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离心机振动台试验中侧向流动地基位移分析方法研究

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世界地震工程 2010年第S1期26卷 225-229页

作者：王睿张建民张嘎清华大学水沙科学与水利水电工程国家重点实验室北京100084 清华大学岩土工程研究所北京100084

通过分析倾斜可液化地基的离心机振动台试验,对离心机振动台试验中地基土体位移分析方法进行了研究,得到了能够有效测量和计算可液化地基地震过程中和震后侧向流动的位移的方法。这种分析方法能够通过对加速度数据的处理和计算,有效地... 详细信息

通过分析倾斜可液化地基的离心机振动台试验,对离心机振动台试验中地基土体位移分析方法进行了研究,得到了能够有效测量和计算可液化地基地震过程中和震后侧向流动的位移的方法。这种分析方法能够通过对加速度数据的处理和计算,有效地克服位移传感器在地震过程中反应不够灵敏导致的位移过程测量的误差,得到合理的地震过程中地基位移变化;同时利用位移传感器对低频位移测量准确的优势,通过量测的震后侧向位移值对计算位移值进行修正,可以得到地震结束后,地基的最终变形。本研究为土工离心机振动台试验中侧向流动地基的位移测量和分析提供可靠有效的方法,也能够为进一步的可液化地基离心模型试验的土体位移相关研究分析提供必要基础。

关键词：离心机振动台可液化地基位移滤波

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非线性剪胀模型土石坝变形计算适用性评价

水力发电学报 2024年第2期43卷 99-109页

作者：王克汤洪洁王睿张建民清华大学水圈科学与水利工程全国重点实验室北京100084 清华大学水利水电工程系北京100084 清华大学水利部水圈科学重点实验室北京100084 水利部水利水电规划设计总院北京100120

以有限元方法为代表的高土石坝变形数值模拟的准确性极大依赖于本构模型对坝料应力应变关系描述的准确性。本文在邓肯-张EB模型基础上,建立了用于分析坝体变形的考虑剪胀的实用性非线性模型(EB-Dilatancy模型,简称为EBD模型)。基于阿尔... 详细信息

以有限元方法为代表的高土石坝变形数值模拟的准确性极大依赖于本构模型对坝料应力应变关系描述的准确性。本文在邓肯-张EB模型基础上,建立了用于分析坝体变形的考虑剪胀的实用性非线性模型(EB-Dilatancy模型,简称为EBD模型)。基于阿尔塔什面板砂砾石坝的大坝变形监测数据,设计了3个反演方案,获得最优的EB模型和EBD模型参数。采用最优参数模拟常规三轴试验,并与实际物理试验进行比较。结果表明:在坝体变形方面,传统的EB模型难以同时准确模拟堆石坝的沉降和水平变形分布,而EBD模型则能够在维持沉降分布模拟精度的基础上提高水平变形的计算精度;EB模型无法实现在合理模拟大坝变形的前提下有效模拟材料单元应力-应变响应,相比之下EBD模型可以同时实现大坝变形和材料单元力学行为的良好模拟。

关键词：高土石坝本构模型剪胀变形监测反演分析三轴试验

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爆炸荷载下隧道口动力离心模型试验研究

世界地震工程 2010年第S1期26卷 212-215页

作者：张应刚马立秋张嘎张建民清华大学岩土工程研究所北京100084 水沙科学与水利水电工程国家重点实验室北京100084 中国核电工程有限公司总图地质所北京100830

城市生命线工程如地铁隧道已经成为恐怖袭击的目标,抗爆防爆问题成为热点研究问题之一。文中采用清华大学50g-t土工离心机进行了爆炸离心模型试验,研究了隧道口区域在爆炸荷载作用下土体-结构物系统的动力响应规律。通过测量和分析土体... 详细信息

城市生命线工程如地铁隧道已经成为恐怖袭击的目标,抗爆防爆问题成为热点研究问题之一。文中采用清华大学50g-t土工离心机进行了爆炸离心模型试验,研究了隧道口区域在爆炸荷载作用下土体-结构物系统的动力响应规律。通过测量和分析土体位移得到了弹坑塑性区的界限,分析结构的应变响应,得出塑性区与结构的相对位置是影响结构响应的主要因素之一。

关键词：隧道爆炸离心模型试验塑性区动力响应

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多次开挖条件下边坡变形的时间效应分析

世界地震工程 2010年第S1期26卷 352-356页

作者：李明张嘎李焯芬张建民清华大学水沙科学与水利水电工程国家重点实验室北京100084

边坡开挖是工程建设中常见的问题。边坡开挖是瞬时卸荷过程,边坡的变形具有复杂的特性。文中进行了边坡开挖的离心模型试验,研究了在不同开挖尺寸下边坡变形的时间效应。试验结果表明:开挖后边坡内没有明显的位移出现的传递过程;竖直方... 详细信息

边坡开挖是工程建设中常见的问题。边坡开挖是瞬时卸荷过程,边坡的变形具有复杂的特性。文中进行了边坡开挖的离心模型试验,研究了在不同开挖尺寸下边坡变形的时间效应。试验结果表明:开挖后边坡内没有明显的位移出现的传递过程;竖直方向上边坡位移最大值出现在边坡中上部。选取坡顶点位移时程曲线进行分析,可以通过时程曲线的发展趋势对边坡的变形和稳定性进行预测。

关键词：边坡开挖变形时间效应

数字流域模型淤地坝模块改进及减水减沙效益评估

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应用基础与工程科学学报 2024年第2期32卷 301-313页

作者：张玍傅旭东孙凯王晨沣清华大学水沙科学与水利水电工程国家重点实验室北京100084

淤地坝具有重要的水土保持作用,但其减水减沙效益的科学评估仍存在困难.一方面,淤地坝减水减沙的物理机制仍难以刻画;另一方面,观测资料有限且难以获取.以概化淤地坝卧管及溢洪道等部分的泄流机制及整体水沙调控机制为基础,改进和检验... 详细信息

淤地坝具有重要的水土保持作用,但其减水减沙效益的科学评估仍存在困难.一方面,淤地坝减水减沙的物理机制仍难以刻画;另一方面,观测资料有限且难以获取.以概化淤地坝卧管及溢洪道等部分的泄流机制及整体水沙调控机制为基础,改进和检验了数字流域模型的淤地坝模块,应用改进后的模型模拟皇甫川流域水沙过程并评估淤地坝减水减沙效益.研究结果表明:不考虑淤地坝的情况下,模型对淤地坝数量较少的近似自然状态期(1979~1986年)适用性较好,而对淤地坝数量较多的受扰状态期(2.07~2.12.)适用性较差,水沙模拟值明显高于实测值.考虑淤地坝的物理机制后,与原模型相比,除个别年份外,改进后的模型对受扰状态期水沙过程的模拟精度具有明显的提高,其逐日流量NSE(Nash-Sutcliffe效率系数)从-51.085~0.450提高到0.134~0.802.逐日输沙率NSE从-56.740~0.390提高到0.066~0.857.使用改进后的模型计算得受扰状态期淤地坝平均拦水量为0.142.10^(8)m^(3),减水效益为40.9%;平均拦沙量为0.050×10^(8)t,减沙效益为50.3%.研究成果可为认识淤地坝调控水沙物理机制提供模型支撑和为淤地坝建设规划提供科学指导.

关键词：淤地坝减水减沙减水减沙效益水土保持数字流域模型分布式水沙模型皇甫川

Three-dimensional seismic response analysis of a concrete-faced rockfill dam on overburden layers

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Frontiers of Structural and Civil engineering 2010年第2期4卷 258-266页

作者： Dakuo FENG ga zhang jianmin {2. state key Laboratory of {2. and engineering Tsinghua UniversityBeijing 100084China

Reasonable seismic response analysis of a high rockfill dam is of great engineering significance in guiding its design and ensuring its seismic safety during operation,especially of a concrete-faced rockfill dam(CFRD)on overburden *** three-dimensional seismic behavior of the Miaojiaba CFRD is simulated and analyzed by the finite element method(FEM).The results indicate that:1)the amplification coefficient along the dam axis gradually increases with the altitude,and reaches maximum at the dam crest;2.the vertical residual deformation mainly exhibits downwards and reaches maximum near the dam crest;3)the earthquake significantly aggravates the deformation of peripheral joints;4)the impounding condition and overburden characteristics have great effects on the dam's seismic response.

关键词： concrete-faced rockfill dam(CFRD) overburden layer dynamic analysis finite element method(FEM)

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苗家坝面板堆石坝材料动力特性试验研究

世界地震工程 2010年第S1期26卷 357-360页

作者：郑瑞华程嵩张建民张嘎清华大学水沙科学与水利水电工程国家重点实验室北京100084

在清华大学2.000 kN大型静/动三轴试验机上进行了苗家坝水电站砼面板堆石坝筑坝材料的大型三轴动力特性试验,包括动剪切模量与阻尼比试验、动残余变形特性试验、动强度试验等。基于试验结果分析了坝料的动力变形规律,为该工程的应力变... 详细信息

在清华大学2.000 kN大型静/动三轴试验机上进行了苗家坝水电站砼面板堆石坝筑坝材料的大型三轴动力特性试验,包括动剪切模量与阻尼比试验、动残余变形特性试验、动强度试验等。基于试验结果分析了坝料的动力变形规律,为该工程的应力变形计算和设计施工提供了试验依据。

关键词：苗家坝大型三轴试验堆石料动力特性动强度

Emerging contaminants:A One Health perspective

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The Innovation 2024年第4期5卷 140-170,139页

作者： Fang Wang Leilei Xiang Kelvin Sze-Yin Leung Martin Elsner Ying zhang Yuming Guo Bo Pan Hongwen Sun Taicheng An Guangguo Ying Bryan WBrooks Deyi Hou Damian EHelbling Jianqiang Sun Hao Qiu Timothy MVogel Wei zhang Yanzheng {2.o Myrna JSimpson Yi Luo Scott XChang Guanyong Su Bryan MWong Tzung-May Fu Dong Zhu Karl JJobst Chengjun Ge Frederic Coulon Jean Damascene Harindintwali Xiankui Zeng Haijun Wang Yuhao Fu Zhong Wei Rainer Lohmann Changer Chen Yang Song Concepcion Sanchez-Cid Yu Wang Ali El-Nag{2.r Yiming Yao Yanran Huang Japhet Cheuk-Fung Law Cheng{2.ng Gu Huizhong Shen Yanpeng {2.o Chao Qin Hao Li Tong zhang Natàlia Corcoll Min Liu Daniel SAlessi Hui Li Kristian KBrandt Yolanda Pico Cheng Gu Jianhua Guo Jianqiang Su Philippe Corvini Mao Ye Teresa Rocha-Santos Huan He Yi Yang Meiping Tong Weina zhang Fidèle Suanon Ferdi Brahushi Zhenyu Wang Syed AHashsham Marko Virta Qingbin Yuan {2.ofei Jiang Louis A.Tremblay Qingwei Bu Jichun Wu Willie Peijnenburg Edward Topp Xinde Cao Xin Jiang Minghui Zheng Taolin zhang Yongming Luo Lizhong Zhu Xiangdong Li DamiàBarceló jianmin Chen Baoshan Xing Wulf Amelung Zongwei Cai Ravi Naidu Qirong Shen Janusz Pawliszyn Yong-guan Zhu Andreas Schaeffer Matthias C.Rillig Fengchang Wu {2.ng Yu James M.Tiedje state key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China university of Chinese Academy of Sciences Beijing 100049China Department of Chemistry Hong Kong Baptist UniversityHong KongChina HKBU Institute of Research and Continuing Education Shenzhen Virtual University ParkShenzhenChina Technical university of Munich TUM School of Natural SciencesInstitute of Hydrochemistry85748 GarchingGermany School of Resources&Environment Northeast Agricultural UniversityHarbin 150030China Climate Air Quality Research UnitSchool of Public Health and Preventive MedicineMonash UniversityMelbourneVICAustralia Faculty of Environmental Science&engineering Kunming University of Science&TechnologyKunming 650500China Ministry of Education key Laboratory of Pollution Processes and Environmental Criteria College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Guangdong key Laboratory of Environmental Catalysis and Health Risk Control School of Environmental Science and EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Ministry of Education key Laboratory of Environmental Theoretical Chemistry South China Normal UniversityGuangzhouGuangdong 510006China Department of Environmental Science Baylor UniversityWacoTXUSA Center for Reservoir and Aquatic Systems Research(CRASR) Baylor UniversityWacoTXUSA School of Environment Tsinghua UniversityBeijing 100084China School of Civil and Environmental engineering Cornell UniversityIthacaNY 14853USA key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province Zhejiang University of TechnologyHangzhou 310014China School of Environmental Science and engineering Shanghai Jiao Tong UniversityShanghai 200240China Laboratoire d’Ecologie Microbienne Universite Claude Bernard Lyon 1UMR CNRS 5557UMR INRAE 1418VetAgro Sup69622 VilleurbanneFrance Department of Pla

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary *** global efforts to mitigate legacy pollutants,the continuous introduction of new substances remains a major threat to both people and the *** response,global initiatives are focusing on risk assessment and regulation of emerging contaminants,as demonstrated by the ongoing efforts to establish the UN’s Intergovernmental Science-Policy Panel on Chemicals,Waste,and Pollution *** review identifies the sources and impacts of emerging contaminants on planetary health,emphasizing the importance of adopting a One Health *** for monitoring and addressing these pollutants are discussed,underscoring the need for robust and socially equitable environmental policies at both regional and international *** actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.

关键词： pollution planet contaminants

Centrifuge model tests on pile-reinforced slopes subjected to drawdown

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Journal of Rock Mechanics and Geotechnical engineering 2020年第6期12卷 1290-1300页

作者： Sujia Liu Fangyue Luo ga zhang state key Laboratory of {2. and engineering Tsinghua UniversityBeijing100084China

Piles are generally an effective way to reduce the risk of slope ***,previous approaches for slope stability analysis did not consider the effect of the piles coupled with the decrease of the water level(drawdown).In this study,a series of centrifuge model tests was performed to understand the deformation and failure characteristics of slopes reinforced with various pile *** the centrifuge model tests,the pile-reinforced slopes exhibited two typical failure modes under drawdown conditions:across-pile failure and through-pile *** the through-pile slope failure,a discontinuous slip surface was observed,implying that the assumption of the slip surface in previous stability analysis methods was *** test results showed that drawdown led to instability of the piles in cohesive soil,as the saturated cohesive soil failed to provide sufficient constraint for *** slope exhibited progressive failure,from top to bottom,during *** deformation of the piles was reduced by increasing the embedment depth and row number of *** addition,the deformation of soils outside the piles was influenced by the piles and showed a similar distribution shape as the piles,and the similarity degree weakened as the distance from the piles *** study also found that the failure mechanism of unreinforced and pile-reinforced slopes induced by drawdown could be described by coupling between the deformation localization and local failure,and it revealed that pile-reinforced slopes could reduce slope deformation localization during drawdown.

关键词： Slope Pile Drawdown Failure Reinforcement Centrifuge model test