Abstract：
In order to achieve effective monitoring of concrete structures for sound structural health, the addition of carbon nanotubes (CNTs) into cementitious materials offers a promising solution for fabricating CNT-modified smart concrete with self-sensing ability. This study investigated the influences of CNT dispersion method, water/cement (W/C) ratio, and concrete constituents on the piezoelectric properties of CNT-modified cementitious materials. Three CNT dispersion methods (direct mixing, sodium dodecyl benzenesulfonate (NaDDBS) and carboxymethyl cellulose (CMC) surface treatment), three W/C ratios (0.4, 0.5, and 0.6), and three concrete constituent compositions (pure cement, cement/sand, and cement/sand/coarse aggregate) were considered. The experimental results showed that CNT-modified cementitious materials with CMC surface treatment had valid and consistent piezoelectric responses to external loading. The piezoelectric sensitivity improved significantly with increased W/C ratio and reduced progressively with the addition of sand and coarse aggregates.
摘要：
为了实现对混凝土结构健康的有效监测,在胶凝材料中添加碳纳米管（CNT）为制造具有自感知能力的CNT改性智能混凝土提供了有希望的解决方案。本研究考察了CNT分散方法的影响，水/水泥（W/C）比，和混凝土成分对CNT改性胶凝材料压电性能的影响。三种CNT分散方法（直接混合，十二烷基苯磺酸钠（NaDDBS）和羧甲基纤维素（CMC）表面处理），三个W/C比（0.4、0.5和0.6），和三种混凝土组成成分(纯水泥，水泥/砂,和水泥/砂/粗骨料)被考虑。实验结果表明，经过CMC表面处理的CNT改性胶凝材料对外部载荷具有有效且一致的压电响应。随着W/C比的增加，压电灵敏度显着提高，随着沙子和粗骨料的添加，压电灵敏度逐渐降低。
