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Current developments of research on permafrost engineering and cold region environment:a report of the 8^(th) International Symposium on Permafrost engineering

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Research in cold and Arid Regions 2010年第2期2卷 93-103页

作者： FuJun Niu 1,2,GuoYu Li 1,ShuPing Zhao 1,ShuJuan Zhang 1,YongGuo Zhao 2,HuiJun Jin 1 1.State Key Laboratory of Frozen Soil engineering,cold and Arid Regions Environmental and engineering Research Institute,Chinese Academy of Sciences,Lanzhou,Gansu Province 730000,China 2.Key Laboratory of highway construction and Maintenance Technology for Permafrost Regions of Ministry of communications,cccc First highway consultants co.,ltd.,Xi’an,Shaanxi Province 710068,China Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst State Key Lab Frozen Soil Engn Lanzhou 730000 Gansu Peoples R China cccc First highway consultants co.ltd Permafrost Reg Minist Commun Key Lab Highway Construct & Maintenance Technol Xian 710068 Shaanxi Peoples R China

The Eighth International Symposium on Permafrost engineering was held in Xi’an,China,October *** major topics discussed in the symposium included:permafrost engineering (involving design,construction and evaluation);mitigation of frost hazards in the regions affected by seasonally frozen ground;properties of frozen soils,model development and their applications;frost hazards and periglacial environments in mountain and plateau regions;climatic,environmental and cryospheric changes;and permafrost hydrology,cold regions water resources and land *** papers submitted to the symposium and lectures during the meeting represented some new developments of research on cold region engineering and *** we summarized the works of the symposium in topics including:Permafrost engineering;General geocryology;Properties of frozen soils:model development and their applications;And climatic,environmental and cryospheric *** the symposium,the attendees pointed out that future studies should pay more attention to theoretical study and engineering mechanism study,and also on interaction between climate change and cold region environments and their engineering affects.

关键词： the 8th symposium permafrost engineering cold region environment summarizing

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基于Fick第二定律的非饱和土中汽态水等温扩散研究

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Journal of Central South University 2020年第7期27卷 2017-2031页

作者：刘飞飞毛雪松张建勋吴谦李颖颖许铖 School of highway Chang’an UniversityXi’an 710064China Luoyang Rail Transit Group co. Ltd.Luoyang 471023China

干旱地区非饱和土中汽态水扩散是水分迁移的主要组成部分,这对农业和工程应用具有重要影响。为了揭示非饱和土中汽态水扩散机理,研制了汽态水扩散试验装置,进行了非饱和土汽态水扩散室内试验。试验结果表明非饱和土中汽态水扩散特性符合... 详细信息

干旱地区非饱和土中汽态水扩散是水分迁移的主要组成部分,这对农业和工程应用具有重要影响。为了揭示非饱和土中汽态水扩散机理,研制了汽态水扩散试验装置,进行了非饱和土汽态水扩散室内试验。试验结果表明非饱和土中汽态水扩散特性符合Fick第二定律。基于Fick定律,建立了等温条件下非饱和土汽态水扩散的数学模型,分析了初始含水率梯度、初始含水率分布、土体类型和温度等因素对汽态水扩散系数的影响。结果表明:用所建的数学模型计算的含水率与室内试验结果吻合较好;汽态水扩散系数随着初始含水率梯度和温度的增加而增大;在初始含水率梯度一定的条件下,汽态水系数随着这干土段和湿土段基质吸力比值的增大而增大;含水率和土颗粒粒径均对汽态水扩散系数有所影响,致使土体类型对汽态水扩散系数的影响比较复杂。

关键词：汽态水扩散系数非饱和土数学模型初始含水率梯度初始含水率分布土的类型温度

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港珠澳大桥

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engineering 2019年第1期 25-34页

作者：朱永灵林鸣孟凡超刘晓东林巍 Hong Kong–Zhuhai–Macao Bridge Authority China communications construction co. Ltd. cccc highway consultant co. Ltd.

1.引言港珠澳大桥地处中国东南沿海珠江口,东连香港,西接珠海、澳门,全长55 km,双向六车道、100 km·h–1高速公路标准,设计寿命为120年。大桥的建设改善了珠江口东西两岸交通,加强了粤港澳三地的互联互通和经济融合,促进了"粤港澳大湾... 详细信息

1.引言港珠澳大桥地处中国东南沿海珠江口,东连香港,西接珠海、澳门,全长55 km,双向六车道、100 km·h–1高速公路标准,设计寿命为120年。大桥的建设改善了珠江口东西两岸交通,加强了粤港澳三地的互联互通和经济融合,促进了"粤港澳大湾区"的形成。本文重点介绍港珠澳大桥的设计和建造,特别是人工岛和沉管隧道的新技术。

关键词：沉管隧道人工岛钢圆筒半刚性管节接头港珠澳大桥

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Application of Glass Fiber Reinforced Polymer composite (GFRPC) Escape Pipeline in Tunnel

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Journal of World Architecture 2019年第5期3卷 5-12页

作者： Enhai Tuo The fourth engineering co. Ltd.of CCCC First Highway Engineering Co.Ltd.

During the tunnel construction process,unfavorable geological conditionsare often *** disasters such as collapse,roof fall,water inrush,gas explosion,*** frequently,causing different degrees of property damage and casualties to the construction of the tunnel,seriously affecting harmony during *** domestic emergency hedging is mainly the use of 8-10mm steel coils,but the steel is heavy and not suitable for the frequent movement of *** paper introduces the new Glass Fiber Reinforced Polymer composite(GFRPC)escape pipeline used in Chongqing Jiuyongyi Jinyunshan Tunnel,and compares the traditional steel coil parameters to provide reference for subsequent tunnel hedging measures.

关键词： Tunnel glass fiber reinforced polymer composite escape pipe Light and safety

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Scaled Boundary Methods: Advantages for Elastostatics

Scaled Boundary Methods: Advantages for Elastostatics

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The Sixth World congress on computational Mechanics in conjunction with the second Asian-Pacific congress on computational Mechanics

作者： Andrew J.Deeks School of Civil & Resource engineering The University of Western Australia 35 Stirling highway Crawley WA 6009 Australia

The scaled boundary finite element method, a semi-analytical method of computational mechanics combining advantages of the f'mite element method with advantages of the boundary element method, was originally developed by Wolf and Song for the analysis of dynamic unbounded problems. This paper reviews recent advances in the scaled boundary method and its application to elastostatic problems made by the author and his co-workers. Advances include a virtual work formulation of the method, stress recovery, error estimation and adaptive procedures, direct comparisons of computational efficiency with the finite element method, prescribed displacement procedures, variation of material properties with depth, and meshless and higher order approaches. Applications in geomechanics and fracture mechanics are addressed.

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Hyperspectral Inversion of Heavy Metal content in Reclaimed Soil from a Mining Wasteland Based on Different Spectral Transformation and Modeling Methods

Hyperspectral Inversion of Heavy Metal Content in Reclaimed ...

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中国煤炭学会土地复垦与生态修复专业委员会第七届学术研讨会暨第二届委员会会议

作者： ShiwenZhang QiangShen ChaojiaNie YuanfangHuang JianhuaWang Qingqing Hu XuejiaoDing Yan Zhou YuanpengChen college of Earth and Environmental Science Anhui University of Science and Technology Faculty of Surveying and Mapping Anhui University of Science and Technology college of Resources and Environmental Sciences China Agricultural University No.1 engineering company ltd.of cccc First Harbor engineering company Lrd Soil remediation center of the Ministry of land and resources of China

The heavy metals(Cr,As,Ni,Cd) in soil surface layer(0-20 cm) were measured by chemical method,and the hyperspectral reflectance data were obtained by *** spectral transformation methods,first-order differential(FDR),second-order differential(SDR),continuum removal(CR) and continuous wavelet transform(CWT),are used for the original spectral *** preprocessing effectively eliminated the noise and baseline drifting and also highlighted the locations of the spectral feature *** least squares regression(PLSR) and radial basis function neural network(RBF) were used to study the hyperspectral inversion of four heavy metals(Cr,As,Ni,Cd).The inversion models of four heavy metals were established in the bands with the highest correlation *** inversion effects were comprehensively evaluated by coefficient of determination(R),root mean square error(RMSE) and residual predictive deviation(RPD) *** results showed that the R valuesof the correlation coefficient were significantly improved after smoothing and spectral transformation when compared to the original *** method combined continuous wavelet transform(CWT)with radial basis function neural network(RBF) demonstrated the best inversion effect on the four heavy metals,and when compared to partial least squares regression(PLSR),the RMSE values were reduced by approximately *** CWT-RBF method can be used as a means of inversion of heavy metals in mining wasteland reclaimed land.

关键词： Heavy metals Reclaimed Soil Mining wasteland

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Numerical Study for Stochastic Stability Analysis of Underground Quarry of Oya Tuff in Japan

Numerical Study for Stochastic Stability Analysis of Undergr...

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The Sixth World congress on computational Mechanics in conjunction with the second Asian-Pacific congress on computational MechanicsⅠ

作者： Takafumi Seiki Shingo Matsueda Taiichirou Emori Department of Civil engineering Utsunomiya University 7-1-2 Yoto Utsunomiya City 321-8585 Japan Japan highway Public co. 3-3-2 Kasumigaseki Chiyoda-ku Tokyo City 100-8979 Japan Asanuma co. ltd. 12-6 Higashikouzu-cho Tennoji-ku Osaka City 543-8688 Japan

There are many underground quarries for Oya tuff or the rhyolitic brecciate tuff, in Oya area, Utsunomiya City, Tochighi Prefecture, Japan. It is one of the most famous decorative rock materials for the buildings and the fences in Japan. The plan area of an example quarry has about 20,000m. Recently, the structural stability for these underground quarries should have been considered to redevelop the Oya area. It is one of the main vitalize sightseeing resources as underground space to be active this area again. Almost of them are abandoned quarries. Only some decades of underground quarries have been worked as Oya tuff quarry. It is difficult to decide the mechanical properties of Oya tuff because Oya tuff has the undecided characteristics. Because the main stratum structure randomly includes a lot of clay mineral grains. It is assumed that the undecided randomness follows the normal distribution. To consider the mechanical stability of an underground quarry, the authors are adopted at the linear stochastic finite element method in plane strain state. This stochastic finite element method is based on the asymptotic expansion method. It separates the empirical value into the expectation and the probability value. In this study, the authors assume that the elastic modulus, the cohesion and the internal friction angle of Oya tuff are probability values. It is assumed that the results of numerical analysis make sure the mechanical stability of the underground quarry, roughly. This study will become base information to secure the short term stability of underground quarry just after quarrying

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Statistical Model for Estimating Carbon Dioxide Emissions from a Light-Duty Gasoline Vehicle

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Journal of Environmental Protection 2013年第8期4卷 8-15页

作者： Benjamin Afotey Melanie Sattler Stephen P. Mattingly Victoria C. P. Chen Department of Chemical engineering Kwame Nkrumah University of Science and Technology Kumasi Ghana Department of Civil engineering The University of Texas at Arlington Arlington USA Department of Industrial and Manufacturing Systems engineering The University of Texas at Arlington Arlington USA

The objective of this research was development of a statistical model for estimating vehicle tailpipe emissions of carbon dioxide (co2). Forty hours of second-by-second emissions data (144,000 data points) were collected using an On-Board emissions measurement System (Horiba OBS-1300) installed in a 2007 Dodge Charger car. Data were collected for two roadway types, arterial and highway, around Arlington, Texas, and two different time periods, off peak and peak (both a.m. and p.m.). Multiple linear regression and SAS software were used to build emission models from the data, using predictor variables of velocity, acceleration and an interaction term. The arterial model explained 61% of the variability in the emissions;the highway model explained 27%. The arterial model in particular represents a reasonably good compromise between accuracy and ease of use. The arterial model could be coupled with velocity and acceleration profiles obtained from a micro-scale traffic simulation model, such as coRSIM, or from field data from an instrumented vehicle, to estimate percent emission reductions associated with local changes in traffic system operation or management.

关键词： Carbon Dioxide Model On-Board Emissions Measurement System Mobile Sources

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基于Timoshenko梁及能量变分原理的薄壁箱梁挠度计算分析

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华南理工大学学报（自然科学版） 2018年第4期46卷 51-57,84页

作者：李夏元范伟万水 Yi-lung Mo 沈孔健东南大学交通学院江苏南京210096 中交第二公路勘察设计研究院有限公司湖北武汉430056 Civil and Environmental engineering University of Houstontexasusa77204

基于Timoshenko梁理论和能量变分原理,对单箱单室混凝土薄壁箱梁的翘曲位移函数进行修正,合理构造考虑各翼板翘曲位移函数幅值关系、横截面轴力平衡以及剪切变形影响的翘曲位移函数,建立了体系总势能函数表达式.利用Euler-Lagrange方程... 详细信息

基于Timoshenko梁理论和能量变分原理,对单箱单室混凝土薄壁箱梁的翘曲位移函数进行修正,合理构造考虑各翼板翘曲位移函数幅值关系、横截面轴力平衡以及剪切变形影响的翘曲位移函数,建立了体系总势能函数表达式.利用Euler-Lagrange方程得到了薄壁箱梁剪力滞效应计算理论的微分方程,推导了考虑剪力滞效应影响的简支梁挠度计算公式.结合ABAQUS有限元数值模型算例,对比分析了简支梁在不同荷载工况下挠度沿梁轴向的分布规律.结果表明:针对不同荷载工况下的单箱单室薄壁简支箱梁,文中提出的挠度计算公式的结果与ABAQUS有限元数值吻合较好.同时选取目前工程应用较为广泛的一般梁挠度简化计算方法进行对比分析.由于此类简化计算方法忽略了剪力滞效应存在而产生的附加挠度,导致误差较大,最高达到32.06%,误差范围为21.39%~32.06%.文中所提出的挠度计算方法的结果与有限元数值模拟的结果吻合良好,能较好地反映结构在外荷载作用下的变形规律,且不受加载工况影响,从而验证了文中挠度计算方法的正确性及适用性.

关键词：薄壁箱梁剪力滞效应 Timoshenko梁能量变分原理挠度计算

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