二次受力下自密实混凝土加固RC梁受弯性能研究

发布时间：2018-03-21 19:30

本文选题：自密实混凝土　切入点：增大截面法加固　出处：《工程力学》2015年04期 　论文类型：期刊论文

【摘要】：为模拟实际工程中加固构件的真实承载能力,实验在原混凝土构件持续受荷状态下,采用自密实混凝土对构件进行加固、养护。共进行了7根二次受力下自密实混凝土加固钢筋混凝土梁和2根对比梁的受弯性能试验,研究了不同初始受力水平、不同加固厚度及不同界面处理方式对加固钢筋混凝土梁抗弯承载力和截面刚度的影响。试验量测了构件裂缝分布形态、荷载-挠度曲线、钢筋应变发展规律等。结果表明:采用自密实混凝土加固钢筋混凝土梁,能有效地提高钢筋混凝土梁的抗弯承载力、截面刚度等性能;二次受力下自密实混凝土加固梁抗弯承载力随着初始受力水平的增大而降低。在试验结果的基础上,基于平截面假定,提出了二次受力下自密实混凝土加固梁钢筋滞后应变及抗弯承载力计算式,计算结果与试验结果吻合良好。
[Abstract]:In order to simulate the real load-bearing capacity of the strengthened members in practical engineering, the self-compacting concrete is used to reinforce the members under the condition of continuous loading of the original concrete members. The flexural behavior tests of 7 reinforced concrete beams strengthened with self-compacting concrete and 2 contrast beams under secondary loading were carried out, and different initial loading levels were studied. The effects of different strengthening thickness and interface treatment on flexural bearing capacity and section stiffness of reinforced concrete beams were studied. The crack distribution and load-deflection curves of reinforced concrete beams were measured. The results show that self-compacting concrete can effectively improve the flexural bearing capacity and section stiffness of reinforced concrete beams. The flexural capacity of self-compacting concrete strengthened beams decreases with the increase of initial loading level. Based on the experimental results and the assumption of plane section, the bending capacity of self-compacting concrete strengthened beams decreases with the increase of initial loading level. A formula for calculating the delayed strain and flexural bearing capacity of reinforced concrete beams strengthened by self-compacting concrete under secondary loading is presented. The calculated results are in good agreement with the experimental results.
【作者单位】：福州大学土木工程学院;
【基金】：国家自然科学基金项目(51378126) 福建省科技厅产学合作重大专项项目(2012H6011)
【分类号】：TU375.1

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