在这项工作中,研究了不同外径和比表面积的多壁碳纳米管(MWCNT1,MWCNT2和MWCNT3)对水泥砂浆力学性能和电性能的影响。使用不同浓度的MWCNT(0.05、0.10和0.15%),其有效分散通过使用表面活性剂的超声波机(以160W功率和24kHz频率进行40分钟)进行。复合材料的生物二氧化硅含量为水泥重量的10%,但没有。在固化的第7天和第28天进行压缩强度测试。与对照样品的结果相比,不使用生物二氧化硅制备的样品的7天抗压强度增加(MWCNT1为6.4%,MWCNT2为7.4%,MWCNT3为10.8%),使用生物二氧化硅的人也是如此(MWCNT1为6.7%,MWCNT2为29.2%,MWCNT3为2.1%)。28天样品的抗压强度测试产生以下结果:MWCNT1为21.7%,MWCNT2为3.8%,MWCNT3为4.2%,在不存在生物二氧化硅和8.5%的情况下,12.6%,和6.3%的生物二氧化硅,分别。在用0.1%MWCNT浓度处理的复合材料中观察到压缩强度的最大增加,而在0.05和0.15%浓度的情况下,抗压强度相对较低。由于这些颗粒的高导电性,MWCNT增强的水泥基质获得了电性能。MWCNT浓度为0.05、0.10和0.15wt%对水泥砂浆电性能的影响,特别是水泥砂浆的体积电阻率和压阻特性,在这项工作中进行了研究。在浓度为0.05%时,获得了最低的电阻率值,然后开始增加。获得的结果表明,所有研究的样品都具有压阻特性,并且测量结果导致电阻率分数变化的偏差。
In this work, the effect of multi-walled carbon nanotubes (MWCNT1, MWCNT2, and MWCNT3) with different outer diameters and specific surface areas on the mechanical and electrical properties of cement mortar have been investigated. Various concentrations of MWCNTs were used (0.05, 0.10, and 0.15%), the effective dispersion of which was carried out by an Ultrasonic machine (for 40 min with 160 W power and a 24 kHz frequency) using a surfactant. Composites have been processed with a
biosilica content of 10% by weight of cement and without it. Compressive strength tests were carried out on days 7 and 28 of curing. The 7-day compressive strength of samples prepared without
biosilica increased compared to the result of the control sample (6.4% for MWCNT1, 7.4% for MWCNT2, and 10.8% for MWCNT3), as did those using
biosilica (6.7% in the case of MWCNT1, 29.2% for MWCNT2, and 2.1% for MWCNT3). Compressive strength tests of 28-day specimens yielded the following results: 21.7% for MWCNT1, 3.8% for MWCNT2, and 4.2% for MWCNT3 in the absence of
biosilica and 8.5%, 12.6%, and 6.3% with
biosilica, respectively. The maximum increase in compressive strength was observed in the composites treated with a 0.1% MWCNT concentration, while in the case of 0.05 and 0.15% concentrations, the compressive strengths were relatively low. The MWCNT-reinforced cement matrix obtained electrical properties due to the high electrical conductivity of these particles. The effect of MWCNT concentrations of 0.05, 0.10, and 0.15 wt% on the electrical properties of cement mortar, especially the bulk electrical resistivity and piezoresistive characteristics of cement mortar, was studied in this work. At a concentration of 0.05%, the lowest value of resistivity was obtained, and then it started to increase. The obtained results show that all investigated specimens have piezoresistive properties and that the measurements led to a deviation in fractional change in resistivity.