不同搅拌方式下多壁碳纳米管对UHPC力学性能的影响研究

Study on the influence of MWCNTs on UHPC mechanical properties under different mixing methods

研究双卧轴搅拌和振动搅拌2种搅拌方式对掺入多壁碳纳米管(MWCNTs)的超高性能混凝土(UHPC)拌合物性能和力学性能的影响,结果表明,掺入MWCNTs后,UHPC的拌合物性能在双卧轴搅拌时明显降低,在振动搅拌时变化不大;采用双卧轴搅拌和振动搅拌,掺入MWCNTs均能一定程度提高UHPC的轴心抗压、弹性极限轴心抗拉及抗弯性能,且振动搅拌的效果更优;采用振动搅拌,MWCNTs掺量为0.05%时,与空白组相比,UHPC的轴心抗压、轴心抗拉及抗弯强度分别提高了3.0%、30.0%、38.0%,弯曲韧性指数I_(5)、I10、I_(20)分别增大了50.8%、71.6%、85.6%,弯曲韧性比提高了63.7%,MWCNTs具有很好的增强增韧效果。

The study investigates the effects of two mixing methods,dual-shaft mixing and vibration mixing,on the performance and mechanical properties of ultra-high-performance concrete(UHPC)incorporating multi-walled carbon nanotubes(MWCNTs).The results indicate that the workability of UHPC significantly decreases when mixed with dual-shaft mixers after the addition of MWCNTs,while it remains relatively unchanged with vibration mixing.Both dual-shaft and vibration mixing methods can improve the compressive strength,tensile strength,and flexural performance of UHPC to some extent when MWCNTs are incorporated,with vibration mixing showing superior results.When using vibration mixing and incorporating 0.05%MWCNTs,the compressive strength,tensile strength,and flexural strength of UHPC increased by 3.0%,30.0%,38.0%respectively compared to the control group.The flexural toughness indices I_(5),I_(10),I_(20)increased by 50.8%,71.6%,85.6%respectively,and the flexural toughness ratio improved by 63.7%.MWCNTs have shown excellent reinforcing and toughening effects.