三鑫金铜股份有限公司采区稳定性评价
(广西壮族自治区安全生产监督管理局)
(湖北三鑫金铜股份有限公司)
摘 要
湖北三鑫金铜股份有限公司应用嗣后分段充填采矿方法采矿、深孔落矿工艺。未及时充填的采空区常发生大面积失稳,从而诱发冲击地压,导致地表大面积塌陷。经过对鸡冠咀矿区进行工程地质和地压显现的调查,提出应用声发射技术评价未充填的大规模采空区的稳定性。经过3个多月的长期监测,认为深部水平的431~434采空区尽管有地压活动,但是短期内不会发生大面积失稳。建议尽早充填已采完的空区,避免残留空区的大量积累。
关键词 声发射 空场(空区)处理 地压
Evaluation on Stability of Mining Area in Sanxin Gold-copper Mining Co., Ltd
Li Junping Zhao Wentao
( Safe Production Supervision Administration of Guangxi Zhuang Autonomous Region)
Li Fubao ( Hubei Sanxin Gold-copper Mining Co., Ltd)
Abstract Sublevel stoping with delayed filling and long hole blasting technology is adopted by Hubei Sanxin Gold-copper Mining Co. , Ltd. The large area instability that occurs in untimely filled mined area induces the impact groundpressure which can lead to a large ara ground subsidence. Based on the investigation of the engineering geology and groundpressure apperance in Jiguanzui mining area, it is proposed to use acoustic emission ( AE) technique to evaluate the stabili-ty of large unfilled mined area. According to over three months long term monitoring, it is concluded that though thereis ground pressure activity in No. 431~434 mining areas at deep level, no large area instability will occur in a short peri-od. It is suggested to fill as early as possible the mined area so as to avoid accumulation of large amount of unfilled mined area.
Keywords:Acoustic emission (AE) , Treatment of mined area, Ground pressure
湖北三鑫金铜股份有限公司应用嗣后分段充填采矿方法采矿,深孔落矿工艺。目前的主要开采水平为-270m~-170m。由于地质构造发育,局部岩溶发育,加上近十年的大规模开采及尾砂充填能力的限制,因而井下残留有部分暂未充填的采空区,曾发生过两次冲击地压。例如,1997年12月在016线~017线因-70m采空区的突然失稳,导致其上部溶洞突然塌陷。该冲击地压破坏了-70m分段的开采系统,在地表激起了几丈高的冲击气浪,并形成了约400m2的深10多m的陷落坑。又如,2000年6月017线~018线因-70m南部采空区的突然破坏,也诱发了上部溶洞塌陷。该冲击地压在地表形成了约200m2的类似陷落坑。因此,残留的暂未充填的采空区,严重威胁着采区的整体稳定性及生产安全。
1工程地质概况
鸡冠咀矿区位于扬子准地台下扬子台褶带的西端Ⅵ级构造单元大冶凹褶断束内,处于V级构造单元大冶复式向斜南翼。区内地层发育比较齐全,从元古界至新生界除缺失中、下泥盆统及上侏罗纪外,其余均有出露。本区南部为一系列近东西向的线性褶皱和压性断裂组成,参与褶皱的最新地层为下二叠统大冶群,形成了一系列推挤构造。北部构造线为北西西向,为一系列不连续的背斜、向斜组成,由 于新华夏系构造的影响,局部地段产生北北东向横跨褶皱,北北东、北西西、北东向断裂发育,断裂凹陷而形成“中生代断裂盆地”,沉积了中上三叠统至第四系的较新地层。