The effects of different parameters on the evolution of Out-Of-Plane (OOP) instability in rectangular walls were studied using a validated FEM model. Based on this parametric analysis, a test matrix was designed to experimentally investigate the progression of this mode of failure in rectangular walls. Results of the parametric study were presented within a companion paper, while the experimental observations as well as the numerical versus experimental comparisons are presented in this paper. The wall specimens were tested under in-plane cyclic loading and they exhibited different OOP responses. The development of OOP mechanisms was observed in all tested specimens, albeit with different values of maximum OOP displacement and followed by different types of instability. Progression of OOP deformation was suppressed by other failure modes in all specimens except one which failed due to large OOP displacement and global instability. In this study, the progression of OOP deformation and its relationship with the inelastic strain gradients of the longitudinal reinforcement along the length and height of the specimens are scrutinized and the numerical predictions are compared with the test measurements. The experimental findings regarding the evolution of this mode of failure and the influential parameters are in good agreement with the numerical predictions. However, the onset of OOP deformation typically had a delay in the numerical model when compared to the test results. One of the factors inducing this difference could be the effect of inherent and mostly unmeasurable eccentricities, including material, geometry as well as loading imperfections, which were not included in the model.

中文翻译：

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双重加固结构墙面外失稳的参数研究。第二部分：实验研究

使用验证的有限元模型研究了不同参数对矩形墙内平面外（OOP）不稳定性演变的影响。基于此参数分析，设计了一个测试矩阵来实验研究矩形壁中这种破坏模式的进程。参数研究的结果在随附的论文中介绍，而实验的观察结果以及数值与实验的比较则在本文中介绍。在平面内循环载荷下对壁试样进行了测试，它们表现出不同的OOP响应。在所有被测样品中都观察到OOP机制的发展，尽管最大OOP位移值不同，但随后的失稳类型也不同。除了一个由于大的OOP位移和整体不稳定性而导致失效的试样外，所有试样的OOP变形进展都受到其他失效模式的抑制。在这项研究中，对OOP变形的进展及其与纵向钢筋沿试样的长度和高度的非弹性应变梯度的关系进行了仔细研究，并将数值预测与测试结果进行了比较。关于这种失效模式的演变和影响参数的实验结果与数值预测非常吻合。但是，与测试结果相比，OOP变形的开始通常在数值模型中具有延迟。导致这种差异的因素之一可能是固有的且几乎无法测量的偏心影响，包括材料，