable conclusions are drawn.The flexural carrying capacity of the corroded RC structural elements is investigated. The corroded reinforced concrete beams are classified according to the bond strength between the corroded reinforcement and concrete. Considering the relative size of limit and average bond strengths of the reinforced concrete beams更多还原