Use of hollow cold-formed steel (CFS) sections has gained popularity in the construction of light industrial and commercial structures. However, their overall load carrying capacity under flexure can be severely affected due to the possible buckling failure modes. Addition of concrete as an infill material for hollow CFS sections can significantly improve their overall performance by resisting their inward local buckling. In this paper, the effectiveness of self-compacting concrete (SCC) as an infill material for hollow channel sections (HCS) is investigated under flexure. In total, nine full-scale hollow channel sections with and without SCC infill are tested to understand the effect of different parameters namely (i) width to depth ratio, (ii) section thickness, and (iii) developed length. In addition, a detailed nonlinear finite element (FE) modeling was performed using the software ABAQUS. Moreover, an analytical investigation was performed to determine the ultimate moment capacity of SCC infilled sections using the strain compatibility procedure. Test results revealed that the addition of SCC infill helped in increasing the ultimate moment resistance by more than 100% when compared to the specimens with no infill. Moreover, the local buckling resistance of HCS is significantly improved due to the addition of SCC infill. The validated analytical and finite element models were used for performing an extensive parametric investigation.

中文翻译：

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自密实混凝土填充对空心通道截面弯曲行为的影响：实验和数值研究

空心冷弯型钢 (CFS) 型材的使用在轻工业和商业结构的建造中越来越受欢迎。然而，由于可能的屈曲失效模式，它们在弯曲下的整体承载能力会受到严重影响。添加混凝土作为空心 CFS 截面的填充材料可以通过抵抗它们的向内局部屈曲来显着提高其整体性能。在本文中，自密实混凝土 (SCC) 作为空心槽截面 (HCS) 填充材料的有效性进行了研究。总共测试了九个带有和不带有 SCC 填充的全尺寸空心通道截面，以了解不同参数的影响，即 (i) 宽度与深度比、(ii) 截面厚度和 (iii) 展开长度。此外，使用 ABAQUS 软件进行了详细的非线性有限元 (FE) 建模。此外，还进行了一项分析研究，以确定使用应变相容性程序的 SCC 填充部分的极限弯矩能力。测试结果表明，与没有填充物的试样相比，添加 SCC 填充物有助于将极限力矩阻力提高 100% 以上。此外，由于 SCC 填充物的加入，HCS 的局部抗屈曲性能得到显着提高。经过验证的分析和有限元模型用于执行广泛的参数研究。测试结果表明，与没有填充物的试样相比，添加 SCC 填充物有助于将极限力矩阻力提高 100% 以上。此外，由于 SCC 填充物的加入，HCS 的局部抗屈曲性能得到显着提高。经过验证的分析和有限元模型用于执行广泛的参数研究。测试结果表明，与没有填充物的试样相比，添加 SCC 填充物有助于将极限力矩阻力提高 100% 以上。此外，由于 SCC 填充物的加入，HCS 的局部抗屈曲性能得到显着提高。经过验证的分析和有限元模型用于执行广泛的参数研究。