Impact mechanical properties and pore structure of graphene oxide concrete at high temperature

The high chemical activity, excellent mechanical properties, and dispersibility of graphene oxide (GO) make it an ideal nano reinforcement material for concrete. The test specimen in this paper is ordinary concrete with different dosages of GO. The basic mechanical properties and high temperature impact mechanical properties of the specimens were studied by cube compression test, splitting tensile test and high temperature Split Hopkinson Pressure Bar test. The static compressive strength and dynamic compressive strength of graphene oxide concrete (GOC) with 0.06 wt% GO content increased by 30.0 % and 44.1 %. GO can also alleviate the deterioration effect of high temperature on concrete. The mercury intrusion porosimetry (MIP) experiments on concrete samples deteriorated at different temperatures show that GO can effectively curb the development of harmful pores. X-ray diffraction (XRD) and scanning electron microscopy (SEM) experiments have shown that GO can regulate the growth of cement hydrates and reduce initial defects inside the cement paste. The slow development rate of harmful pores at high temperatures and fewer initial pores are the important reasons for the excellent impact mechanical properties of GOC at high temperatures.