氧化石墨烯改性水泥砂浆断裂性能研究

Study on fracture properties of graphene oxide modified cement mortar

通过带预制切口的三点弯曲梁断裂试验测试了氧化石墨烯(GO)改性水泥砂浆的断裂性能,采用双参数模型分析了GO掺量对改性水泥砂浆断裂参数的影响。结果表明,GO改性水泥砂浆裂缝嘴张开口位移、断裂能、临界应力强度因子等断裂参数均随GO掺量的增加而增加,当GO掺量为0.03%(水泥质量分数)时,较普通水泥砂浆分别提高46.34%、28.11%、48.08%。利用扫描电镜(SEM)表征GO改性水泥砂浆微观结构,发现GO能加强水泥水化产物之间的连接,引导其形成规则有序的结构从而减少应力集中,改性水泥砂浆的断裂性能得到改善。

Fracture properties of graphene oxide(GO)modified cement mortar was investigated by fracture test of three point bend beamwith prefabricated notch.The influence of GO content on the fracture parameters of modified cement mortar was analyzed by two parameter fracture model.The results showed that the fracture parameters such as crack mouth open displacement,fracture energy and critical stress intensity factor of GO modified cement mortar increase with the increase of GO content,when the content of GO is 0.03%(by mass of cement),it was increased by 46.34%,28.11%and 48.08%as compared with the ordinary cement mortar.The microstructure of GO modified cement mortar were characterized by scanning electron microscopy(SEM).The results showed that GO can strengthen the con nection between the hydration products of cement,guide them to form a regular and orderly structure and reduce stress concentration,the fracture properties of modified cement mortar was improved.