This paper mainly focuses on revealing the hydration mechanism of new cementitious material of filling body through its microstructure analysis. According to the SEM samples preparation, analysis of different age of filling body microstructure and XRD diffraction mapping, the results showed that the hydration products were with large amount of ettringite, followed by C-S-H gel, calcium and silica. The main reason of strength increasing was the ettringite morphology and the hydration process. It was obtained that the hydration products of different activators were mainly the influence factor of strength, on basis of analyzing the microstructure of different activator materials.

Previous studies found that there were some problems when processing goaf by filling method, such as large amount of cement, and high cost. A new type of cementing material was investigated in this study. Its main ingredients was graining blast furnace slag. on the chemical activation, its activities were substantially improved, and the technical parameters of the filling body were markedly ameliorated. Furthermore, the new cementing material complied with the filling cementing material standard of China. The results demonstrated that the new type of cementing material which overcome some traditional shortconmings could be the pottential material for the similar mines which exploit ores by back-filling method.

The purpose of slope stability evaluation was that, according to the slope engineering condition and constraints of mining technology, to study the deformation and failure rule of slope occurred by the change of stress field during the open-pit mining. The main research object of the paper was open-pit slope of one iron mine, for the mechanical parameters of the slope, it was obtained by physical experiments, and the numerical simulation method was used for the stability analysis and evaluation of quaternary soil slope angle and final slope angle. And some measures were proposed for slope stability during construction to ensure safety in production. The research of the paper has certain reference significance for optimization calculation of the soil slope stability