关于纤维混凝土加固板温度裂缝的分析

发布时间：2018-04-05 09:47

本文选题：碳纤维混凝土　切入点：钢纤维混凝土　出处：《天津大学》2014年硕士论文

【摘要】：在建筑工程中普遍存在着温度裂缝问题，温度裂缝给结构造成了很大的危害。本文研究了桥梁挡风板上碳纤维混凝土加固板的温度裂缝问题，桥梁挡风板靠近路面一侧用碳纤维混凝土加固板加固，置于自然环境下的桥梁挡风板，根据一天中日照方位的变化，桥梁挡风板在某一时间碳纤维混凝土加固板一侧处于阳面、另一侧处于阴面，或者碳纤维混凝土加固板一侧处于阴面、另一侧处于阳面，或者两侧同时受日光照射，根据这三种日照情况设置三种温度工况，利用FINAL有限元软件进行裂缝分析。由于挡风板两侧的温差和材料线膨胀的不同，使得挡风板两侧的形成变形差，本文研究由于温度变形的不协调而产生的裂缝。关于材料内部温度梯度分布的模型有双折线模式、幂函数模式、指数函数模式等。为了简化计算分析，本文不研究因为材料内部温度不均匀产生温度自应力对材料开裂的影响，将钢筋混凝土挡风板统一设置一个温升值，，将纤维混凝土加固板统一设置一个温升值。在模型建立中，纤维混凝土加固板与钢筋混凝土挡风板之间的连接简化为两种极限连接情况：（1）两者之间共用节点，并且相应的位置有螺栓连接。（2）两者之间采用非共用节点，只是用相应位置的螺栓连接。通过有限元分析结果得出：日照方位不同，纤维混凝土加固板的开裂情况不同；在相同条件下钢纤维混凝土加固板要比碳纤维混凝土加固板的温度裂缝少；纤维混凝土加固板的纤维分布情况和板厚均对加固板的开裂有一定的影响。
[Abstract]:The temperature crack is a common problem in the building engineering, and the temperature crack causes great harm to the structure.In this paper, the temperature crack of the CFRP reinforced slab on the bridge windshield is studied. The bridge windshield is strengthened with CFRP reinforced slab near the road surface, and the bridge windshield is placed in the natural environment.According to the change of sunshine azimuth during the day, the bridge windshield is on one side of the positive side, the other side on the shade, or the carbon fiber reinforced concrete plate on one side and the other side on the sunny side at a certain time.Or both sides are exposed to sunlight at the same time. According to the three kinds of sunlight, three kinds of temperature conditions are set up, and the crack analysis is carried out by using FINAL finite element software.Because of the difference of temperature difference and material linear expansion on both sides of the windshield, the deformation difference between the two sides of the windshield is different. The cracks caused by the incongruity of temperature deformation are studied in this paper.The models of temperature gradient distribution in materials include double broken line model, power function model, exponential function model and so on.In order to simplify the calculation and analysis, this paper does not study the effect of temperature self-stress on material cracking due to the uneven temperature inside the material, so the reinforced concrete windshield is uniformly set up as a temperature appreciation.The fiber reinforced concrete plate is uniformly set up for a temperature appreciation.In model building, the connection between fiber reinforced concrete reinforced slab and reinforced concrete windshield is simplified as two kinds of limit connection case: 1) the joint is shared between them, and the corresponding position is bolted connection.It is only connected by bolts in the corresponding position.The results of finite element analysis show that the crack of fiber reinforced concrete slab is different with different sunshine azimuth, and the temperature crack of steel fiber reinforced concrete plate is less than that of carbon fiber reinforced concrete plate under the same conditions.The fiber distribution and thickness of fiber reinforced concrete (FRC) plates have some influence on the cracking of the strengthened slabs.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U445.7

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