1、翻译部分Analysis on rock burst danger when fully-mechanized caving coal face passed faultwith deep miningChen Xuehua a, Li Weiqing b, Yan Xianyang baCollege of Resources and Environment Engineering, Liaoning Technical University, Fuxin, ChinabDongtan coal Mine, Yanzhou Coal Mining Company Limited, Zouch
2、eng, ChinaAbstractWhen fully-mechanized caving face passed fault, rock burst accidence easily occurred. The SOS microseismmonitoring system was applied to monitor the microseismic activities all time occurred in the coaland rock mass near the fault area. Variation features of microseismic energy rel
3、easing and microseismicfrequency were analyzed. Numerical simulation method was used to research the abutment stress distributionwhen coal face passed fault, which was compared with microseism occurrence rules. When thecoal face approached to fault, the abutment stress increases gradually, so the hi
4、gh stress would accumulatenear the fault region. When the coal face left fault, the abutment stress decreased. The SOS microseismmonitoring results showed that microseismic activity in the fault area had a high instability.When the coal face neared to the fault, total energy value and frequency rele
5、ased by the microseism steadilyincreased. The maximum energy peak value also had the tendency to rapidly increase. Before thestrong shock occurred, there was a period of weak seismic activity. The weak seismic activity showedenergy accumulation for strong shock, which can be used to forecast the dan
6、ger of rock burst.Keywords:Rock burst;Microseism monitoring system;Fault;Numerical simulation1.IntroductionThe equipment will be damaged, and people will be injuredwhen rock burst occurs, which is one of the biggest disasters tomine safety. With the expansion of mining and tunneling, the conditionof
7、 mining face will be complex, the mining activity in thecoal pillar and adjacent to coal pillar is inescapability. During themining progress in deep coal seam, influenced by the fault structure,the mine pressure appears very violently around the excavationface, the sound of mine quake becomes larger
8、, and the numberof mine quake becomes more and more. Research on the rock burstoccurrence rule under the complex geological structure is verynecessary to safety production.The domestic and oversea scholars (Su and Li, 2008; Lu et al.,2008; Li et al., 2008a,b,c; Lu et al., 2007; Gou et al., 2007; Jia
9、nget al., 2006; Dou and He, 2004; Song et al., 2004; Caim Kaiserand Martin, 2001; Meng et al., 2001; Huang and Gao, 2001; Panet al., 1998) have studied the mechanism of fault activity inducingrock burst, and the microseismic law of rock burst portent. Theslide destabilization characteristic of surro
10、unding rock, the stressdistribution and change rules, and rock burst occurrence mechanismwere researched by the viewpoint of the fault upper walland lower wall, coal seam roof and floor, and fault fractured zoneand coal mechanics character in the relevant document. The researchon rock burst danger o
11、f fully-mechanized caving coal facepassed fault is relevantly less.The No. 14310 coal face passing the No. NF6 fault in the Dongtanmine was acted as research object. The relevant mathematicalmodel was used to research the rock burst mechanism induced bythe activity of regional surrounding rock. Micr
12、oseismic law of coalface passed fault was explored, which can guide the forecast andprevention of rock burst.2.Microseismic activity monitoring and change rules in faultregion when coal face excavated2.1. Change rules of microseismic hypocenterThe Polish SOS microseismic monitoring system was used i
13、n theDongtan mine, and the microseismic activity was monitored andlocated in real time. The change of microseismic hypocenter positionand energy was recorded when the coal face passed the No.NF6 fault. The monitoring result about concentrative and violentdistribution of microseismic hypocenter was a
14、nalyzed.Illustrated as Fig. 1, all kinds of the points showed microseismichypocenter position, the different shapes showed different microseismicgrades, and the black short line showed the excavationposition of coal face. According to the monitoring result, the microseismichypocenter changed along w
15、ith the excavation progress. Inthe vertical section, the hypocenter changed obviously. When thecoal face was far from the fault, the excavation was little influenceon fault activity, and the microseismic hypocenter mainly distributedin the front of coal face and on the goaf.In July 26, 2010, the dis
16、tance of coal face far from fault was62 m, the mine pressure emergence near coal face enhanced, thetimes of microseismic occurrence increased obviously, but themicroseismic grade was small. At this time, microseismic beganto appear near fault, which showed the fault activity was influencedby the coal face excavation (see Fig. 1a).Fig. 1. Distribution change of microseismic hypocenter along with coal face excavation in vertical section.Along with coal fac
