平面应变状态下岩石剪切带网络数值模拟研究
|
摘要
研究了围压、端面约束、试件高度及界面特性对剪切带网络形成的影响。首先对影响剪切带网络形成的因素(包括试件高度、围压及温度、试件端部轴向应变大小的计算方法的差异)进行了分析。之后采用FLAC 3D对平面剪切带网络进行了数值模拟,其中摩擦角及内聚力为应变软化。探讨了倾向于出现剪切带网络的若干条件。若端面缚束较强且存在一定的侧压力,试件中部出现多重剪切带。若端面缚束较弱,试件端部易于形成剪切带网络,且随试件高度的增加剪切带条数增加。界面法向和切向刚度越大,剪切带穿越断层并按其固有方向延伸能力越强,剪切带网络格局越明显。获得的数值结果可在实验中找到佐证,并且可以用来解释地震中的一些剪切应变局部化现象。
The influences of confining pressure, end constraint, height of specimen and interface on networks of shear bands are investigated numerically. Firstly, some factors including height of specimen, confining pressure, temperature, axial strain and different numerical methods were discussed. Secondly, the FLAC 3D was used to simulate planar multiple shear bands and friction angle and cohesion force were dependent on plastic strain. The conditions, under which the multiple shear bands tend to form, were discussed. As end constraint is strong and confining pressure exists, the multiple shear bands appear in the center of specimen. For weak end constraint, the multiple shear bands form in the end of the rock specimen and numbers of shear bands increases with height of specimen. For large normal and tangential rigidity, shear bands can penetrate old fault and propagate along their inherent directions and the form of networks of shear bands is very apparent. The results obtained agree with many experimental tests and can be used to explain some phenomena of shear strain localization in seism.
The influences of confining pressure, end constraint, height of specimen and interface on networks of shear bands are investigated numerically. Firstly, some factors including height of specimen, confining pressure, temperature, axial strain and different numerical methods were discussed. Secondly, the FLAC 3D was used to simulate planar multiple shear bands and friction angle and cohesion force were dependent on plastic strain. The conditions, under which the multiple shear bands tend to form, were discussed. As end constraint is strong and confining pressure exists, the multiple shear bands appear in the center of specimen. For weak end constraint, the multiple shear bands form in the end of the rock specimen and numbers of shear bands increases with height of specimen. For large normal and tangential rigidity, shear bands can penetrate old fault and propagate along their inherent directions and the form of networks of shear bands is very apparent. The results obtained agree with many experimental tests and can be used to explain some phenomena of shear strain localization in seism.
引文
[1]孙广忠.岩体结构力学[M].北京:科学出版社,1988.
[2]丁国瑜,李永善.我国地震活动与地壳现代破裂网络[J].地质学报,1979,(5):22-34.
[3]LoretB,PrevostJ H.Dynamic strain localization in fluid-saturated porous media[J],Journal ofEngineeringMechanics,ASCE,1991,117(4):907-922.
[4]BesuelleP,DesruesJ,RaynaudS.Experimental characterization of localization phenomenon inside aVosges sandstone in a triaxial cell[J].Int.J.RockMech.Min.Sci.&Geomech.A bstr,2000,37:1223-1237.
[5]王绳祖.岩石的脆性延性转变及塑性流动网络[J].地球物理学进展,1993,8(4):25-37.
[6] deBorstR.Bifurcations in finite element models with a non-associated flow law[J].InternationalJournal forNumerical andAnalyticalMethods inGeomechanics,1998,12:99-116.
[7]EhlersW,VolkW.On theoretical and numerical methods in the theory of porous media based on polar and non-polar elasto-plastic solid materials[J].InternationalJournal ofSolidsStructures,1998,35:4597-4617.
[8]AnandL,GuC.Granular materials: constitutive equations and strain localization[J].Journal of theMechanics andPhysics ofSolids,2000,48:1701-1733.
[9]ShaofanL,WingKamL.Numerical simulation of strain localization in inelastic solids using mesh-free method[J].Int.J.Num.MethodsEngrg,2000,48:1285-1309.
[10]王学滨,潘一山,盛谦等.岩体假三轴压缩及变形局部化剪切带数值模拟[J].岩土力学,2001,22(3):323-326.
[11]王学滨,潘一山,丁秀丽等.孔隙流体对岩体变形局部化的影响及数值模拟研究[J].地质力学学报,2001,7(2):139-143.
[12]王学滨,潘一山,马谨.FLAC3D在岩石变形局部化数值模拟中的应用[J].辽宁工程技术大学学报,2001,20(4):522-523.
[13]I W法默著.岩石的工程性质[M].汪浩译,徐州:中国矿业大学出版社.1987.
[14]ScholzC H.地震与断层力学[M].马胜利等译.北京:地震出版社,1996.
[15]北京大学地震地质教研室等.地震地质学[M].北京:地震出版社,1982.
[16]秦保燕,刘耀炜.线性震中迁移交汇法和强震位置预报机理讨论[J].地震,2000,20(1):17-25.
[17]许绍燮,沈佩文.北京周围地区地震的分布特点与地壳屈曲[J].地震学报,1980,2(2):153-168.
[2]丁国瑜,李永善.我国地震活动与地壳现代破裂网络[J].地质学报,1979,(5):22-34.
[3]LoretB,PrevostJ H.Dynamic strain localization in fluid-saturated porous media[J],Journal ofEngineeringMechanics,ASCE,1991,117(4):907-922.
[4]BesuelleP,DesruesJ,RaynaudS.Experimental characterization of localization phenomenon inside aVosges sandstone in a triaxial cell[J].Int.J.RockMech.Min.Sci.&Geomech.A bstr,2000,37:1223-1237.
[5]王绳祖.岩石的脆性延性转变及塑性流动网络[J].地球物理学进展,1993,8(4):25-37.
[6] deBorstR.Bifurcations in finite element models with a non-associated flow law[J].InternationalJournal forNumerical andAnalyticalMethods inGeomechanics,1998,12:99-116.
[7]EhlersW,VolkW.On theoretical and numerical methods in the theory of porous media based on polar and non-polar elasto-plastic solid materials[J].InternationalJournal ofSolidsStructures,1998,35:4597-4617.
[8]AnandL,GuC.Granular materials: constitutive equations and strain localization[J].Journal of theMechanics andPhysics ofSolids,2000,48:1701-1733.
[9]ShaofanL,WingKamL.Numerical simulation of strain localization in inelastic solids using mesh-free method[J].Int.J.Num.MethodsEngrg,2000,48:1285-1309.
[10]王学滨,潘一山,盛谦等.岩体假三轴压缩及变形局部化剪切带数值模拟[J].岩土力学,2001,22(3):323-326.
[11]王学滨,潘一山,丁秀丽等.孔隙流体对岩体变形局部化的影响及数值模拟研究[J].地质力学学报,2001,7(2):139-143.
[12]王学滨,潘一山,马谨.FLAC3D在岩石变形局部化数值模拟中的应用[J].辽宁工程技术大学学报,2001,20(4):522-523.
[13]I W法默著.岩石的工程性质[M].汪浩译,徐州:中国矿业大学出版社.1987.
[14]ScholzC H.地震与断层力学[M].马胜利等译.北京:地震出版社,1996.
[15]北京大学地震地质教研室等.地震地质学[M].北京:地震出版社,1982.
[16]秦保燕,刘耀炜.线性震中迁移交汇法和强震位置预报机理讨论[J].地震,2000,20(1):17-25.
[17]许绍燮,沈佩文.北京周围地区地震的分布特点与地壳屈曲[J].地震学报,1980,2(2):153-168.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心