【作者】 王辉；

【导师】 刘来君；

【作者基本信息】 长安大学 ， 建筑与土木工程， 2011， 硕士

【摘要】 FRP(Fiber Reinforced Polymer)是一种新型的修复补强材料,具有轻质、高强、耐疲劳、耐腐蚀及耐久性好、施工简便以及不增加构件截面尺寸等优点,因此被广泛地应用于结构的修复与加固实践,尤其在加固柱、桥墩方面。FRP加固混凝土柱除了可以提高混凝土柱的强度之外,还可以大幅度提高其变形能力。国内外学者关于FRP约束混凝土柱进行了大量的试验研究和理论分析,并取得了一些成果,但理论研究远滞后于实际工程的应用。目前的研究成果大部分是在模型试验的基础上提出的,而模型试验都研究是小直径柱的加固,完全不能真实的反应工程实际中大直径墩柱的加固情况,现有的理论研究也都没有涉及到直径对墩柱加固效果的影响,本文由此开展研究,分析直径对约束混凝土加固效果的影响。由于混凝土结构本身特点比较复杂,必须对试验的全过程进行数值分析。本文利用有限元软件ANSYS/LS-DYNA,选取较为合适的单元来模拟混凝土单元和碳纤维布单元,模拟碳纤维布CFRP (Carbon Fiber Reinforced Polymer laminate)加固混凝土柱的轴心受压试验得出与试验吻合较好的结果,在此基础上进行数值仿真试验。在保证长细比相同的情况下,模拟不同直径对约束混凝土柱加固效果的影响,得到了不同直径的混凝土柱模型加固后的极限承载力、混凝土和碳纤维布此时的应力应变分布情况、混凝土裂缝的开展过程、碳纤维布被拉断的开展过程以及混凝土破碎构件整体破坏的全过程等直观的信息。通过对大直径与小直径混凝土柱模型的比较,得出其破坏形式的不同,对于大直径CFRP的加固效果并不太理想。建议在以后的工程实际中对于用CFRP加固混凝土墩柱的情况需要考虑柱体的直径对其加固效果的影响。ANSYS/LS-DYNA有限元动力分析有限元方法可以在一定程度上有效的代替试验分析法,节约人力、物力、财力和时间,其分析结果可以较为准确的动态显示约束混凝土柱破坏整个过程,为碳纤维布的实际加固工程提供理论参考。更多还原

【Abstract】 FRP is a new type of repair and reinforcement material, with lightweight, high strength, fatigue resistance, corrosion resistance and durability, and construction is simple and does not increase the member section sizes, etc., which is widely used in structural repair and reinforcement practice, especially in the reinforcement column, pier side. FRP reinforced concrete columns in addition to the strength of concrete columns can be improved, but also can greatly improve the deformation capacity. Domestic and foreign scholars on FRP confined concrete column do a lot of experimental and theoretical analysis, and achieved some results, but the theory is far behind the actual engineering application. Most of the current research on an experimental basis in the model proposed, while the model test study is the small diameter columns reinforcement, the response can not real practical engineering situation of large diameter reinforcing piers, the existing theoretical research not related to the diameter of the column reinforcement effect, the article from this research, analysis of the influence of confined concrete in diameter.Characteristics of the concrete structure itself is complex, test the whole process must be carried out numerical analysis. In this paper, finite element software ANSYS/LS-DYNA, select the more appropriate unit to simulate the concrete elements and carbon fiber unit. Simulated carbon fiber reinforced polymer laminate concrete columns under axial compressive load obtained in good agreement with the experimental results, in this based on the numerical simulation experiments. Guarantee the same in the case of slenderness ratio, the simulation of different diameter reinforced concrete columns on the binding effect, are a different diameter reinforced concrete column models the ultimate bearing capacity, concrete and carbon fiber at this time of stress and strain distribution of concrete Crack to carry out the process, carbon fiber sheet is pulled off the launching process and the crushing of concrete structures such as the overall destruction of the whole process visual information.Through the large diameter and small diameter concrete columns model comparison, the different forms of its destruction, for the large-diameter CFRP reinforcement effect and is not ideal. Recommended engineering practice in the future use of CFRP reinforced concrete piers for the case to consider the diameter of the cylinder to its strengthening effect. ANSYS/LS-DYNA finite element analysis method can be an effective substitute to some extent, test analysis, saving manpower, material, financial resources and time,the analysis results can be more accurate dynamic display of confined concrete columns undermine the whole process, as the actual carbon fiber reinforcement to provide a theoretical reference.更多还原