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水电能源科学 2010年第5期28卷 59-61页

作者：郑付刚庄培源游强强河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对处理监测数据时因缺少坝体实测温度而在回归分析时采用温度谐波因子的问题,阐述了温度谐波因子在回归分析中的原理后对其进行了改进,并考虑了不同气温年变幅的影响。实例结果表明,改进后的方法使计算精度有所提高,且更符合大坝实际... 详细信息

针对处理监测数据时因缺少坝体实测温度而在回归分析时采用温度谐波因子的问题,阐述了温度谐波因子在回归分析中的原理后对其进行了改进,并考虑了不同气温年变幅的影响。实例结果表明,改进后的方法使计算精度有所提高,且更符合大坝实际工作机制。

关键词：大坝监测温度谐波因子回归分析年变幅

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施工期混凝土拱坝温度监测资料分析

水电能源科学 2010年第1期28卷 67-69,34页

作者：陶丛丛王校利冯宇强徐波河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

为分析施工期混凝土拱坝的温度场性态、防止温度裂缝,提出一种施工期混凝土拱坝温度监测资料分析法,并以某混凝土拱坝为例,介绍了温度计的布置及温控措施,分析了温差与温度计测值变化规律。根据温度计测值绘制了典型坝段的温度计等值线... 详细信息

为分析施工期混凝土拱坝的温度场性态、防止温度裂缝,提出一种施工期混凝土拱坝温度监测资料分析法,并以某混凝土拱坝为例,介绍了温度计的布置及温控措施,分析了温差与温度计测值变化规律。根据温度计测值绘制了典型坝段的温度计等值线,并分析了温度场分布。结果表明,温度计布置合理,采取的温控措施行之有效,可供借鉴。

关键词：施工期混凝土拱坝温度资料分析

RBF神经网络在坝肩断(夹)层位移监测中的应用

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水电能源科学 2010年第3期28卷 60-62页

作者：佟剑杰钱飞张磊崔永建河海大学水利水电学院江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对RBF神经网络可解决BP算法收敛速度慢、易陷于局部最小等问题,介绍了RBF下神经网络的训练与设计方法,构建了某坝坝肩断(夹)层位移数据分析的RBF神经网络,并对测试样本进行了预测。结果表明,采用该法的预测误差约为±0.2 mm,预测效果... 详细信息

针对RBF神经网络可解决BP算法收敛速度慢、易陷于局部最小等问题,介绍了RBF下神经网络的训练与设计方法,构建了某坝坝肩断(夹)层位移数据分析的RBF神经网络,并对测试样本进行了预测。结果表明,采用该法的预测误差约为±0.2 mm,预测效果较好。

关键词：断(夹)层 RBF网络 Matlab newrb函数位移监测

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李家峡拱坝水平位移变化规律异常成因分析

水电能源科学 2010年第7期28卷 60-63,174页

作者：彭妍娄一青虞鸿汪亚超河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 温州市水利局浙江温州325000

针对李家峡大坝垂线监测资料分析中发现的异常现象,对其进行物理成因分析,建立位移统计模型分析了其主要影响因素,并通过对李家峡大坝的大量模拟研究建立了三维有限元模型,在多模型、多工况、多种材料参数组合计算的基础上,分析了大坝... 详细信息

针对李家峡大坝垂线监测资料分析中发现的异常现象,对其进行物理成因分析,建立位移统计模型分析了其主要影响因素,并通过对李家峡大坝的大量模拟研究建立了三维有限元模型,在多模型、多工况、多种材料参数组合计算的基础上,分析了大坝变形异常成因,查清了水平位移变化规律异常的原因。

关键词：李家峡拱坝水平位移变化规律物理成因分析 Arch Dam 三维有限元模型主要影响因素监测资料分析大坝变形异常现象异常成因模型分析模拟研究多种材料参数组合多模型多工况统计计算

基于HyperMesh软件的复杂结构有限元建模

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水电能源科学 2010年第8期28卷 100-102,105页

作者：彭妍娄一青汪亚超徐宝松河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 温州市水利局浙江温州325000

针对结构复杂的大坝有限元结构分析中常需在已有HyperMesh格式有限元模型上增加某些附属混凝土结构,以李家峡双曲拱坝为例,采用HyperMesh软件中的Geom和Tool等子面板建立新增附属结构的几何模型,并剖分为三维有限元模型,进而与AutoCAD... 详细信息

针对结构复杂的大坝有限元结构分析中常需在已有HyperMesh格式有限元模型上增加某些附属混凝土结构,以李家峡双曲拱坝为例,采用HyperMesh软件中的Geom和Tool等子面板建立新增附属结构的几何模型,并剖分为三维有限元模型,进而与AutoCAD软件进行比较。结果表明,利用HyperMesh软件对复杂结构进行补充修改几何模型,可大幅提高建模效率。

关键词： HyperMesh AutoCAD软件结构有限元建模 Software Based Complex Structure 三维有限元模型几何模型有限元结构分析混凝土结构双曲拱坝结构复杂建模效率复杂结构附属结构补充修改软件中李家峡剖分面板

Detection of subcritical crack propagation for concrete dams

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Science china(Technological Sciences) 2009年第12期52卷 3654-3660页

作者： BAO TengFei1 ,2&YU Hong 1,2 1College of water Conservancy&Hydropower engineering,hohai university,nanjing 210098,china 2national engineering research center of water resources efficient utilization and engineering safety,nanjing 210098,china College of water Conservancy & Hydropower engineering Hohai University Nanjing 210098 China national engineering research center of water resources efficient utilization and engineering safety Nanjing 210098 China

Subcritical propagation of cracks is a warning sign of *** such propagation is detected at an early stage,timely maintenance measures can be taken to prevent the failure of *** detect the subcritical propagation of a crack,the crack needs to be monitored continuously in a long term, which is not realistic under certain ***,cracks in concrete dams can be monitored continuously by dam monitoring to offer possible detection for subcritical *** this paper, with measured crack openings from dam monitoring,a state equation for characterizing crack development is established based on the grey system *** relation between the stability of the equation and the subcritical crack propagation is investigated,then a criterion is proposed for detecting subcritical *** example demonstrates the validity of the criterion and its potential for practical application.

关键词： crack subcritical propagation criterion concrete

Assessment model of dam operation risk based on monitoring data

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Science china(Technological Sciences) 2007年第z1期50卷 144-152页

作者： WU ZhongRu1,2?, SU HuaiZhi1,2 & GUO HaiQing1 1 College of water Conservancy and Hydropower engineering, hohai university, nanjing 210098, china 2 national engineering research center of water resources efficient utilization and engineering safety, nanjing 210098, china 1. College of water Conservancy and Hydropower engineering Hohai University Nanjing 210098 China 2. national engineering research center of water resources efficient utilization and engineering safety Nanjing 210098 China

Although the dams produce remarkable social and economic benefits, the threat made by unsafe dams to the life and property of people who live in the lower river area is un-negligible. Based on the monitoring data which reflect the safety condition of dams, the risk degree concept is proposed and the analysis system and model for evaluating risk degree (rate) are established in this paper by combining the reliability theory and field monitoring data. The analysis method for risk degree is presented based on Bayesian approach. A five-grade risk degree system for dam operation risk and corresponding risk degree is put forward according to the safety condition of dams. The operation risks of four cascade dams on some river are analyzed by the model and approach presented here and the result is adopted by the owner.

关键词： dam monitoring data operation risk degree analysis model

Analysis of crack propagation in concrete structures with structural information entropy

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Science china(Technological Sciences) 2010年第7期53卷 1943-1948页

作者： BAO TengFei1’2, PENG Yan1’2, CONG PeiJiang1’2 & WANG JiaLin1’2 1 State Key Laboratory of Hydrology-water resources and Hydraulic engineering, hohai university, nanjing 210024, china 2 national engineering research center ofwater resources efficient utilization and engineering safety, hohai university, nanjing 210024, china 1. State Key Laboratory of Hydrology-water resources and Hydraulic engineering Hohai University Nanjing 210024 China2. National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210024 China

The propagation of cracks in concrete structures causes energy dissipation and release, and also causes energy redistribution in the structures. Entropy can characterize the energy redistribution. To investigate the relation between the propagation of cracks and the entropy in concrete structures, cracked concrete structures are treated as dissipative structures. Structural information entropy is defined for concrete structures. A compact tension test is conducted. Meanwhile, numerical simulations are also carried out. Both the test and numerical simulation results show that the structural information entropy in the structures can characterize the propagation of cracks in concrete structures.

关键词： crack entropy concrete sun

A new method of estimating the equivalent elastic modulus of RCCD

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Science china(Technological Sciences) 2007年第z1期50卷 136-143页

作者： GU ChongShi1,2?, WU Yuan1, SU HuaiZhi1,2 & TANG LiHui1 1 College of water Conservancy and Hydropower engineering, hohai university, nanjing 210098, china 2 national engineering research center of water resources efficient utilization and engineering safety, nanjing 210098, china College of water Conservancy and Hydropower engineering Hohai University Nanjing 210098 China national engineering research center of water resources efficient utilization and engineering safety Nanjing 210098 China

Based on the composite material mechanic theory, the analysis method for the equivalent elastic moduli which are parallel and vertical to the construction interface of RCCD is studied in this paper. The differences between the equivalent elastic moduli which are vertical to the construction interface of RCCD gotten from different methods are discussed in detail. The variation range of the equivalent elastic modulus which is vertical to the construction interface of RCCD is studied based on the principle of minimum complementary energy and the principle of minimum potential energy. The effect of the related influential factors on the equivalent elastic modulus is analyzed. The estimation formula of the equivalent modulus which is vertical to the construction interface of RCCD is proposed. The feasibility of the approach proposed in this paper is analyzed through an example.

关键词： RCCD equivalent elastic modulus variation range estimation method

Review on hidden trouble detection and health diagnosis of hydraulic concrete structures

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Science china(Technological Sciences) 2007年第z1期50卷 34-50页

作者： WU ZhongRu1,2?, LI Ji1, GU ChongShi1,2 & SU HuaiZhi1,2 1 College of water Conservancy and Hydropower engineering, hohai university, nanjing 210098, china 2 national engineering research center of water resources efficient utilization and engineering safety, nanjing 210098, china College of water Conservancy and Hydropower engineering Hohai University Nanjing 210098 China national engineering research center of water resources efficient utilization and engineering safety Nanjing 210098 China

A large number of hydraulic concrete structures have hidden defects such as cracks, erosion, freeze and thaw, thermal fatigue, carbonization. These hidden defects seriously affect the strength, stability and durability of structures. These problems are studied mainly by single monitoring or diagnosis methods at present. The integration of multiple monitoring and diagnosis methods is not applied widely. Besides, the analysis theory on these problems is not developed very well. The systemic study on the aging mechanism of hydraulic concrete structures, time- variation model and health diagnosis is still not enough. The support for engineering practice is limited. Aimed at these major scientific and technological problems and combined with specific projects, study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out. This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures, seepage detection, the construction of in-situ sensing system, the combination of field detection and in-situ monitoring, the mechanism of crack, freeze and thaw, erosion and carbonization of hydraulic concrete structure, mechanism of combination aging; time-variation model of hydraulic concrete structure, theories and methods for health diagnosis of hydraulic concrete structures.

关键词： hydraulic concrete structure hidden trouble detection health diagnosis