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Computer Modeling in engineering & Sciences 2025年第1期142卷 691-712页

作者： Quynh-Anh Thi Bui Dam Duc Nguyen Hiep Van Le Indra Prakash Binh Thai Pham civil engineering department University of Transport Technology54 Trieu KhucThanh XuanHanoi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India

Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement *** study used three Machine Learning(ML)models,including K-Nearest Neighbors(KNN),Extra Trees(ET),and Light Gradient Boosting Machine(LGBM),to predict SBS based on easily determinable input ***,the Grid Search technique was employed for hyper-parameter tuning of the ML models,and cross-validation and learning curve analysis were used for training the *** models were built on a database of 240 experimental results and three input variables:temperature,normal pressure,and tack coat *** validation was performed using three statistical criteria:the coefficient of determination(R2),the Root Mean Square Error(RMSE),and the mean absolute error(MAE).Additionally,SHAP analysis was also used to validate the importance of the input variables in the prediction of the *** show that these models accurately predict SBS,with LGBM providing outstanding ***(Shapley Additive explanation)analysis for LGBM indicates that temperature is the most influential factor on ***,the proposed ML models can quickly and accurately predict SBS between two layers of asphalt concrete,serving practical applications in flexible pavement structure design.

关键词： Shear bond asphalt pavement grid search optimization machine learning

Dynamic Properties of Concrete under Severe Environmental Condition

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 877-882页

作者：闫东明 department of hydraulic and Environmental engineering Zhengzhou University department of civil and hydraulic engineering Dalian University of Technology

Exposure to environmental conditions can significantly influence the mechanical behavior of concrete structures in civil engineering. In this study, the effect of environmental factors, such as moisture and temperature, on the strain-rate sensitivity of concrete mixtures was systematically investigated. The strain rate varied from 10^-5s^-1 to 10^-2s^-1. From the investigation it was concluded that moisture content had a significant influence on the strain-rate sensitivity of concrete. With regard to concrete with low moisture content, temperature had little influence on the rate-dependent behavior; while for fully saturated specimens, a significant influence was observed. These phenomena were attributed to the meso-scale bonding properties of the concrete matrix. Equations were derived to characterize the ultimate strength increment of concrete with strain rate under different environmental conditions. An explanation to the dynamic failure mechanisms of concrete based on the experimental findings was proposed.

关键词： concrete strain rate moisture content temperature failure mechanism

River management system development in Asia based on Data Integration and Analysis System(DIAS) under GEOSS

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Science China Earth Sciences 2015年第1期58卷 76-95页

作者： Toshio KOIKE Petra KOUDELOVA Patricia Ann JARANILLA-SANCHEZ Asif Mumtaz BHATTI Cho Thanda NYUNT Katsunori TAMAGAWA department of civil engineering River and Environmental Engineering Laboratorythe University of Tokyo department of civil and Environmental engineering Hydraulic Engineering LaboratoryHiroshima University

This paper introduces the process of development and practical use implementation of an advanced river management system for supporting integrated water resources management practices in Asian river basins under the framework of GEOSS Asia water cycle initiative （AWCI）. The system is based on integration of data from earth observation satellites and in-situ networks with other types of data, including numerical weather prediction model outputs, climate model outputs, geographical infor- mation, and socio-economic data. The system builds on the water and energy budget distributed hydrological model （WEB-DHM） that was adapted for specific conditions of studied basins, in particular snow and glacier phenomena and equipped with other functions such as dam operation optimization scheme and a set of tools for climate change impact assess- ment to be able to generate relevant information for policy and decision makers. In situ data were archived for 18 selected ba- sins at the Data Integration and Analysis System （DIAS） of Japan and demonstration projects were carded out showing poten- tial of the new system. It included climate change impact assessment on hydrological regimes, which is presently a critical step for sound management decisions. Results of such three case studies in Pakistan, Philippines, and Vietnam are provided here.

关键词： integrated water resources management tools climate change impact assessment Asian river basins Asian Water Cycle Initiative

Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake engineering and engineering Vibration 2024年第2期23卷 445-454页

作者： Li Yuchun Shen Chao Liu Wei Li Dong department of hydraulic engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

Leak Detection in Offshore Pipelines of Conveying Fluid

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海洋工程：英文版 2004年第2期18卷 327-333页

作者：李俊花崔莉 School of civil and hydraulic engineering

Leakage from pipelines has caused serious environmental pollution and economic losses. Usually, leak detection can reduce the damage. The paper mainly discusses a hydraulic gradient-based leak detection method. The basic idea is outlined first, followed by a description of a laboratory experiment in a water pipeline. Several pressure curves are established based on different leak locations under the condition of a constant total flow rate. It is demonstrated that the leak of a large leak quantity can be detected reliably by the hydraulic gradient method.

关键词： pipe leak detection

Experimental Study on Allowable Berthing and Mooring Conditions of An Oil Tanker

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海洋工程：英文版 2003年第1期17卷 61-70页

作者：张日向刘忠波张宁川韩丽华 School of civil and hydraulic engineering

When an oil tanker under the combined action of wind, waves and tidal current and is berthed or moored to a platform, the impact forces on the fenders and the tensile force in the mooring lines are important factors in the studies of berthing and mooring conditions. Based on the experiment of a berthing and mooring tanker model under the action of wind, wave and tidal current in the same direction, this paper studies the allowable berthing and mooring conditions by considering the tensile forces of mooring lines and impact forces on the fenders, as well as the impact energy on the fenders. And a method has been proposed here for motion amplitude analysis. A successful method to decrease impact forces on the fenders is put forward. Blowing in wind and blowing off wind and different angles between waves and the fenders are considered in the experimental study. In the berthing tests of the tanker model, the impact forces are measured and the impact energy is calculated, then the berthing conditions are determined. In the mooring tests of the tanker model, the mooring line tensile forces and impact forces are measured, and the allowable mooring conditions are given that will be useful to engineering design.

关键词： oil tanker berthing mooring model test

Aligned Ion Conduction Pathway of Polyrotaxane‑Based Electrolyte with Dispersed Hydrophobic Chains for Solid‑State Lithium–Oxygen Batteries

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Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑Chang Sung Gwang‑Hee Lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim department of Materials Science and engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Theory and practice of construction simulation for high rockfill dam

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Science China(Technological Sciences) 2007年第z1期50卷 51-61页

作者： ZHONG DengHua ZHANG Ping WU KangXin department of hydraulic and Hydroelectric engineering School of Civil EngineeringTianjin UniversityTianjin 300072China Department of Hydraulic and Hydroelectric EngineeringSchool of Civil EngineeringTianjin UniversityTianjin 300072China Department of Hydraulic and Hydroelectric EngineeringSchool of Civil EngineeringTianjin UniversityTianjin 300072China

Construction simulation for high rockfill dam (CSHRD) is the technology that takes advantage of computer simulation to observe and analyze a complex construction process, which is useful for construction design and management. In this paper, the domestic and oversea research status of CSHRD is reviewed firstly, along with introduction of their present achievements and deficiencies, and the CSHRD theory is also described. Then, considering the influence of many stochastic factors, integrated simulation for high rockfill dam construction (HRDC) is presented with technologies of cycle operation network (CYCLONE) and computer simulation. It rationally combines two subsystems in HRDC, namely haulage and placement of rockfill subsystem, which reflects the actual construction objectively. Important parameters, such as the haulage intensity and traffic density, are obtained, and the process of CSHRD is represented intuitively in dynamic visualization. All of these help engineers to make rapid decisions in HRDC scientifically.

关键词： high rockfill dam construction simulation cycle operation network visualization

A simplified method for analyzing the fundamental frequency of monopile supported offshore wind turbine system design

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Earthquake engineering and engineering Vibration 2018年第4期17卷 893-901页

作者： Yang Chunbao Wang Rui Zhang Jianmin School of civil engineering/State Key Laboratory of Hydroscience and engineering Department of Hydraulic Engineering Tsinghua University

Preliminary design of offshore wind turbines requires high precision simplified methods for the analysis of the system fundamental frequency. Based on the Rayleigh method and Lagrange’s Equation, this study establishes a simple formula for the analysis of system fundamental frequency in the preliminary design of an offshore wind turbine with a monopile foundation. This method takes into consideration the variation of cross-section geometry of the wind turbine tower along its length, with the inertia moment and distributed mass both changing with diameter. Also the rotational flexibility of the monopile foundation is mainly considered. The rigid pile and elastic middle long pile are calculated separately. The method is validated against both FEM analysis cases and field measurements, showing good agreement. The method is then used in a parametric study, showing that the tower length Lt, tower base diameter d0, tower wall thickness δt, pile diameter db and pile length Lb are the major factors influencing the fundamental frequency of the offshore wind turbine system. In the design of offshore wind turbine systems, these five parameters should be adjusted comprehensively. The seabed soil condition also needs to be carefully considered for soft clay and loose sand.

关键词： offshore wind turbine system fundamental frequency analytical method rotational foundation flexibility

A new weir surface repair layer with shock absorbing cushion design

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Earthquake engineering and engineering Vibration 2013年第3期12卷 487-496页

作者： Tse-Shan Hsu Yi-Lang Hsieh department of civil engineering Feng-Chia University Ph.D Program in civil and hydraulic engineering Feng-Chia University

A shock absorbing cushion has never been introduced into any traditional weir surface repair layer design. However, shocks induced by high discharge with heavy sediment can easily produce brittle fracture and peeling over a weir surthce repair layer as it is impacted by floods accompanied by particles of different sizes. In this study, transcending traditional designs, the authors developed a composite unit designed with a shock absorbing cushion that has performed well during field tests, proving that the weir body can be effectively protected even if the composite units are directly laid on a severely uneven weir surface repair layer.

关键词： shock absorbing cushion brittle fracture peeling weir