This study assessed the electrical resistance of smart ultra-high-performance concrete types (S–UHPCs) in the compressive and tensile zones of the flexural specimens subjected to four-point bending tests. The investigated S–UHPCs included a normal ultra-high-performance concrete (UHPC) (M1) integrated with fine steel slag aggregates (FSSAs) (M2) and a UHPC composed of multiwall carbon nanotubes and FSSAs (M3). The electrical resistance of these S–UHPCs remained relatively stable up to the limit of proportionality followed by a significant decrease. The suitable interelectrode distances for electrical resistance change measurements of the S-UHPC beam (100 × 100 × 400 mm) were found to be 30:50:30 mm. Moreover, M2 demonstrated the highest stress sensitivity coefficient in the deflection hardening region (SSC) at both tensile and compressive zones, with values of −4.29 and −1.20 %/MPa, respectively. The SSC for M2 in the flexural–tensile zone was 3.58 times greater than that in the flexural–compressive zone.

中文翻译：

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智能超高性能混凝土梁弯曲下的机电响应：填料类型和电极间距的影响


本研究评估了智能超高性能混凝土类型 (S-UHPC) 在经过四点弯曲测试的弯曲样本的压缩和拉伸区域中的电阻。研究的S-UHPC包括与细钢渣骨料（FSSA）（M2）集成的普通超高性能混凝土（UHPC）（M1）和由多壁碳纳米管和FSSA组成的UHPC（M3）。这些 S-UHPC 的电阻在达到比例极限时保持相对稳定，然后显着下降。 S-UHPC 梁 (100 × 100 × 400 mm) 电阻变化测量的合适电极间距离为 30:50:30 mm。此外，M2 在拉伸和压缩区域的挠曲硬化区域 (SSC) 中表现出最高的应力敏感系数，值分别为 -4.29 和 -1.20 %/MPa。 M2在弯曲-拉伸区的SSC是弯曲-压缩区的3.58倍。