Evaluation system of grouting effect of coal seam floor based on TOPSIS-RSR method with combination weighting

Karst aquifer in the floor is severe theat to deep coal seam mining. Regional ground pre-grouting is an effective means to prevent floor water inundation. How to use the data of the drilling and grouting construction process to evaluate the grouting effect objectively is an urgent problem to be solved. Taking the grouting project of D3, D10, D11, and D12 surface hole groups in the 1111 mining area of Qiuji Coal Mine in Shandong Province as the background, the comprehensive evaluation system of the grouting effect was established by taking drilling fluid leakage, final grouting pressure, permeability coefficient and unit grouting amount as evaluation indexes. An improved analytic hierarchy process (AHP method) combined with the subjective and objective comprehensive weighting method of CRITIC accurate weighting method is proposed. The arithmetic average method, geometric average method, and eigenvalue method are used to improve AHP method. Based on the combination weighting method, a comprehensive evaluation model of the grouting effect based on TOPSIS sorting and WRSR auxiliary grading is established. The relative distance is used to optimize the defect of TOPSIS relative nearness degree and improve the data processing results. The evaluation results are converted into visual zoning maps and compared with water inflow revealed by underground drilling after grouting. The results show that the evaluation method is reasonable and consistent with the field actual results. © 2024 Editorial Office of Journal of Mining and Strata Control Engineering. All rights reserved.