1、翻译部分英文原文Risk assessment of oor water inrush in coal mines based on secondary fuzzy Yi Wang*, Weifeng Yang, Ming Li, Xi Liu School of Resources and Geosciences, China University of Mining and Technology, Xuzhou Jiangsu 221116, China Abstract: A secondary fuzzy comprehensive evaluation system is const
2、ructed to evaluate the risk of oor water invasion in coal mines. Four rst-grade indices and 13 second-grade indices are determined based on the principles of scienticity, rationality, operability and representative by using fuzzy mathematics theory. Each index is quantitatively graded according to v
3、e risk grades using fuzzy statistical method and expert evaluation method, and the membership degree of every index is constructed. The weight of every index is rationally distributed by analytic hierarchy process (AHP). Evaluations of engineering practice are carried through with hydrogeological da
4、ta of six mining faces in China. The satisfying evaluation results are consistent with engineering practice.Key words:Floor water inrush；Secondary fuzzy comprehensive evaluation；Analytic hierarchy process (AHP)；Membership degree；Weight1. IntroductionAccording to the latest statistics from Chinese co
5、al mines in 2000 to 2011, it is found that mine water accidents frequently occur, resulting in huge casualties and economic loss (Table 1). These greatly endanger the life of miners and delay the development of coal mine projects. Mining operations in China are often threatened by frequent water inr
6、ushes from conned karst aquifers, affecting the safe coal extractions. Evaluating and solving the problem of mining safety has practical signicance in coal extractions. The research of water inrush has been popular in recent years with methods varied. Dumpleton et al. used 3-D visualization and pred
7、ictive modeling to evaluate the risk of mine water inrush in south Nottinghamshire 1. Hodlur et al. showed a statisticalhydrogeological model to evaluate mining water hazards 2. Zhang presented the water inrush mechanism and applied the nite element method coupled with stress-dependent permeability
8、to predict water inrush, proposing some technical measures to improve mine design and safety 3. Kong used a theory of seepage instability to estimate the harmfulness of water inrush from a coal seam oor in a particular coal mine of the Mining Group, Xuzhou 4. Han et al. presented the methods of stra
9、ta mechanics and nite element analysis to describe the mechanismofmine water inrush through a fault from the oor 5. Bukowski proposed a risk assessment system to analyze water hazard, based on the factors of inow intensity, the amount of suspended material contained in the water owing into the shaft
10、, the proportion of water-bearing formations in the vertical prole, the condition of the shaft lining and safety pillar, and the history of the shaft 6. Chen applied Fault Tree Analysis (FTA) to analyze the hazard common source of mine water inrush 7. Some of these simplify conditions or factors and
11、 fail to profoundly reveal the quantifying relation between water inrush and its affecting indices, while others exist some limitations despite their uniqueness to manage the problem of water inrush. The method of comprehensive evaluation for risk of oor water inrush proposed based on the theory of
12、fuzzy mathematics fully takes into consideration the main indices affecting water inrush with the advantages from qualitative to quantitative and of high accuracy and universal application.2. Design of comprehensive evaluation index systemWith reference to years representative researches on oor wate
13、r inrush in many countries, the experts abundant research experience and methods 46,821 were used. So based on the scienticity, rationality, operability and representative of the evaluation index system, in this paper four rst-grade indices and 13 second-grade indices are put forward through the ana
14、lytic hierarchy process (AHP). The evaluation index system of oor water inrush risk consists of four parts on the whole, include: (1) The geological structure index is the primary index controlling the occurrence of water inrush, including fault density, fault water transmitting ability, fracture de
15、velopment degree. (2) The hydrogeology index reects hydrogeology conditions of the aquifer and its relative position to runoff, including conned water pressure, aquifer water yield property, karst development degree and the strong water source recharge. (3) The oor aquifuge index is the only index t
16、o obstruct the occurrence of water inrush, including aquifuge thickness, strength and integrity; (4) The mining size index is an induction to water inrush, including mining thickness, mining depth and inclined length of the mining face.The evaluation index system of water inrush risk from coal oor is as follows (Fig. 1). The index set is divided into two grades by us: the rst-grade index set is:U=(U1, U2, U3, U4)
