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1.
Construction simulation and real-time control for high arch dam 总被引：1，自引：0，他引：1
A method of combining dynamic simulation with real-time control was proposed to fit the randomness and uncertainty in the
high arch dam construction process. The mathematical logic model of high arch dam construction process was established. By
combining dynamic construction simulation with schedule analysis, the process of construction schedule forecasting and analysis
based on dynamic simulation was studied. The process of real-time schedule control was constructed and some measures for dynamic
adjustment and control of construction schedule were provided. A system developed with the method is utilized in a being constructed
hydroelectric project located at the Yellow River in northwest China, which can make the pouring plan of the dam in the next
stage (a month, quarter or year) to guide the practical construction. The application result shows that the system provides
an effective technical support for the construction and management of the dam.
ZHONG Denghua, born in 1963, male, Dr, Prof.
Supported by National Natural Science Foundation of China(No.50539120), National Basic Research Program of China(“973”Program,No.
2007 CB714101), National Science Fund for Distinguished Young Scholars of China(No.50525927), and National Natural Science
Foundation of China (No.50579045). 相似文献
2.
时间序列分析在水文预报中起重要作用 ,其关键是要建立一个合适的预报模型 .文章提出基于 BP算法的单输出和多输出水文预报时间序列神经网络模型 ,克服了以往多种基于随机分析预报模型的缺点 ,不仅能实现快速灵活的信息处理 ,而且具有很强的非线性映射和自学习、自适应能力 ,这为更精确描述复杂非线性水文过程提供了可能 .通过对历史数据的学习 ,模型可对水文径流量时间序列进行预报 ,两个实例分析表明模型的可行性和有效性 相似文献
3.
提出一种时间序列模型残差诊断捡验的非参数方法．基于残差与时间ｔ的最大相关系数ρ２＊，在零假设Ｈ０∶ρ２＊＝０下，用Ｂｏｏｔｓｔｒａｐ方法建立统计量ρ２＊的零分布。为计算ρ２＊，提出了一种与ＡＣＥ算法相似的ρ算法。有效性分析表明该方法比Ｌｊｕｎｇ－Ｂｏｘ检验更有效。同时还列出一计算机模拟结果和两个实例． 相似文献
4.
An automatic generation method of geological cross-sections in dredging engineering based on 3D geological solid models is presented.The 3D geological models are built applying the non-uniform rational B-splines(NURBS) technique,and a 2D profile can be calculated and generated automatically through Boolean operation to meet the demands of dredging projects.Moreover,an automatic marking method for geological attributes is put forward based on database technology,and the geological attributes include the profile name,scale,horizontal and vertical relative coordinates,geological lithology,and 2D standard lithology legend.At the same time,the automatic marking method can also provide an interactive mode for geological engineers to edit and modify the profile in the modeling system.Practical engineering applications show that the automatic generation method is a simple,flexible,fast and precise visual graphics rendering process that can create 2D standard profiles automatically and efficiently.This method also provides a convenient support tool for geological engineering digital analysis. 相似文献
5.
In most studies of tunnel boring machine(TBM)tunnelling, the groundwater pressure was not considered, or was simplified and exerted on the boundary of lining structure. Meanwhile, the leakage, which mainly occurs in the segment joints, was often ignored in the relevant studies of TBM tunnelling. Additionally, the geological models in these studies were simplified to different extents, and mostly were simplified as homogenous bodies. Considering the deficiencies above, a 3D refined model of the surrounding rock of a tunnel is firstly established using NURBS-TIN-BReP hybrid data structure in this paper. Then the seepage field of the surrounding rock considering the leakage in the segment joints is simulated. Finally, the stability of TBM water diversion tunnel is studied coupled with the seepage simulation, to analyze the stress-strain conditions, the axial force and the bending moment of tunnel segment considering the leakage in the segment joints. The results illustrate that the maximum radial displacement, the minimum principal stress, the maximum principal stress and the axial force of segment lining considering the seepage effect are all larger than those disregarding the seepage effect. 相似文献
6.
A scheme for identifying rolling layers in roller-compacted concrete (RCC) dam automatically was presented. First, a conceptual model was developed. Second, by using a computational geometry method, the auto identification of rolling layers and auto matching between rolling compaction machines and rolling layers were realized based on spatial control points. An application to the construction of Guandi RCC dam showed that the auto identification of rolling layers played an important role in ensuring the engineering quality. 相似文献
7.
认为校企互动不足是影响工程硕士专业学位研究生教育科学发展的瓶颈.介绍天津大学在长期的工程硕士教育实践中的做法,即坚持校企紧密合作,聚焦企业需求,服务行业发展,创新工程硕士教育的办学理念:面向企业自主创新,实施"订单"培养,创新工程硕士生的培养模式;重点服务国家大中型企业和重大工程建设项目,校企合作实现双赢. 相似文献
8.
The loss of life risk evaluation model for dam break is built in this paper.By using an improved Monte Carlo method,the overtopping probability induced by concurrent flood and wind is calculated,and the Latin Hypercube Sampling is used to generate random numbers.The Graham method is used to calculate the loss of life resulting from dam failure.With Dongwushi reservoir located at Hebei Province taken as an example,the overtopping probability induced by concurrent flood and wind is calculated as 4.77×10-6.Loss of life is 24 220 when the warning time is 0.25-1 h and flood severity understanding is vague,which indicates that the risk is intolerable.The losses of life under three other conditions are tolerable:warning time 0.25-1 h,and precise flood severity understanding;warning time more than 1 h,and vague flood severity understanding;warning time more than 1 h,and precise flood severity understanding. 相似文献
9.
Applying stiffness migration method, a 3D finite element mechanical model is established to simulate the excavation and advance processes. By using 3D nonlinear finite element method, the tunnel boring machine (TBM) excavation process is dynamically simulated to analyze the stress and strain field status of surrounding rock and segment. The maximum tensile stress of segment ring caused by tunnel construction mainly lies in arch bottom and presents zonal distribution. The stress increases slightly and limitedly in the course of excavation. The maxi-mum and minimum displacements of segment, manifesting as zonal distribution, distribute in arch bottom and vault respectively. The displacements slightly increase with the advance of TBM and gradually tend to stability. 相似文献
10.
An optimal allocation of earth is of great significance to reduce the project cost and duration in the construction of rock-fill dams. The earth allocation is a dynamic system affected by various time-space constraints. Based on previous studies, a new method of optimizing this dynamic system as a static one is presented. In order to build a generalized and flexible model of the problem, some man-made constraints were investigated in building the mathematic model. Linear programming and simplex method are introduced to solve the optimization problem of earth allocation. A case study in a large-scale rock-fill dam construction project is presented to demonstrate the proposed method and its successful application shows the feasibility and effectiveness of the method. 相似文献