钢筋混凝土粘结滑移本构试验研究及有限元分析

发布时间：2018-10-22 13:02

【摘要】：粘结是钢筋和混凝土之间一种复杂的相互作用,通过粘结传递两者之间的应力、协调变形,足够的粘结是钢筋混凝土构件发挥良好工作性能的基础。因此,研究钢筋与混凝土之间锚固粘结,对于评估混凝土结构使用性能意义重大。本文通过梁端式拔出试验研究箍筋间距与保护层厚度对粘结滑移性能的影响,并利用精细的有限元模型进行对比验证,将得到的粘结滑移本构模型应用于混凝土简支梁力学性能分析。本文的主要研究内容如下： (1)通过梁端式拔出试验研究了保护层厚度及箍筋间距对极限粘结强度的影响,并建立反映不同约束状况的经验公式。基于其他学者研究成果及本文试验数据,建立了考虑不同保护层厚度及箍筋间距的粘结滑移本构关系。 (2)基于本文梁端式拔出试验,通过有限元软件建立精细的三维实体梁端式模型,模拟带肋钢筋从混凝土中拔出劈裂破坏的全过程。从有限元的角度分析保护层厚度及箍筋间距对粘结滑移本构关系的影响,并与本文试验结果进行对比验证。本文还得到了拔出钢筋及混凝土在拔出过程中的各处应力分布,弥补了部分试验难以测得的试验数据。 (3)基于本文梁端式拔出试验建立的粘结滑移本构模型,采用有限元程序对不同锈蚀率的混凝土简支梁梁进行有限元分析并与试验对比,同时还考察了有无考虑位置函数情况下试验梁的力学性能。在此基础上,分析了不同锈蚀下锚固长度、保护层厚度、受拉纵筋直径、受拉纵筋数量等不同参数下混凝土梁的极限承载与极限挠度变化规律。
[Abstract]:Bond is a kind of complex interaction between steel bar and concrete. It is the foundation of good working performance of reinforced concrete members to transfer stress and coordinate deformation by bond. Therefore, the study of Anchorage bond between reinforcement and concrete is of great significance to evaluate the performance of concrete structures. In this paper, the effects of stirrups spacing and cover thickness on bond-slip properties are studied by beam end pull-out test, and the fine finite element model is used to compare and verify the effect of stirrups spacing and protective layer thickness on the bond-slip behavior. The bond-slip constitutive model is used to analyze the mechanical properties of simply supported concrete beams. The main contents of this paper are as follows: (1) through beam end pull-out test, the influence of protective layer thickness and stirrups spacing on ultimate bond strength is studied, and empirical formulas reflecting different constraint conditions are established. Based on the research results of other scholars and the experimental data in this paper, a bond-slip constitutive relation considering the thickness of different protective layers and the spacing of stirrups is established. (2) based on the beam end pull-out test in this paper, A fine 3D solid beam end model was established by finite element software to simulate the whole process of pulling ribbed steel bar out of concrete. The influence of the thickness of protective layer and the spacing of stirrups on the bond-slip constitutive relationship is analyzed from the point of view of finite element method and the results are compared with the experimental results in this paper. In this paper, the stress distribution in the pull-out process of steel bar and concrete is also obtained, which makes up for some test data which are difficult to measure. (3) the bond-slip constitutive model based on the beam end pull-out test in this paper. The finite element analysis of simply supported concrete beams with different corrosion rates was carried out by finite element program and compared with the test results. At the same time, the mechanical properties of the test beams with or without the position function were investigated. On this basis, the variation law of ultimate bearing capacity and ultimate deflection of concrete beams under different corrosion conditions, such as anchoring length, thickness of protective layer, diameter of tensile longitudinal tendons and number of tensile longitudinal tendons, are analyzed.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU375

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