考慮前期降雨的邊坡穩(wěn)定降雨閾值曲面
發(fā)布時間:2018-02-01 01:42
本文關(guān)鍵詞: 降雨閾值 力學模型 非飽和土邊坡 前期降雨 滑坡預警 出處:《巖土力學》2015年S1期 論文類型:期刊論文
【摘要】:在經(jīng)驗性降雨閾值和邊坡穩(wěn)定性數(shù)值分析兩大類研究的基礎(chǔ)上,考慮了降雨入滲和非飽和土性質(zhì),使用巖土有限元軟件Plaxis高級模式對滑坡預警降雨閾值進行研究分析。算例表明,將降雨量在降雨時間范圍內(nèi)分成2段后,得到的邊坡穩(wěn)定性變化與實際情況更接近,重新定義前期降雨為在給定初始條件下引起邊坡最危險滑裂面到坡面之間土體吸力分布發(fā)生變化的降雨。前期降雨時長與潛在滑裂面最大深度成正比,與飽和滲透系數(shù)成反比。將前期降雨量引入到降雨強度—持時曲線中作為第三個空間坐標軸,將該曲線拓展為前期降雨量-降雨強度-持時曲面。通過一基巖型邊坡算例展示了閾值曲面的建立方法,并通過與模型試驗數(shù)據(jù)的對比驗證了其可靠性。
[Abstract]:Based on empirical rainfall threshold and slope stability numerical analysis, rainfall infiltration and unsaturated soil properties are considered. Using the Plaxis advanced model of geotechnical finite element software, the rainfall threshold of landslide early warning is studied and analyzed. The example shows that the rainfall is divided into two sections in the rainfall time range. The obtained slope stability change is closer to the actual situation. Redefine the pre-rainfall as the rainfall that causes the change of soil suction distribution between the most dangerous slip surface and slope surface under the given initial conditions. The duration of the early rainfall is proportional to the maximum depth of the potential slip surface. It is inversely proportional to the saturation permeability coefficient. The rainfall of the previous period is introduced into the rainfall intensity-duration curve as the third spatial coordinate axis. The curve is extended to a surface of rainfall, rainfall intensity and duration of time. A calculation example of bedrock slope shows the method of establishing threshold surface, and the reliability of the curve is verified by comparison with model test data.
【作者單位】: 清華大學土木工程安全與耐久教育部重點實驗室;
【基金】:國家重點基礎(chǔ)研究發(fā)展計劃(No.2014CB047004)
【分類號】:TU43
【正文快照】: 1引言降雨是誘發(fā)滑坡災害的主要因素之一,其對邊坡穩(wěn)定性的影響成為近些年來學者關(guān)注的熱點話題。目前在這方面的研究主要分為兩類,一類是根據(jù)歷史上誘發(fā)滑坡的降雨數(shù)據(jù)建立經(jīng)驗性降雨閾值,作為滑坡預警的依據(jù);另一類是通過試驗方法或數(shù)值方法研究降雨對邊坡穩(wěn)定性的影響規(guī)律,
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相關(guān)期刊論文 前1條
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【共引文獻】
相關(guān)期刊論文 前10條
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