FLAC数值模拟上机题
计算模型分别如图1、2、3所示,边坡倾角分别为30°、45°、60°,岩土体参数为: 容重r=2500 kg/m3, 弹性模量E=1×108 Pa,泊松比μ=0.3,
抗拉强度σt=0.8×106 Pa,内聚力C=4.2×104 Pa,摩擦角φ=17°
试用FLAC3D软件建立单位厚度的计算模型,并进行网格剖分,参数赋值,设定合理的边界条件,利用FLAC3D软件分别计算不同坡角情况下边坡的稳定性,并进行结果分析。 附 换算公式:
1 kN/m3= 100 kg/m3
剪切弹性模量:G?3D
E
2(1??)体积弹性模量:K?E
3(1?2?)25.36404010060图1 倾角为30°的边坡(单位:m)
30°
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404040100图2 倾角为45°的边坡(单位:m)
60
45°48.45406040100
图3 倾角为60°的边坡(单位:m)
60° 2
48.4540开挖后坡面原始坡面34010060 图4 边坡开挖算例分析 eg.
以45°边坡为例:网格剖分图如下:
60°45°45°
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FLAC3D 2.10Step 28015 Model Perspective20:11:31 Fri Mar 30 2007Center: X: 5.000e+001 Y: 1.000e+000 Z: 3.000e+001Dist: 2.775e+002Rotation: X: 0.000 Y: 0.000 Z: 0.000Mag.: 1Ang.: 22.500Surface Magfac = 0.000e+000Itasca Consulting Group, Inc.Minneapolis, MN USA
实习报告要求:
1、不同坡角边坡位移场和应力场特征; 2、边坡开挖前后位移场和应力场特征; 3、运用强度折减法求解边坡稳定性系数。
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实例分析:
eg.
以45°边坡为例,网格剖分图如下:
FLAC3D 2.10Step 28015 Model Perspective20:11:31 Fri Mar 30 2007Center: X: 5.000e+001 Y: 1.000e+000 Z: 3.000e+001Dist: 2.775e+002Rotation: X: 0.000 Y: 0.000 Z: 0.000Mag.: 1Ang.: 22.500Surface Magfac = 0.000e+000Itasca Consulting Group, Inc.Minneapolis, MN USA 图1 网格剖分图
FLAC3D 2.10Step 28015 Model Perspective20:13:31 Fri Mar 30 2007Center: X: 5.000e+001 Y: 1.000e+000 Z: 3.000e+001Dist: 2.775e+002Rotation: X: 0.000 Y: 0.000 Z: 0.000Mag.: 1Ang.: 22.500Surface Magfac = 0.000e+000Velocity Maximum = 3.837e-004 LinestyleItasca Consulting Group, Inc.Minneapolis, MN USA 图2 速度矢量图
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FLAC3D 2.10Step 28015 Model Perspective20:16:11 Fri Mar 30 2007Center: X: 5.000e+001 Y: 1.000e+000 Z: 3.000e+001Dist: 2.775e+002Rotation: X: 0.000 Y: 0.000 Z: 0.000Mag.: 1Ang.: 22.500Surface Magfac = 0.000e+000Contour of Velocity Mag. Magfac = 0.000e+000 0.0000e+000 to 0.0000e+000 2.5000e-005 to 5.0000e-005 7.5000e-005 to 1.0000e-004 1.2500e-004 to 1.5000e-004 1.7500e-004 to 2.0000e-004 2.2500e-004 to 2.5000e-004 2.7500e-004 to 3.0000e-004 3.2500e-004 to 3.5000e-004 3.7500e-004 to 3.8367e-004 Interval = 2.5e-005Itasca Consulting Group, Inc.Minneapolis, MN USA 图3 速度等值线图
FLAC3D 2.10Step 28015 Model Perspective20:15:20 Fri Mar 30 2007Center: X: 5.000e+001 Y: 1.000e+000 Z: 3.000e+001Dist: 2.775e+002Rotation: X: 0.000 Y: 0.000 Z: 0.000Mag.: 1Ang.: 22.500Surface Magfac = 0.000e+000Contour of Displacement Mag. Magfac = 0.000e+000 0.0000e+000 to 0.0000e+000 0.0000e+000 to 1.0000e-001 1.0000e-001 to 2.0000e-001 2.0000e-001 to 3.0000e-001 3.0000e-001 to 4.0000e-001 4.0000e-001 to 5.0000e-001 5.0000e-001 to 6.0000e-001 6.0000e-001 to 7.0000e-001 7.0000e-001 to 8.0000e-001 8.0000e-001 to 9.0000e-001 9.0000e-001 to 9.6809e-001 Interval = 1.0e-001Itasca Consulting Group, Inc.Minneapolis, MN USA 图4 位移等值线图
最终计算边坡的稳定性系数为:Fs=1.15625
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