锈胀开裂后钢筋混凝土粘结滑移本构关系研究

BOND-SLIP RELATIONSHIP BETWEEN CORRODED STEEL BARS AND CONCRETE

采用外加电流加速钢筋锈蚀的方法 ,控制试件表面不同锈胀裂缝宽度。在钢筋开槽、内贴应变片的半梁式粘结试验的基础上 ,根据实测结果和理论分析 ,获得不同试件锚固长度内粘结应力及钢筋混凝土相对滑移的分布规律 ,推导出τ s关系沿锚固长度的变化规律 ,从而提出了不同锈胀程度下 ,反映这种变化规律的位置函数 ψ (x) ,建立考虑锚固位置影响的锈后钢筋混凝土粘结滑移本构关系 ,为锈后钢筋混凝土构件的有限元分析计算提供依据。

In this paper,half?beam tests are carried out to study the influence of steel bar corrosion and cracking widths on the bond behavior of the reinforced concrete.The bond behavior of the reinforced concrete in noncorrosion,precrack stage,crack initial stage,and post?crack stage is studied.The stages of corrosion are achieved by impressing the direct current on test bars.These bars are instrumented with the strain gauge placed in a machined axial cavity.The distribution of the bond stress and relative slip along the anchorage length of a corroded bar is calculated based on the test results.The test results have shown that the bond strength decrease rapidly while the expansion cracking occurred ,and the bond?slip relationship at different position along the steel bar is varied.