水位变动易引起边坡破坏,造成巨大损失。合理评价水位变动条件下边坡安全性需要阐明其破坏机理,为此进行了水位变动条件下土坡离心模型试验。试验结果表明,水位变动首先在坡体中下部引起局部破坏,该局部滑裂面向上发展至坡顶形成了完整滑裂面。土坡破坏不是瞬时发生的,水位变动过程引起的变形局部化累积是土坡发生破坏的本质原因。水位变动导致土坡变形局部化程度单调增加,此外局部破坏在其附近引起新的变形局部化并在坡体内扩展。水位变动条件下土坡表现出变形局部化累积与破坏过程的显著耦合特性,这是土坡破坏分析方法需要合理反映的。
Abstract
Water level fluctuation has induced a large number of slope failures, resulting in huge losses of life and property. Clarifying the failure mechanism is a requisite for a reasonable evaluation on slope safety under water level fluctuation condition. Such mechanism was investigated using centrifuge model tests in the present research. Test results demonstrate that water level fluctuation gave rise to local failure in the mid-lower part of the slope which developed upwards until the final slip surface was formed. The accumulation of local deformation, instead of instantaneous destruction, is the fundamental cause of slope failure under water level fluctuation. The local deformation developed monotonically and further triggered new local deformations around and extended in the slope. In summary, the extinct coupling of local deformation accumulation and failure process under water level fluctuation should be well considered in the analysis of slope failure.
关键词
土坡 /
局部变形 /
水位变动 /
离心模型试验 /
破坏机理
Key words
soil slope /
local deformation /
water level variation /
centrifuge model test /
failure mechanism
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参考文献
[1] 唐志政, 汪 洋, 吴 晔. 库水位波动条件下万州瓦窑坪滑坡稳定性分析[J]. 水文地质工程地质, 2015, 42(1): 129-133.
[2] 罗方悦, 张 嘎. 水库区均质边坡安全可靠度简化实用分析方法[J]. 长江科学院院报, 2017, 34(7): 106-110.
[3] 王明华, 晏鄂川. 水库蓄水对库岸滑坡的影响研究[J]. 岩土力学, 2007, 28(12): 2722-2725.
[4] 汪 斌,唐辉明,朱杰兵,等. 考虑流固耦合作用的库岸滑坡变形失稳机制[J]. 岩石力学与工程学报,2007,26(增刊2):4484-4489.
[5] 唐晓松, 郑颖人, 唐辉明, 等. 水库滑坡变形特征和预测预报的数值研究[J]. 岩土工程学报, 2013, 35(5): 940-947.
[6] TAKASHI H, SHINICHIRO T, ATSUSHI Y, et al. Independent Reinforced Soil Structure with Pile Foundation-Piled Geo-wall: An Experimental Study on the Application to Seismic Measure for Embankment[J]. Soils and Foundations, 2010, 50(5): 565-571.
[7] VISWANADHAM B V S, RAJESH S. Centrifuge Model Tests on Clay Based Engineered Barriers Subjected to Differential Settlements[J]. Applied Clay Science, 2009, 42(3/4): 460-472.
[8] ZORNBERG J G, SITAR N, MITCHELL J K. Performance of Geosynthetic Reinforced Slopes at Failure[J]. Journal Geotechnical and Geoenvironmental Engineering, 1998, 124(8): 670-683.
[9] WANG Rui, ZHANG Ga, ZHANG Jian-min. Centrifuge Modelling of Clay Slope with Montmorillonite Weak Layer under Rainfall Condition[J]. Applied Clay Science, 2010, 50(3): 386-394.
[10]杨春宝, 朱 斌, 孔令刚, 等. 水位变化诱发粉土边坡失稳离心模型试验[J]. 岩土工程学报, 2013, 35(7): 1261-1271.
[11]ZHANG Ga, HU Yun, ZHANG Jian-min. New Image Analysis-based Displacement-measurement System for Geotechnical Centrifuge Modeling Tests[J]. Measurement, 2009, 42(1): 87-96.
[12]ZHANG Ga, WANG Li-ping. Integrated Analysis of a Coupled Mechanism for the Failure Processes of Pile-reinforced Slopes[J]. Acta Geotechnica, DOI: 10.1007/s11440-015-0410-z.
基金
国家重点研发计划课题项目(2018YFC1508503);国家自然科学基金项目(51479096)
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