Taking Fengfeng coal field as an example, the paper applies the fuzzy mathematics principle to the strength of karst runoff zone of Minmetals field partition. The frequency statistics method is adopted to define the membership degree, elevation, single well water inflow, karst rate, and hydration group classification. At the same time, considering the influence of the ionic concentration of karst water runoff intensity, the fuzzy comprehensive evaluation method is used for the calculation, and

more »

... he results show that the strength of the karst runoff zone will affect the safety of mining. Karst water runoff intensity is proportional to the concentration of the ions. The relationship between runoff intensity and single well water inflow is most obvious. The biggest water inflow of the single well is in a strong runoff zone, and in a weak runoff zone it is very small, which provides decision basis for mine safety production planning. Minmetals is located in the Ordovician limestone strong runoff belt of Gushan east side, thus constituting a serious threat for deep coal seam mining. The research in this paper provides a theoretical basis for Minmetals deep seam mining from the weakest runoff.