Dey Alinda, Valiukas Domas, Jakubovskis Ronaldas, Sokolov Aleksandr, Kaklauskas Gintaris
Department of Reinforced Concrete Structures and Geotechnics, Vilnius Tech University (VGTU), Saulatekio al. 11, 10221 Vilnius, Lithuania.
Laboratory of Innovative Building Structures, Vilnius Tech University (VGTU), Saulatekio al. 11, 10221 Vilnius, Lithuania.
Materials (Basel). 2021 Dec 31;15(1):293. doi: 10.3390/ma15010293.
A bond mechanism at the reinforcement-concrete interface is one of the key sources of the comprehensive functioning of reinforced concrete (RC) structures. In order to apprehend the bond mechanism, the study on bond stress and slip relation (henceforth referred as bond-slip) is necessary. On this subject, experimental and numerical investigations were performed on short RC tensile specimens. A double pull-out test with pre-installed electrical strain gauge sensors inside the modified embedded rebar was performed in the experimental part. Numerically, a three dimensional rib scale model was designed and finite element analysis was performed. The compatibility and reliability of the numerical model was verified by comparing its strain result with an experimentally obtained one. Afterwards, based on stress transfer approach, the bond-slip relations were calculated from the extracted strain results. The maximum disparity between experimental and numerical investigation was found as 19.5% in case of strain data and 7% for the bond-slip relation at the highest load level (110 kN). Moreover, the bond-slip curves at different load levels were compared with the bond-slip model established in CEB-fib Model Code 2010 (MC2010). Overall, in the present study, strain monitoring through the experimental tool and finite element modelling have accomplished a broader picture of the bond mechanism at the reinforcement-concrete interface through their bond-slip relationship.
钢筋与混凝土界面的粘结机理是钢筋混凝土（RC）结构综合性能的关键来源之一。为了理解粘结机理，有必要研究粘结应力与滑移关系（以下简称粘结滑移）。针对这一课题，对短RC拉伸试件进行了试验和数值研究。在试验部分，对在改进的埋入式钢筋内部预先安装了电应变片传感器的双拔出试验进行了研究。在数值方面，设计了一个三维肋尺度模型并进行了有限元分析。通过将数值模型的应变结果与实验获得的结果进行比较，验证了数值模型的兼容性和可靠性。之后，基于应力传递方法，从提取的应变结果中计算出粘结滑移关系。在最高荷载水平（110kN）下，实验与数值研究的最大差异在应变数据方面为19.5%，在粘结滑移关系方面为7%。此外，还将不同荷载水平下的粘结滑移曲线与CEB - fib 2010模型规范（MC2010）中建立的粘结滑移模型进行了比较。总体而言，在本研究中，通过实验工具和有限元建模进行的应变监测，通过其粘结滑移关系，对钢筋与混凝土界面的粘结机理有了更全面的认识。
