地下选厂硐室群开挖引起的围岩破裂特征
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摘要
针对张家湾地下选矿厂硐室群开挖引起的围岩损伤破裂问题,建立RFPA2D数值分析模型,模拟硐室群岩体内部的裂纹起裂、扩展的演化过程,探索阶梯形硐室群开挖卸荷引起的应力效应及其对围岩开裂的影响,并以声发射(AE)作为岩体瞬态卸荷开裂的依据,研究卸荷作用下硐室围岩的破裂范围。结果表明:硐室边墙最先出现起裂破坏,并逐渐沿着竖向发展;围岩裂纹沿着平行于最大主应力的方向发展;岩石非均质性对裂纹的延伸扩展影响很大,均质度越高,应力分布越集中,围岩破裂表现的脆性越强。
Aiming at the damage and fracture problems of surrounding rock mass during the excavation of Zhangjiawan underground mineral processing plant,the evolution rules of cracking initiation and propagation in rock mass are simulated after a RFPA2 Dnumerical analysis model established.And the stress effect induced by unloading condition and its influence on the surrounding rock cracking are explored.The scale of rock mass cracking caused by transient unloading is studied based on the criterion of acoustic emission(AE).The results show that the side wall of chamber first appeared initiation failure,and gradually develop along the vertical direction.The development direction of macro cracks is parallel to the maximum principal stress.And the homogeneity has a great influence on the crack extension and the higher the homogeneity,the more concentrated the stress distribution,the more brittle the fracture of the surrounding rock is.
Aiming at the damage and fracture problems of surrounding rock mass during the excavation of Zhangjiawan underground mineral processing plant,the evolution rules of cracking initiation and propagation in rock mass are simulated after a RFPA2 Dnumerical analysis model established.And the stress effect induced by unloading condition and its influence on the surrounding rock cracking are explored.The scale of rock mass cracking caused by transient unloading is studied based on the criterion of acoustic emission(AE).The results show that the side wall of chamber first appeared initiation failure,and gradually develop along the vertical direction.The development direction of macro cracks is parallel to the maximum principal stress.And the homogeneity has a great influence on the crack extension and the higher the homogeneity,the more concentrated the stress distribution,the more brittle the fracture of the surrounding rock is.
引文
[1]邵安林.矿产资源开发地下采选一体化系统[M].北京:冶金工业出版社,2012.
[2]MARTIN C D,READ R S,MARTIN J B.Observations of brittle failure around a circular test tunnel[J].Int.J.Rock Mech.&Min.Sci.,1997,34(7):1065-1073.
[3]任建喜,葛修润,蒲毅彬,等.岩石卸荷损伤演化机理CT实时分析初探[J].岩石力学与工程学报,2000,19(6):697-697.
[4]李术才,朱维申.复杂应力状态下断续节理岩体断裂损伤机理研究及其应用[J].岩石力学与工程学报,1999,18(2):142-142.
[5]唐春安.岩石声发射规律数值模拟初探[J].岩石力学与工程学报,1997,16(4):268-274.
[6]张春生,侯靖,朱永生,等.深埋隧洞围岩应力分布与破坏机理[J].现代隧道技术,2011,48(3):7-13.
[7]张文举,卢文波,许志宏,等.深埋隧洞开挖引起的围岩开裂研究[J].地下空间与工程学报,2016,12(S2):684-688,719.
[8]周辉,孟凡震,张传庆,等.硬岩应力-应变门槛值特点及产生机制[J].岩石力学与工程学报,2015,34(8):1513-1521.
[9]CAIM,KAISER P K,TASAKAY,et al.Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations[J].International Journal of Rock Mechanics and Mining Sciences,2004,41(5):833-847.
[10]MARTIN C D.Seventeenth Canadian Geotechnical Colloquium:The effect of cohesion loss and stress path on brittle rock strength[J].Canadian Geotechnical Journal,1997,34(5):698-725.
[11]黄润秋,黄达.卸荷条件下岩石变形特征及本构模型研究[J].地球科学进展,2008,23(5):441-447.
[12]李家明,张兆仁,陈强,等.张家湾大型地下硐室群隔墙的稳定性研究[J].现代矿业,2015(5):14-16.
[13]柳小波,陈世金,张坤,等.锚杆间距对大型硐室围岩支护效果的数值模拟研究[J].中国矿业,2015,24(6):94-97.
[14]TANG C A.Numerical simulation of rock failure and associated seismicity[J].Int.J.Rock Mech.Min.Sci.,1997,34:249-262.
[2]MARTIN C D,READ R S,MARTIN J B.Observations of brittle failure around a circular test tunnel[J].Int.J.Rock Mech.&Min.Sci.,1997,34(7):1065-1073.
[3]任建喜,葛修润,蒲毅彬,等.岩石卸荷损伤演化机理CT实时分析初探[J].岩石力学与工程学报,2000,19(6):697-697.
[4]李术才,朱维申.复杂应力状态下断续节理岩体断裂损伤机理研究及其应用[J].岩石力学与工程学报,1999,18(2):142-142.
[5]唐春安.岩石声发射规律数值模拟初探[J].岩石力学与工程学报,1997,16(4):268-274.
[6]张春生,侯靖,朱永生,等.深埋隧洞围岩应力分布与破坏机理[J].现代隧道技术,2011,48(3):7-13.
[7]张文举,卢文波,许志宏,等.深埋隧洞开挖引起的围岩开裂研究[J].地下空间与工程学报,2016,12(S2):684-688,719.
[8]周辉,孟凡震,张传庆,等.硬岩应力-应变门槛值特点及产生机制[J].岩石力学与工程学报,2015,34(8):1513-1521.
[9]CAIM,KAISER P K,TASAKAY,et al.Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations[J].International Journal of Rock Mechanics and Mining Sciences,2004,41(5):833-847.
[10]MARTIN C D.Seventeenth Canadian Geotechnical Colloquium:The effect of cohesion loss and stress path on brittle rock strength[J].Canadian Geotechnical Journal,1997,34(5):698-725.
[11]黄润秋,黄达.卸荷条件下岩石变形特征及本构模型研究[J].地球科学进展,2008,23(5):441-447.
[12]李家明,张兆仁,陈强,等.张家湾大型地下硐室群隔墙的稳定性研究[J].现代矿业,2015(5):14-16.
[13]柳小波,陈世金,张坤,等.锚杆间距对大型硐室围岩支护效果的数值模拟研究[J].中国矿业,2015,24(6):94-97.
[14]TANG C A.Numerical simulation of rock failure and associated seismicity[J].Int.J.Rock Mech.Min.Sci.,1997,34:249-262.