Comprehensive Evaluation and Decision for Goaf Based on Fuzzy Theory in Underground Metal Mine

Abstract

In underground metal mines, goaf brings huge safety risks. It is an important part of mine to evaluate goaf stability and determine the best goaf handling measures. However, the evaluation and decision are often separated; they need to be unified. Meanwhile, stability evaluation and decision for goaf are a complex system engineering of rock masses in underground mining, and subjectivity exists in the evaluation and decision process. Under these conditions, it is necessary to minimize subjectivity, and the results of stability evaluation also need to be considered comprehensively in determining handling measures. In this paper, the fuzzy theory was adopted based on the fact that the goaf stability evaluation and handling measure decision were fuzziness. Firstly, the goaf stability model was established by a two-layer fuzzy comprehensive evaluation. It took into account 12-factor indexes of goaf with engineering empirical approaches and divided them into 3 categories according to their engineering categories. The model improved the applicability of the goaf stability evaluation results, and the results were the basis for goaf handling measures as well. Secondly, a decision model of the goaf handling measures was established by multiobjective fuzzy optimization. It consisted of five goaf handling measures and five evaluation indexes. The model provided a comprehensive decision and optimal scheme for goaf handling. Two models were also applied to the Paishanlou gold mine and achieved a good handling result. The practical application showed that the two models were feasible.

Stability Evaluation of the Goaf Based on Combination Weighting and Cloud Model

“…They developed a stability analysis model of group goaf based on D-S evidence theory's multisource information fusion. He et al [7] created the goaf stability model by using the double-layer fuzzy comprehensive evaluation method. An improved TrAdaBoost algorithm based on transfer learning theory was proposed by Qin et al [8] for predicting goaf stability.…”

Stability evaluation of goaf in closed mining area: a case study of Sanhejian closed mining area in Jiangsu Province, China

“…Liu (Liu et al 2022), combined with numerical simulation results, predicted the subsidence deformation of the mine under thick loose layers using grey relational analysis, nding that coal thickness has the greatest impact on maximum settlement, while cohesion is the smallest factor. He (He et al 2022) established a goaf stability model using fuzzy comprehensive evaluation and determined the treatment method for the goaf based on the results of this model. Wu (Wu et al 2018) similarly conducted a fuzzy comprehensive evaluation of the ground stability of the goaf and effectively validated it based on actual site conditions.…”

Study on Stability Evaluation of Goaf Based on AHP and EWM—Taking the Northern New District of Liaoyuan City as an Example

“…These hazards are not only a cause of property losses but also pose a serious threat to the safety of residents. It is crucial to note that these hazards can be life-threatening [3][4][5][6] . In addition, the depletion of underground resources makes the ecological environment on the surface highly vulnerable to floods or surface water caused by the exploitation of the underground 7 .…”