Abstract This work presents an experimental study performed to investigate the influence of the width and size of the specimen on the fracture response of concrete notched beams. Twenty-eight beams with six cross-sections has been tested using a three-point bending (TPB) test setup, which is designed according to the draft of a report developed by Joint ACI/ASCE 446 Technical Committee. Two depths (70 mm and 150 mm) and three widths (35 mm, 70 mm and 150 mm) of the beam are considered. 3D digital image correlation (DIC) is employed for 18 specimens. The load-deflection response obtained from DIC is compared with the load-deflection response obtained from the readings of two linear variable displacement transformers (LVDT). Load responses, peak loads, strain profiles, and failure modes of TPB tests are presented and discussed. The authors observe that a potential width effect is combined with the well-known size effect. In addition, the evaluation of the fracture energy from the load response might be influenced by the width of the beam. Finally, the strain profiles along the notched cross-section obtained from DIC suggest that the evaluation of the fracture energy from the load response might be misleading.

中文翻译：

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试件宽度对混凝土缺口梁断裂响应的影响

摘要 这项工作提出了一项试验研究，以研究试样的宽度和尺寸对混凝土缺口梁断裂响应的影响。使用三点弯曲 (TPB) 测试装置测试了具有六个横截面的 28 根梁，该装置是根据联合 ACI/ASCE 446 技术委员会制定的报告草案设计的。考虑了梁的两种深度（70 毫米和 150 毫米）和三种宽度（35 毫米、70 毫米和 150 毫米）。18 个样本采用 3D 数字图像相关 (DIC)。将从 DIC 获得的负载挠度响应与从两个线性可变位移变压器 (LVDT) 的读数中获得的负载挠度响应进行比较。介绍和讨论了 TPB 测试的载荷响应、峰值载荷、应变曲线和失效模式。作者观察到潜在的宽度效应与众所周知的尺寸效应相结合。此外，根据载荷响应对断裂能的评估可能会受到梁宽度的影响。最后，从 DIC 获得的沿缺口横截面的应变分布表明，根据载荷响应对断裂能量的评估可能具有误导性。