关于海州露天矿滑坡灾害的研究
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摘要
海州露天矿投产五十多年以来,由于露天开采和地下开采的相互影响,边帮几乎全部处于采动后的岩移扰动范围内,区域内出现变形、塌陷、地面沉降、地裂缝等各种地质灾害,并且有明显的增大趋势,其中滑坡灾害是发生频率最多、危害最大的一种地质灾害。全面认识海州露天矿发生滑坡的原因、分布及治理措施三方面的内容有助于闭坑后有目的的控制地质灾害的发生。影响海州露天矿发生滑坡的原因有五大因素。一是地质构造因素如断层构造、单斜构造等;二是岩层特性如弱层、节理裂隙等;三是水文地质条件如第四系冲积层松散孔隙水、侏罗系基岩裂隙承压水等;四是人为因素如放炮、行车、不合理的开采活动等;五是煤自燃因素和自然风化因素。将闭坑后按可能发生滑坡的地质背景归纳为不同的地质背景区(危险性分区)不能仅仅根据滑坡发生的原因,而且还要全面了解其危害后果等其它因素综合考虑。其一地质构造和岩性因素,以矿坑北坡为例运用极限平衡理论详细分析了地质构造和岩性因素对滑坡的影响,提出由于9号弱层以上岩体沿弱层顺层蠕变滑移,一定会造成地表拉张沉陷变形,同时边坡出现滑坡的可能性也必然增大,现在稳定系数虽然大于1,但是越来越小,越来越接近于不稳定;其二岩层岩性因素,以北坡E_(24)剖面为例运用有限元法,详细分析了矿坑北坡的安全系数。结论是采场周边只有北帮E_(20)—E_(25)区段边坡岩体沿9~#上弱层滑动,考虑地表裂缝和F_(中1)断层带影响,确定滑坡区为F_(中1)至E_(25)范围内,滑坡区面积为0.24 km~2。采场其余边坡基本稳定;其三气象与地下水因素,结论是滑坡的发生必须有较长时间的前期降水,使地面长期浸泡,达到饱和或过饱和状态,然后遇有短时强降水诱发而形成。北帮边坡坡缓梯级多易于储纳地下水,增加了滑坡发生的几率,南帮相以。其四边坡场地重要性因素,结论是矿坑北面、东面人口集中,建筑物密集,工厂多,发生滑坡后危害比校大,损失比较重,因此危险性强;其五煤自燃及风化因素,通过实地堪察着火点数量,了解了各边坡的风化概况,提出北帮着火点数量最多,受其影响最重。综合分析这五大因素,矿坑闭坑后北一区由于有许多大规模的断层和发达的岩石解理,地质复杂、边坡又多工厂和住宅所以危险性最高,下西区由于强烈的开采活动导致危险性也很高;东坡与南坡是逆层坡,危险性较小,其它各区相对安全,但在强烈的诱发因素条件下也可能触发灾害的发生。滑坡治理的基本思路,第一是建立防灾减灾的理论,做好规划工作。第二是采用工程措施如矿坑外缘建立环坑截水沟,坑底采场内修建蓄水仓,边坡修建帷幕截流、水平放水孔工程、采取支挡、铆固和加固边坡的U型挡墙以及格宾网防护等。第三是是采用预裂爆破、分段装药和空气柱爆破等减震爆破的技术措施;第四是进行监测预报,如围岩监测,人工监控和对异常现象的及时报告等。
Haizhou open-pit mine has put into operation for 50 years,due to the combined effect of open-pit mining and underground mining,while almost all sides are in the scope of rock movement disturbance after post-mining.A large scale of deformation,surface subsidence,ground fissures etc occurred in the pit. There is currently still in the development of deformation and the increasing trend.Landslide is very frequently and is one of the most dangerous geological disasters as well.After careful investigation the causes、distribution and the measures of harness are pointed out in this paper.There are five major factors induced the occurrence of landslide in Haizhou open-pit mine.First, factors such as geological structure;Second,a layer properties,such as weak layer and rock joints and fissures,etc.;Third,hydrogen logical conditions, such as the water from the loose pores of Quaternary alluvium layer,the pressure water of Jurassic bedrock fissure;Fourth,man-made factors such as blasting, traffic,etc;fifth,the spontaneous combustion of coal and natural weathering factors.At first,this article chose the northern slope of the pit as an example,analyzed the impact of geological structure and litho logy on landslide with Limit-Equilibrium Theory,pointed out the rock bedding above the 9th weak layer slips and creeps along the weak Orthorhombic layer,this will of course make stretch,subsidence and deformation happen to the surface.At the same time the possibility of landslides of the slopes are bound to increase.Although the stability coefficient is greater than 1,but is getting smaller and smaller, more close to instability;Then again chose the E24 profile of the northern slope as example,analyzed the safety coefficient of the northern slope of the pit with the Limited-Element method.The conclusion is that only the northern slope around the rock slope of the E_(20)-E_(25) section slides along the #9 weak layers. Considered the cracks in the surface and the impact of the chasm to confirm the landslide area are in the range of E1 to E 25,the landslide area is 0.2 km~2. The other Slopes remain basically stable;thirdly,analyzed relationship between the meteorological factors and groundwater and the impact of the landslide,Pointed out that the occurrence of landslides must have a longer period of time pre-precipitation,so that long-term ground water reaches saturation or over-saturation,and then landslides will be induced by the event of heavy short-term form rainfall.At the same time,according to the shape and angle of the slope analyzed the extent of its impact on the sections of the mine; Fourthly,After analyzing the important factors of slopes in districts, confirmed the areas that are caused more serious harm by event of a landslide; fifthly,through on- the- spot investigation added up the number of ignition points of spontaneous combustion of coal in various districts,found out the weathering of the slope;According to these factors,the paper pointed out that after the mine is shut down,the first northern zone,where,due to the large-scale multi-cleavage complex geological conditions underground and many factories and residences on the ground,exits potential danger;Western zone in the bottom of the pit,as a result of strong mining activities is also highly dangerous;The eastern and the southern slopes are less dangerous because they are inverse slopes,and the other zones are relatively safe.
Haizhou open-pit mine has put into operation for 50 years,due to the combined effect of open-pit mining and underground mining,while almost all sides are in the scope of rock movement disturbance after post-mining.A large scale of deformation,surface subsidence,ground fissures etc occurred in the pit. There is currently still in the development of deformation and the increasing trend.Landslide is very frequently and is one of the most dangerous geological disasters as well.After careful investigation the causes、distribution and the measures of harness are pointed out in this paper.There are five major factors induced the occurrence of landslide in Haizhou open-pit mine.First, factors such as geological structure;Second,a layer properties,such as weak layer and rock joints and fissures,etc.;Third,hydrogen logical conditions, such as the water from the loose pores of Quaternary alluvium layer,the pressure water of Jurassic bedrock fissure;Fourth,man-made factors such as blasting, traffic,etc;fifth,the spontaneous combustion of coal and natural weathering factors.At first,this article chose the northern slope of the pit as an example,analyzed the impact of geological structure and litho logy on landslide with Limit-Equilibrium Theory,pointed out the rock bedding above the 9th weak layer slips and creeps along the weak Orthorhombic layer,this will of course make stretch,subsidence and deformation happen to the surface.At the same time the possibility of landslides of the slopes are bound to increase.Although the stability coefficient is greater than 1,but is getting smaller and smaller, more close to instability;Then again chose the E24 profile of the northern slope as example,analyzed the safety coefficient of the northern slope of the pit with the Limited-Element method.The conclusion is that only the northern slope around the rock slope of the E_(20)-E_(25) section slides along the #9 weak layers. Considered the cracks in the surface and the impact of the chasm to confirm the landslide area are in the range of E1 to E 25,the landslide area is 0.2 km~2. The other Slopes remain basically stable;thirdly,analyzed relationship between the meteorological factors and groundwater and the impact of the landslide,Pointed out that the occurrence of landslides must have a longer period of time pre-precipitation,so that long-term ground water reaches saturation or over-saturation,and then landslides will be induced by the event of heavy short-term form rainfall.At the same time,according to the shape and angle of the slope analyzed the extent of its impact on the sections of the mine; Fourthly,After analyzing the important factors of slopes in districts, confirmed the areas that are caused more serious harm by event of a landslide; fifthly,through on- the- spot investigation added up the number of ignition points of spontaneous combustion of coal in various districts,found out the weathering of the slope;According to these factors,the paper pointed out that after the mine is shut down,the first northern zone,where,due to the large-scale multi-cleavage complex geological conditions underground and many factories and residences on the ground,exits potential danger;Western zone in the bottom of the pit,as a result of strong mining activities is also highly dangerous;The eastern and the southern slopes are less dangerous because they are inverse slopes,and the other zones are relatively safe.
引文
[1]Terzaghi K Mechanism of landslides[J]In.S.Paige(ed) A pplication of Geology to L;ngineering Practice.(;eological Society of A merica,Berkev,1950:83-123.
[2]Skempton 1.W.Residual Strength of clays in landslide,folded strata,and the laboratory),J.Geotechnique,London,1985,35(1):3-18.
[3]TerStepanian,G..Creep of a clay during shear and its rheological model J.Geotechnique,1975,25(2):229-320.
[4]晏同珍,滑坡学,武汉中国地质大学出版社2000.
[5]高根树,张咸恭,大型高速滑坡滑动机理,中国地质灾害与防治学报。1992,3(1):29-32.
[6]工家鼎,强震作用下低角度黄土斜坡滑移的复合机理研究。岩土工程学报.2001,23(4):446-450.
[7]h.J.舒斯特.h.J.克利泽克.铁道部水利学研究院西北研究所译。滑坡分析与防治IMI.北京:中国铁道出版社1987.
[8]王志荣,王念秦,黄土滑坡研究现状综述。中国水土保持,1000-0941(2004)11-0016-03
[9]李皎,陈晋,耿宝军。海州露天矿环境地质灾害演化趋势及对策。辽宁工程技术大学学报,1008-0562(2005)04-0520-04
[10]赵明鹏。阜新地区矿山地质灾害及其防治对策。中国地质灾害与防治学报,1003-8035(2000)04-0064-05
[11]周敏,题正义。大型露天矿闭坑环境问题分析与对策--以辽宁阜新市海州露天矿为例。应用科学,1871-7597(2008)0810098-02
[12]李皎,陈晋,耿宝军。海州露天矿环境地质灾害演化趋势及对策。辽宁工程技术大学学报,1008-0562(2005)04-0520-04
[13]刘玉森,阜新沉陷区受损与治理情况,资源枯竭城市灾害形成机理与控制战略研讨。地质出版社
[14]赵阳升,万志军,康建荣,矿业城市生态环境恶化机理及控制与重建构想。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社,2003.1.8-9
[15]范学理,刘文生,冯国才,矿产资源枯竭城市灾害成因及防治对策。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社33-36
[16]赵明鹏。阜新地区矿山地质灾害及其防治对策。中国地质灾害与防治学报,1003-8035(2000)04-0064-05
[17]严钦尚 曾昭旋 地貌学 高等教育出版社1985.9 1 47
[18]殷智武,徐丁宁。海州露天矿矿山地质灾害成因及主要治理措施探讨。辽宁科技学院学报,1008-3723(2008)03-0037-02
[19]杨天鸿,苗勇勤,唐春安,马新民,霍起元。阜新海洲露天矿顺层边坡变形破坏机理分析。水文地质工程地质,2001(4)36-41
[20]杨天鸿,苗勇勤,唐春安,马新民,霍起元。阜新海洲露天矿顺层边坡变形破坏机理分析。水文地质工程地质,2001(4)36-41
[21]蔡美峰,何满潮,等.岩石力学与工程.北京:科学出版社,2002
[22]张有天,周维垣.岩石高边坡的变形与稳定.北京:中国水利水电出版社,1999.
[23]陈建平,徐文章,煤矸石对矿区环境污染及其影响。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社
[24]田涛,张振文,矿坑煤层自燃机理及防治措施。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社
[25]纪玉石,孙豁然,刘晶辉。露天矿闭坑环境地质灾害危险性分区研究。煤炭学报,2006,31(6)306-309
[26]李正中 王佩贤。露天矿边坡滑(移)动监测与数据处理及滑坡规律性初探。矿山测量,1999(2)23-26
[27]何峰,王来贵,王振伟。海州露天矿滑坡灾害统计分析及信息库建立。地质灾害与环境保,1006-4362(2006)02-0061-03
[28]杨天鸿,苗勇勤,唐春安,马新民,霍起元。阜新海洲露天矿顺层边坡变形破坏机理分析。水文地质工程地质,2001(4)36-41
[29]朝柯,吴昊,白晨曦。海州露天矿气象因素滑坡灾害成因分析及预报。辽宁工程技术大学学报,2008-0562(2006)增刊1-0027-03
[30]冯美生,王来贵,何峰,张红珠。海州露天矿边坡稳定性及变形分析。地质灾害与环境保护,2005,16(12),364-366
[31]于洋,矫兴艳,张大明。海州露天煤矿地质灾害和矿山环境恢复。能源技术与管理,2007(4)56-60
[32]杨占军,夏寿亮,李惠发,肖平。露天矿地质灾害防治的探讨与研究。露天采矿技术,2004(3)8-10
[2]Skempton 1.W.Residual Strength of clays in landslide,folded strata,and the laboratory),J.Geotechnique,London,1985,35(1):3-18.
[3]TerStepanian,G..Creep of a clay during shear and its rheological model J.Geotechnique,1975,25(2):229-320.
[4]晏同珍,滑坡学,武汉中国地质大学出版社2000.
[5]高根树,张咸恭,大型高速滑坡滑动机理,中国地质灾害与防治学报。1992,3(1):29-32.
[6]工家鼎,强震作用下低角度黄土斜坡滑移的复合机理研究。岩土工程学报.2001,23(4):446-450.
[7]h.J.舒斯特.h.J.克利泽克.铁道部水利学研究院西北研究所译。滑坡分析与防治IMI.北京:中国铁道出版社1987.
[8]王志荣,王念秦,黄土滑坡研究现状综述。中国水土保持,1000-0941(2004)11-0016-03
[9]李皎,陈晋,耿宝军。海州露天矿环境地质灾害演化趋势及对策。辽宁工程技术大学学报,1008-0562(2005)04-0520-04
[10]赵明鹏。阜新地区矿山地质灾害及其防治对策。中国地质灾害与防治学报,1003-8035(2000)04-0064-05
[11]周敏,题正义。大型露天矿闭坑环境问题分析与对策--以辽宁阜新市海州露天矿为例。应用科学,1871-7597(2008)0810098-02
[12]李皎,陈晋,耿宝军。海州露天矿环境地质灾害演化趋势及对策。辽宁工程技术大学学报,1008-0562(2005)04-0520-04
[13]刘玉森,阜新沉陷区受损与治理情况,资源枯竭城市灾害形成机理与控制战略研讨。地质出版社
[14]赵阳升,万志军,康建荣,矿业城市生态环境恶化机理及控制与重建构想。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社,2003.1.8-9
[15]范学理,刘文生,冯国才,矿产资源枯竭城市灾害成因及防治对策。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社33-36
[16]赵明鹏。阜新地区矿山地质灾害及其防治对策。中国地质灾害与防治学报,1003-8035(2000)04-0064-05
[17]严钦尚 曾昭旋 地貌学 高等教育出版社1985.9 1 47
[18]殷智武,徐丁宁。海州露天矿矿山地质灾害成因及主要治理措施探讨。辽宁科技学院学报,1008-3723(2008)03-0037-02
[19]杨天鸿,苗勇勤,唐春安,马新民,霍起元。阜新海洲露天矿顺层边坡变形破坏机理分析。水文地质工程地质,2001(4)36-41
[20]杨天鸿,苗勇勤,唐春安,马新民,霍起元。阜新海洲露天矿顺层边坡变形破坏机理分析。水文地质工程地质,2001(4)36-41
[21]蔡美峰,何满潮,等.岩石力学与工程.北京:科学出版社,2002
[22]张有天,周维垣.岩石高边坡的变形与稳定.北京:中国水利水电出版社,1999.
[23]陈建平,徐文章,煤矸石对矿区环境污染及其影响。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社
[24]田涛,张振文,矿坑煤层自燃机理及防治措施。资源枯竭城市灾害形成机理与控制战略研讨。地质出版社
[25]纪玉石,孙豁然,刘晶辉。露天矿闭坑环境地质灾害危险性分区研究。煤炭学报,2006,31(6)306-309
[26]李正中 王佩贤。露天矿边坡滑(移)动监测与数据处理及滑坡规律性初探。矿山测量,1999(2)23-26
[27]何峰,王来贵,王振伟。海州露天矿滑坡灾害统计分析及信息库建立。地质灾害与环境保,1006-4362(2006)02-0061-03
[28]杨天鸿,苗勇勤,唐春安,马新民,霍起元。阜新海洲露天矿顺层边坡变形破坏机理分析。水文地质工程地质,2001(4)36-41
[29]朝柯,吴昊,白晨曦。海州露天矿气象因素滑坡灾害成因分析及预报。辽宁工程技术大学学报,2008-0562(2006)增刊1-0027-03
[30]冯美生,王来贵,何峰,张红珠。海州露天矿边坡稳定性及变形分析。地质灾害与环境保护,2005,16(12),364-366
[31]于洋,矫兴艳,张大明。海州露天煤矿地质灾害和矿山环境恢复。能源技术与管理,2007(4)56-60
[32]杨占军,夏寿亮,李惠发,肖平。露天矿地质灾害防治的探讨与研究。露天采矿技术,2004(3)8-10