1、翻译部分英文原文A Catastrophe Model of Coal and Gas Delay OutburstL IU Bao x ian, W AN G Ze yun, LIU Li( Department of Civil Const ruction , Xihua University, Chengdu 610039 Sichuan China)Abstract:Catastrophe theory can effectively solve catastrophe problem that can possible appear in continuum system. The
2、mechanism of coal and gas delay outburst is studied w ith catastrophe theory.It is concluded that the delay time of coal and gas delayout burst is produced by the combination of geostresses gas inside coal,physics mechanics characters of coal and external action (explosion).According to the above re
3、search, the way of preventing coal and gas delay outburst is presentedKey words: coal and gas delay outburst ; catastrophe; prevention0 IntroductionCoal and gas delay outburst refers to the outburst not occurred during the explosive extraction at the explosion area, but occurred with in a certain pe
4、riod after the ex plosion.Delay out burst occurred frequently in China and caused substantial losses in life and properties, such as Donglin Coal Mine and Yut ianbaoCoal Mine of Nantong M ining Bureau,Shuijiang Coal Mine of Fuling area,Sanbao Coal Mine of Beipiao Mining Bureau,Tanjia Coal Mine and L
5、iwang-miao Coal Mine of Baisha Mining Bureau,Hongling Coal Mine of Shenyang Mining Bureau ,Liuzhi Mining Bureau and so on.The issue of coal and gas delay out burst was put forward by the scholar of t he for mer Soviet U nion in the 1950s, and it also was studied in China. There are several main idea
6、s about the mechanism of coal and gas delay outburst.(1) The cause of delay outburst is that there is a preparation stage fo r the out burst - releasing of potential energy and crushing of the coal mass. (2) The decisive factor of delay out burst might be that hard coal with relaive high carrying ca
7、pacity exist in new coal-face which continue to accumulate the elastic energy. (3) Delay outburst results from the plastic def ormation under the impact of external force. ( 4) The occurrence of delay outburst is resulted f rom the combined functions of the storage situation and various actions ( in
8、ternal and external factors) during the course of extraction. ( 5)Delay outburst is associated with coal mass pressure relief region. Delay outburst occurs, as it takes some time for outburst with the relatively long pressurerelief region. ( 6) Delay outburst occurs because there is some thick of so
9、ft coal seam. (7) Delay outburst occurs when the creeping gas - containing coal pro ressed f rom the creeping stage II ( stabilizat ionstage) to the accelerated dest ruct ion stage III ( destabilizat ion creeping stage) under the impact of st ressraise after coal mass entered into the creeping stage
10、.In the beginning of 1970s, Catastrophe Theory was founded by Thom, a French mathematician.Catastrophe Theory is a new branch of studying in continuous phenomenon. It can effectively solve catastrophe problem that can possibly appear in continuum system. The main method is that all kinds of phenomen
11、on are summed up to different kind of topological structure and discuss in continuous state character near to all kinds of critical point s.Catastrophe Theory is especially applicable to study the system which internal actions are not known. In recenty ears, many scholars at home and broad used it t
12、o study earthquake, rock - burst , rock failure and in stability and so on, in order to explain and solve in continuous phenomenon of geoscience.Because of complexity of coal and gas delay outburst,the paper will try to study it using Catastrophe Theory.1 Catastrophe Model of Coal and Gas Delay Outb
13、urstSince coal and gas delay outburst is a kind of out.burst,it should also be failure and instability of coal seam falling and gas over flowing caused by kinetic energy which gas internal energy and deformation strain energy of coal mass translate into.The kinds of delay outburst releasing energy h
14、as two like instantaneous outburst,one is elastic stain energy caused by the geost resses acting on coal skeleton, the other is gas internal energ y which is contained by coal mass and pore. So a simplified mechanics model ( Fig.1) is adopted to study delay outburst in the paper. A section is take i
15、n the direction of w orking face (fig. 1(a) ),and the section in the direction of L is simplified to a freely supported beam (fig.1 (b) ) which length is L, vertical width is h,horizontal width is b( Lh, Lb ) , elasticity coeff icient is E,p (t) is geost resses, uniform stress q (t) is the stress sy
16、nthetically reflecting gas internal energy and so on. Because such as geost resses and gas internal energy vary with time when working face is excavated suddenly ,p (t)and q (t) are the functions of time.The ax is flexibility curve of the beam can be expressed as equation (1) using Fourier series.Fig . 1 Th e simplified mechanics model of coal massWith the second series being approx imated,can be denoted as equation(2).
