%0 Journal Article
%T 弯剪加固锈蚀梁抗弯性能试验<br>Experiment on flexural behavior of corroded beam with flexural and shear strengthening
%A 肖林发
%A 彭建新
%A 唐〓皇
%A 张建仁
%J 长安大学学报(自然科学版)
%D 2018
%X 为探究锈蚀RC梁弯剪加固前后的力学行为，通过外加恒电流加速腐蚀的方法制作7根锈蚀梁，进行锚贴钢板弯剪加固后受弯试验，分析保护层厚度、二次锈蚀以及弯剪加固对试验梁的变形、应变以及承载力的影响。在此基础上，利用Combin39单元考虑钢筋与混凝土的黏结退化，对加固梁进行有限元数值模拟，并将变形、应力的计算值与试验值进行比较分析。结果表明：弯剪加固能有效提高锈蚀梁刚度以及承载力，二次锈蚀和保护层厚度对早期刚度的影响较小；各片试验梁加固前的承载力相差较大，经弯剪加固后，其承载力较为接近；二次锈蚀对加固梁的影响主要体现在锈蚀程度和不均匀性，锈蚀不均匀性会改变破坏形态并影响其使用性能；刚度的退化以及极限承载力的降低主要受锈蚀率影响，而保护层的作用较小；加固前后梁的应变基本表现为线性趋势，保护层厚度对中性轴高度的影响较弱；锈蚀严重时锚固作用较弱，导致梁底应变略有滞后，中性轴高度降低，而轻微锈蚀则能使钢板性能更好地发挥；基于黏结滑移降低系数所建立的有限元模型能够较好地模拟其试验值。<br>In order to explore the mechanical behavior of corroded RC beam before and after flexural and shear strengthening, 7 corroded beams produced by applying constant current accelerated corrosion method were subjected to bending test after flexural and shear strengthening by bolting steel plates，and effects of the thickness of concrete cover, the secondary corrosion and flexural and shear strengthening on the deformation, strain and bearing capacity of test beams were analyzed. On this basis, the bond degradation of reinforcement and concrete was considered by adopting Combin39. Finite element numerical simulation for the strengthened beams were carried out, and the deformation and stress of model were compared with the experimental results. The results show that the flexural and shear strengthening can effectively improve the stiffness and bearing capacity of corroded beams, the secondary corrosion and the thickness of concrete cover had little influence on stiffness in early period. The difference of bearing capacity of the test beam before reinforcement is larger, but after the flexural and shear strengthening, the differences become relatively close. The main effects of the secondary corrosion on reinforced beams are corrosion degree and inhomogeneity which may change the failure mode and affect performance. The degradation of stiffness and reduction of the ultimate bearing capacity are mainly influenced by corrosion rate, while the protective layer has little influence on it. The strain of front and back beams before and after reinforcement is basically presented as linear trend, and the impact of thickness of protective layer on the neutral axis is weak. Weak anchoring effect caused by severe corrosion leads to a slight lag of the strain at the botto
%K 桥梁工程
%K 锈蚀RC梁
%K 有限元法
%K 锚栓钢板
%K 弯剪加固
%K 二次锈蚀&lt
%K br&gt
%U http://zzszrb.chd.edu.cn/oa/DArticle.aspx?type=view&id=10