Abstract

Co-Fe-Mg-Al quaternary hydrotalcite-carbon nanotube composites (LDH-CNT composites) were prepared by co-precipitation method and blended into concrete. Universal testing machine and SHPB testing device were used to carry out static and dynamic tests on LDH-CNT concrete specimens with different LDH-CNT additions (0, 0.25 wt.%, 0.5 wt.%), and the dynamic constitutive equation was obtained according to the dynamic stress-strain curve. Results show that compared with ordinary concrete, the compressive strength and toughness of LDH-CNT concrete have been greatly improved. When the LDH-CNT composites content is 0.5 wt.%, the strength and toughness are increased by 10.8% and 16.3%, respectively; The dynamic compression mechanical properties of LDH-CNT concrete show a significant strain rate effect, and the impact compression mechanical parameters increase with the increase of the maximum strain rate. In the strain rate range of 10°∼10²s⁻¹, the theoretical curve and the measured curve fit better, and the constitutive equation can describe the dynamic mechanical response of LDH-CNT concrete.

摘要

采用共沉淀法制备Co-Fe-Mg-Al四元水滑石-碳纳米管复合材料（LDH-CNT复合材料）并掺入混凝土中。利用万能试验机和SHPB试验装置对不同LDH-CNT添加量（0、0.25wt.%、0.5wt.%）的LDH-CNT混凝土试件进行静态和动态试验，得到动态本构方程动态应力应变曲线。结果表明，与普通混凝土相比，LDH-CNT混凝土的抗压强度和韧性都有很大提高。当LDH-CNT复合材料的含量为0.5 wt.%时，强度和韧性分别提高了10.8%和16.3%；LDH-CNT混凝土的动态压缩力学性能表现出显着的应变率效应，冲击压缩力学参数随着最大应变率的增加而增加。在应变率范围 10°∼10² s ^-1，理论曲线与实测曲线拟合较好，本构方程可以描述LDH-CNT混凝土的动态力学响应。