| 裂隙黄土边坡三维稳定性极限分析 |
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| 引用本文： | 朱学亮,邵生俊,沈晓钧,邵帅,刘小康.裂隙黄土边坡三维稳定性极限分析[J].岩土力学,2022,43(10):2735-2743. |
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| 作者姓名： | 朱学亮 邵生俊 沈晓钧 邵帅 刘小康 |
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| 作者单位： | 1. 西安理工大学 岩土工程研究所 陕西 西安 710048；2. 西安理工大学 陕西省黄土力学与工程重点实验室，陕西 西安 710048；
3. 陕西省引汉济渭工程建设有限公司，陕西 西安 710000；4. 西安理工大学 建筑与城市规划系，陕西 西安 710048 |
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| 基金项目： | 国家自然科学基金（No. 52108342）；陕西省自然科学基础研究计划-引汉济渭联合基金项目（No. 2019JLP-21，No. 2019JLZ-13）；西安理工大学博士启动金（No. 107-451122001）；陕西省水利科技计划项目（No. 2021slkj-12）。 |
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| 摘 要： | 黄土边坡中竖直裂隙的发育往往会对边坡稳定产生影响。相对于平面应变机制，建立三维破坏机制下边坡稳定性分析方法更能接近实际边坡失稳情况。基于塑性极限分析上限法，考虑预先存在竖直裂隙的三维黄土边坡不同破坏机制（坡面破坏、坡脚破坏和坡底破坏），建立能量平衡方程及其无量纲临界高度值γH/c表达式，采用随机搜索法得到了临界高度的上限解。分析了约束宽度、边坡坡度、内摩擦角以及裂隙深度对三维竖直裂隙黄土边坡临界高度值的影响。结果表明：对于坡脚破坏机制，临界高度值随着裂隙深度的增加而减小，减小至临界裂隙深度 (δ /H)min后，裂隙深度的增加不再影响临界高度值；临界裂隙深度随着坡度β 的增大而增大，随着内摩擦角φ 的增大而减小。当约束宽度B/H<0.8时，大多数破坏机制为坡面破坏。当约束宽度B/H=0.8、内摩擦角φ =10° 及约束宽度B/H=0.6、内摩擦角φ =15° 时，边坡的破坏从坡面破坏机制逐渐过渡到坡脚破坏机制。存在竖直裂隙的黄土边坡比完整边坡具有更小的临界高度，约束宽度及内摩擦角会对三维黄土边坡破坏机制产生影响。
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| 关 键 词： | 边坡失稳 竖直裂隙 破坏机制 上限法 |
| 收稿时间： | 2021-12-09 |
| 修稿时间： | 2022-06-22 |
Three-dimensional stability limit analysis of cracked loess slopes |
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| ZHU Xue-liang,SHAO Sheng-jun,SHEN Xiao-jun,SHAO Shuai,LIU Xiao-kang.Three-dimensional stability limit analysis of cracked loess slopes[J].Rock and Soil Mechanics,2022,43(10):2735-2743. |
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| Authors: | ZHU Xue-liang SHAO Sheng-jun SHEN Xiao-jun SHAO Shuai LIU Xiao-kang |
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| Institution: | 1. Institute of Geotechnical Engineering, Xi’an University of Technology, Xi’an, Shaanxi 710048, China; 2. Shaanxi Key Laboratory of Loess Mechanics and Engineering, Xi’an University of Technology, Xi’an, Shaanxi 710048, China; 3. Hanjiang to Weihe River Valley Water Diversion Project Construction Co., Ltd., Xi’an, Shaanxi 710000, China; 4. Department of Architecture and Urban Planning, Xi’an University of Technology, Xi’an, Shaanxi 710048, China |
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| Abstract: | The
development of vertical cracks in loess slopes often affects slope stability.
Compared with the plane strain mechanism, the slope stability analysis under
the three-dimensional (3D) failure mechanism is closer to the actual slope
instability. Based on the upper bound method of plastic limit analysis,
different failure mechanisms (face failure, toe failure and base failure) of 3D
loess slope with pre-existing cracks are considered, the energy balance
equation and its dimensionless critical height expression γH/c are established, and
the upper bound solution of critical height is obtained by random search
method. The effects of constraint width, slope angle, internal friction angle
and crack depth on the critical height of 3D vertical cracked loess slopes are
analyzed. The results indicate that for the toe failure mechanism, the critical
height decreases with the increase of crack depth, and the increase in crack
depth no longer affects the critical height after reducing to the critical
crack depth (δ /H)min. The critical crack depth increases with the increase
of slope angle β and decreases with
the increase of internal friction angle φ.
When the constraint width B/H<0.8, most of the failure mechanism is of face failure.
When the constraint widthB/H=0.8 , internal friction angle φ =10°, and the constraint width B/H=0.6, internal friction angle φ =15°, the failure mechanism of the slope gradually transits from
the face failure mechanism to the toe failure mechanism. The loess slope with
vertical cracks has a smaller critical height than the intact slope. The
constraint width and internal friction angle can affect the failure mechanism
of 3D loess slopes. |
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| Keywords: | slope instability vertical cracks failure mechanism upper bound method |
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