钢纤维聚合物混凝土与旧混凝土界面粘结性能及数值分析

发布时间：2018-03-07 00:21

本文选题：钢纤维混凝土　切入点：界面粘结　出处：《重庆交通大学》2016年硕士论文　论文类型：学位论文

【摘要】：本文通过不同掺量的聚合物、硅灰加入到钢纤维混凝土中作为新浇筑混凝土,研究新旧混凝土的界面粘结性能和断裂性能,同时研究不同界面处理工艺对新旧混凝土界面粘结性能的影响,和不同脱粘面积对新旧混凝土粘结后断裂性能的影响,并且对断裂试验进行了有限元模拟。本次研究主要进行了以下试验分析:(1)混凝土抗压、抗折试验,研究不同掺量的聚合物、硅灰对钢纤维混凝土的影响;(2)混凝土钻芯拉拔试验,测得新旧混凝土界面粘结强度,研究不同掺量的聚合物、硅灰以及不同界面处理工艺对钢纤维混凝土与旧混凝土界面粘结强度的影响;(3)混凝土三点弯曲梁试验,研究不同掺量的聚合物、硅灰以及不同脱粘面积对新旧混凝土粘结断裂性能的影响;(4)运用有限元软件ABAQUS对三点弯曲梁试验进行数值模拟分析,比较不同脱粘面积的下新旧混凝土的断裂性能。通过上述试验,可以得到以下结论:(1)硅灰对混凝土的基本力学性能都有明显的提高作用,并且在本次试验所用掺量中9%为最佳,聚合物的加入,并不能明显提高混凝土的力学性能,但能增加其柔性;(2)聚合物掺入普通混凝土中时,能明显提高其界面粘结性能,但对于钢纤维混凝土而言,影响不明显;硅灰对普通混凝土和钢纤维混凝土,均能提高其界面粘结强度;同时在涂抹界面剂时其粘结强度最大,切槽次之,未做处理最小。(3)聚合物对混凝土断裂过程中的峰值荷载和断裂韧度并没有明显的提高作用,硅灰能够有效的提高断裂过程中的峰值荷载和断裂韧度;不同的脱粘面积时,脱粘面积越大,试件的峰值荷载越小,对应的位移越大,其断裂韧度不断减小;(4)有限元分析结果与试验结果显示出的趋势基本一致,但由于数值分析所用参数一部分来自试验,一部分来自理论计算,使得数值分析的结果与实际也存在一定的差异。
[Abstract]:In this paper, the interfacial bond and fracture properties of new and old concrete are studied by adding silica fume into steel fiber reinforced concrete with different amount of polymer. At the same time, the effects of different interfacial treatment processes on the bond properties of new and old concrete and the effect of different debonding areas on the fracture properties of new and old concrete are studied. And the fracture test was simulated by finite element method. In this study, the following tests were carried out to analyze the compressive and flexural strength of concrete, and to study the influence of different amount of polymer and silica fume on steel fiber reinforced concrete (SFRC) core drawing test. The interfacial bond strength of new and old concrete was measured. The effect of different amount of polymer, silica fume and interfacial treatment technology on bond strength between steel fiber concrete and old concrete was studied. The effects of different amount of polymer, silica fume and different debonding area on bond fracture properties of new and old concrete are studied. Numerical simulation analysis of three-point bending beam test is carried out by using finite element software ABAQUS. By comparing the fracture properties of new and old concrete with different debonding areas, the following conclusions can be drawn from the above tests: (1) silica fume can obviously improve the basic mechanical properties of concrete, and 9% is the best one in this experiment. The addition of polymer can not obviously improve the mechanical properties of concrete, but it can increase the flexibility of concrete. When the polymer is added into ordinary concrete, it can obviously improve the interfacial bond property, but for steel fiber reinforced concrete, the influence is not obvious. Silica fume can improve the interfacial bond strength of both ordinary concrete and steel fiber concrete. Without treatment, the maximum load and fracture toughness of concrete during fracture were not significantly increased by the polymer, but the peak load and fracture toughness were increased effectively by silica fume, and different debonding areas were obtained. The larger the debonding area is, the smaller the peak load is and the larger the displacement is. The fracture toughness of the specimen decreases continuously. (4) the results of finite element analysis are basically consistent with the experimental results. However, some of the parameters used in the numerical analysis come from the test. Some of them come from theoretical calculation, which makes the results of numerical analysis different from the actual ones.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU528

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