Perceka Wisena, Liao Wen-Cheng, Wang Yo-de
Department of Civil Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
Materials (Basel). 2016 Apr 1;9(4):264. doi: 10.3390/ma9040264.
Addition of steel fibers to high strength concrete (HSC) improves its post-peak behavior and energy absorbing capability, which can be described well in term of toughness. This paper attempts to obtain both analytically and experimentally the efficiency of steel fibers in HSC columns with hybrid confinement of transverse reinforcement and steel fibers. Toughness ratio (TR) to quantify the confinement efficiency of HSC columns with hybrid confinement is proposed through a regression analysis by involving sixty-nine TRs of HSC without steel fibers and twenty-seven TRs of HSC with hybrid of transverse reinforcement and steel fibers. The proposed TR equation was further verified by compression tests of seventeen HSC columns conducted in this study, where twelve specimens were reinforced by high strength rebars in longitudinal and transverse directions. The results show that the efficiency of steel fibers in concrete depends on transverse reinforcement spacing, where the steel fibers are more effective if the spacing transverse reinforcement becomes larger in the range of 0.25-1 effective depth of the section column. Furthermore, the axial load-strain curves were developed by employing finite element software (OpenSees) for simulating the response of the structural system. Comparisons between numerical and experimental axial load-strain curves were carried out.
在高强度混凝土（HSC）中添加钢纤维可改善其峰值后性能和能量吸收能力，这可以用韧性来很好地描述。本文试图通过分析和实验来获得在横向钢筋和钢纤维混合约束的HSC柱中钢纤维的有效性。通过对69个无钢纤维HSC的韧性比（TR）和27个横向钢筋与钢纤维混合的HSC的韧性比进行回归分析，提出了用于量化混合约束HSC柱约束效率的韧性比（TR）。通过本研究中对17根HSC柱进行的压缩试验进一步验证了所提出的TR方程，其中12个试件在纵向和横向均采用高强度钢筋加固。结果表明，混凝土中钢纤维的有效性取决于横向钢筋间距，在截面柱有效深度的0.25 - 1范围内，横向钢筋间距越大，钢纤维越有效。此外，通过使用有限元软件（OpenSees）来模拟结构系统的响应，绘制了轴向荷载 - 应变曲线。对数值和实验轴向荷载 - 应变曲线进行了比较。
