Analysis of uplift pressure anomaly of Lijiaxia Dam foundation
Analysis of uplift pressure anomaly of Lijiaxia Dam foundation
复制标题
李家峡坝基扬压异常分析
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
Bao, Teng-Fei
中科院分区：
文献类型：
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作者：
Gu, Chong-Shi;Wu, Zhong-Ru;Bao, Teng-Fei
针对我国李家峡大坝右坝肩出现的抬升异常现象，建立了大坝及坝基渗流三维有限元模型，介绍了防渗帷幕的建模方法，将排水孔模拟为排水子孔，将排水子孔模拟为排水子孔。在此基础上，提出了基于人工神经网络的渗流参数反演方法，并对渗流参数进行了反演，得到了渗流场的渗透张量，为渗流参数的反演提供了一种新的方法。对大坝及坝基渗流进行了三维有限元分析，利用分析结果评价了防渗措施、排水、地质条件等因素对渗流场的影响，并结合钻孔和地基水质测试结果，对隆起异常的原因进行了探讨，结果表明，异常现象是由于浅基础存在灌浆帷幕缺陷和渗漏通道。
With regard to the uplift anomaly phenomenon occurred in the right abutment of Lijiaxia Dam in China,a three-dimensional finite element model for seepage of the dam and its foundation was established.The methods of modeling the seepage prevention curtains were introduced.The drainage holes were modeled as so-called drainage sub-structures.Then an approach of back analysis for seepage parameters based on artificial neural network was proposed.The back analysis was conducted and the permeability tensors of the rock masses were obtained.The three-dimensional finite element analysis of seepage flow through the dam and its foundation was performed.Using the analytic results the influence of various factors such as seepage prevention measures,drainage and geologic conditions in the seepage field was evaluated,and then the cause of uplift anomaly was investigated combined with the results of the drilling and water quality tests in the foundation.It was shown that anomaly phenomenon was due to the grout curtain defects and leakage channel exiting in the shallow foundation.