混凝土坝浇筑块长度三维仿真敏感分析

：本文采用全过程仿真粘弹性空间有限单元法,对混凝土坝浇筑块长度进行了敏感分析,共计算了7个浇筑块长度,计算结果表明浇筑块长度愈大强约束区浇筑块中心的最大主拉应力愈小,这一有关浇筑块长度的新概念从力学计算上支持了混凝土坝通仓浇筑。     

混凝土大坝浇筑安排计算机仿真求解

在混凝土大坝浇筑过程中，合理安排坝快浇筑顺序十分重要。在对经问题分析的基础上，按照动态规划最优化原理，结合工程施工的要求，提出几个优先原则作为决策的标准，通过计算机仿真模型模仿实际系统的运行状态及随时间变化过程，估计和推断实际系统的真实参数和真实性能。采用不同的原则进行计算，找到在一定条件下的相对化的浇筑顺序，给出一种解决方法。     

碾压混凝土坝浇筑进度三维仿真

随着虚拟现实技术的发展,三维仿真作为一种全新角度的管理方法和技术手段在工程进度管理中起到越来越重要的作用。本文讨论了基于OSG图形引擎和QT应用程序开发框架的大坝浇筑仿真系统的开发方法。该系统并可根据施工的高程数据来生成相应的浇筑情况。基于上述方法设计实现了一个碾压混凝土坝浇筑过程三维仿真系统。     

龙滩碾压混凝土坝的仿真计算

本文是在作者的研究成果“龙滩碾压混凝土坝的温控研究”和“模拟碾压混凝土坝成层浇筑过程温度场的解析解的基础上对龙滩碾压混凝土坝夏季开工坝段进行仿真计算。研究结果表明，当开工日期在夏季时，基础混凝土热量倒灌现象严重，最高温升和最大水平正应力 发生在靠近基础的常压混凝土浇筑层中。因此，夏季开工坝段的温控重点是基础常压混凝土垫层。坝体温度降低到稳定场需要一个很大的时间过程，对于龙滩碾压混凝土坝，大约需要４     

浅谈混凝土坝施工中混凝土的浇筑与养护

为了避免由于不均匀沉降引起坝体开裂，常用结构缝将坝体分段；为了控温防裂和施工方便，用纵缝将坝段分成若干柱状段，形成浇筑块。     

混凝土坝仿真应力分析方法

混凝土坝是逐层浇筑的，施工过程对坝体温度场和应力场有重要影响。模拟施工过程进行仿真计算是困难的。为了真实地模拟施工过程并保证较高的计算精度，需要庞大的存储量和很长的机时，限于目前的计算机上即可完成混凝土高坝的仿真计算。     

铜街子碾压混凝土坝连续浇筑高块的施工经验

为取得碾压混凝土坝快速施工的经验,在铜街子工程进行了连续上升至16m高度的尝试。本文指出高块连续浇筑要具备一定的施工条件才能实现,除拌和系统生产能力外,在现场实施混凝土运输,入仓路线和方法是关键;其次要核算通仓浇筑带来的温度应力问题并采取相应的对策。本文还介绍了为了解高块连续浇筑的温度及温度应力问题所布置的仪器和观测成果。     

混凝土坝温控因素敏感分析及其在多维空间的凝聚方程

采用全过程仿真粘弹性空间有限单元法，对9种温控因素进行了敏感分析，得出温控因素变化浇筑块强约束区中心最高温度、最大基础温差和最大拉应力的影响。在敏感分析的基础上，采用回归分析和拉格郎日插值方法在温控因素多维空间建立了凝聚方程，利用凝聚方程可计算任意施工条件下的最大基础温差和最大拉应力。     

THREE-DIMENSIONAL NUMERICAL SIMULATION OF BOD-DO FOR LARGE RESERVOIR

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｃａｕｓｅｔｈｅｒｅａｒｅｍａｎｙｂｕｉｌｔａｎｄｂｕｉｌｄｉｎｇｌａｒｇｅｄｅｅｐｒｅｓｅｒｖｏｉｒｓｉｎＣｈｉｎａ ,ｔｈｅｓｔｕｄｙｏｆｔｈｅｍｏｄｅｌｏｆＢｉ ｏｌｏｇｉｃａｌＯｘｙｇｅｎＤｅｍａｎｄ (ＢＯＤ)ａｎｄＤ     

THREE-DIMENSIONAL TURBULENCE NUMERICAL SIMULATION OF A STEPPED SPILLWAY OVERFLOW

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅａｐｐｌｉｃａｔｉｏｎｏｆｔｈｅｓｔｅｐｐｅｄｓｐｉｌｌｗａｙｈａｓｈａｄａｌｏｎｇｈｉｓｔｏｒｙ .Ｔｈｅ ｐｈｙｓｉｃａｌｍｏｄｅｌｔｅｓｔｓｔｕｄｙｏｆｔｈｅｓｔｅｐｐｅｄｓｐｉｌｌｗａｙｈａｓｂｅｅｎ ｐｅｒｆｏｒｍ     

THREE-DIMENSIONAL TURBULENCE NUMERICAL SIMULATION OF A STEPPED SPILLWAY OVERFLOW

In this paper, the κ-ε two-equation turbulence model was used to simulate the three-dimensional turbulent flow of the stepped spillway at the Yubeishan reservoir. In order to solve the curved free water surface and to handle the complex boundary conditions, the fractional Volume Of Fluid (VOF) model that is applicable to the solution of the stratified two-phase flow was intorduced to the κ-ε turbulence model and the unstructured grid was used for the discretization of the irregular simulation domain. By these methods, the turbulent flow field of the stepped spillway was simulated successfully.The location of the free surface along the spillway, the magnitude and distribution of the velocity, the pressure distribution on the step surface, the turbulence kinetic energy and turbulence dissipation rate were obtained by simulation. The changes and distributions of these characteristics along the width of the spillway were also obtained. The energy dissipation ratio of the stepped spillway was calculated according to the upstream and downstream water depth and velocities.     

THREE-DIMENSIONAL NUMERICAL SIMULATION OF INTAKE MODEL WITH CROSS FLOW

The hydrodynamics of a pump sump consisting of a main channel,pump sump,and intake pipe is examined using Truchas,a three-dimensional Navier-Stokes solver,with a Large Eddy Simulation(LES) turbulence model.The numerical results of streamwise velocity profiles and flow patterns are discussed and compared with experimental data of Ansar and Nakato.Fairly good agreement is obtained.Furthermore,unlike Ansar et al.'s inviscid solution,the proposed numerical model includes the effect of fluid viscosity and consid...     

THREE-DIMENSIONAL NUMERICAL SIMULATION OF WIND-INDUCED CIRCULATION IN LAKE TAIHU

1 .　INTRODUCTIONHydrodynamicshassignificanteffectsoneutroph icationinshallowlakesbecausewavesandcurrentscanleadtosedimentresuspensionresultinginnutrientre lease,highturbidityandre distributionofnutrientsandSuspendedParticulateMatter (SPM ) .Asare sult ,therecoveryofthelimnicecosystemismorethanlikelytobepreventedespeciallyinshallowlakes[1 3] ,whichiswhyhydrodynamicsandsedimentdynamicshavereceivedgreatattentioninthelakeecosystemre searchandothershallowwaterareas[4 8] .Asthethirdlargestf…     

THREE-DIMENSIONAL NUMERICAL SIMULATION OF WAVE SLAMMING ON AN OPEN STRUCTURE

The three-dimensional numerical simulation of wave slamming on an open structure in the splash zone is carried out based upon the Volume Of Fluid (VOF) method.A wave basin is established by solving the...     

混凝土受压性能的均质细观数值模拟

将混凝土看作由骨料、砂浆及它们之间的界面组成的三相复合材料，在细观层次上建立了均质混凝土棱柱体试件的随机骨料模型，分别赋予细观单元弹脆性和弹塑性本构关系，研究了采用不同本构关系的混凝土棱柱体试件在单轴压缩荷载作用下的细观损伤演化过程，分析了宏观应力应变曲线的差异，并将计算结果与试验结果做了比较。结果表明：混凝土试件的破坏是由于细观损伤的积累导致的；界面相是混凝土材料内部最薄弱的地方；砂浆单元采用弹塑性本构关系时所得混凝土棱柱体受压的宏观应力－应变全曲线与试验结果吻合较好。     

NUMERICAL SIMULATION OF THREE-DIMENSIONAL VORTEX DYNAMICS IN WAKE OF A CIRCULAR CYLINDER

The studies concerning the wake transition regime of the flow around a circular cylinder have drawn much attention in these years. Many experiments have been conducted for this problem but no accurate three-dimensional numerical simulations have hitherto been made. In this paper, a parallel procedure was developed to solve the three-dimensional Navier-Stokes equations on an SGI Origin3900 machine. Two different parallel strategies on this application were analyzed about their efficiency. It is found that the critical Reynolds number is 195, and the wake flow below this Reynolds number is purely two dimensional one, while the Reynolds number goes beyond this critical point, the wake flow becomes unstable under three-dimensional small disturbances. The transition regime involves two modes of small-scale three-dimensional instability (modes A and B), depending on the regime of Reynolds number ( Re ). It is also found that the two different modes A and B exhibit different physical features of the flow. And many other important questions were addressed in this paper.     

用分布式光纤测温系统测量混凝土面板坝渗流的建议

简述了分布式光纤温度传感测量系统的基本原理和将其应用于混凝土面板坝渗流测量的两种方法，详述了电热脉冲法进行渗流检测的布置和施工工艺，详细讨论并分析了电热脉冲法进行渗流测量存在的疑问和主要问题，并提出了解决方法。     

CALCULATION OF VISCOUS FLOW AROUND CIRCULAR CYLINDER WITH THREE-DIMENSIONAL NUMERICAL SIMULATION

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｆｌｏｗａｒｏｕｎｄａｃｉｒｃｕｌａｒｃｙｌｉｎｄｅｒｉｓｖａｌｕａｂｌｅｉｎｏｉｌｃｏｍｐａｎｉｅｓｏｒｏｆｆｓｈｏｒｅｉｎｄｕｓｔｒｙｔｈａｔｒｅｌｙｉｎｍｏｓｔｃａｓｅｓｏｎｓｕｂｓｅａｐｉｐｅｌｉｎｅｏｒｒｉｓｅｒｓｔｏｔｒａｎｓｐｏｒｔｇａｓａｎｄｏｉｌｆｒｏｍｏｃｅａｎｇｒｏｕｎｄｓｔｏｌａｎｄｏｒｓｕｒｆａｃｅｐｌａｔｆｏｒｍ .Ｗｅｓｈｏｕｌｄｅｎｓｕｒｅｔｈａｔｔｈｅｓｅｏｆｆｓｈｏｒｅｓｔｒｕｃｔｕｒｅｓａｒｅｒｅｓｉｓ ｔａｎｔａｎｄｓｔａｂ…