聚酰胺热熔胶水泥砂浆的基本性能研究

Study on Basic Performance of Cemenl Mortar with Polyamides (PA) Hot-melt Adhesive

形状记忆合金(SMA)驱动下热熔胶水泥基材料具有优良的自修复能力。本文对聚酰胺热熔胶水泥砂浆(PA砂浆)的工作性能、力学性能和耐久性能以及处于多次热循环条件下PA砂浆的力学性能及耐久性能进行了研究。结果表明,体积掺量1%、3%和5%热熔胶的掺入没有降低砂浆的工作性能,反而有略微的提升;随聚酰胺(PA)掺量的增加,砂浆的抗压强度和抗渗性能略有下降,而抗折强度随掺量的增加先增后减;热循环环境中PA水泥砂浆的力学性能与耐久性能都得到了很大的提升,说明PA水泥砂浆在常温马氏体状态、具有预应变的SMA的驱动下具备反复修复水泥基裂缝的潜力。

Recent researches results show that, when driven by shape memory ally（SMA）, hot-melt adhesive have good self-healing properties. In this article, the effects of adding PA hot-melt adhesive on the properties of cement mortar,such as working performance, macroscopic mechanical properties and durability were investigated. And thermal properties of hot-melt adhesive contained cement mortar were also studied. Experimental results show that hot-melt adhesive can improve the workability of motar, and the promotion effect will be enhanced by the increase of hot-melt adhesive dosage.However, the addition of hot-melt adhesive will lead to the degradation of compressive strength and durability. Moreover,the appropriate content of the hot-melt adhesive（Vf5%） can considerably improve the flexural strength of specimens. In contrast to ordinary cement-based materials, macroscopic mechanical properties, especially toughness, and durability of specimens containing hot-melt adhesive are greatly enhanced after being exposed to thermal cyclic environments. So a conclusion can be drawn that PA hot-melt adhesive may repair crack in cementitious materials repeatedly coupled with SMA.