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A Mechanical Model for Three-phase Permanent Deformation of Asphalt Mixture under Repeated Load

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Journal of wuhan University of technology(Materials Science) 2009年第6期24卷 1001-1003页

作者：赵永利 School of transportation Southeast University

On basis of the Burgers model, a new model consisting of modified dashpot and Van Der Poel model was derived from rheological and viscoelastic theory. Subsequently, triaxial repeated load permanent deformation tests of AC16 asphalt mixtures were conducted to validate this new developed model. Parameters of new developed model were obtained by a nonlinear regression analysis of test data, and then permanent strains and flow number of each mixture were calculated. The experimental results prove that the new developed model can well describe three phases permanent deformation of asphalt mixture under repeated load and it can be used for pavement mechanical analysis and rutting prediction.

关键词： asphalt mixture permanent deformation three phases theory triaxial repeated load

Discrete Element Modeling of Asphalt Concrete Cracking Using a User-def ined Three-dimensional Micromechanical Approach

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Journal of wuhan University of technology(Materials Science) 2011年第6期26卷 1215-1221页

作者：陈俊 college of Civil and transportation Engineering Hohai University

We established a user-defined micromechanical model using discrete element method （DEM） to investigate the cracking behavior of asphalt concrete （AC）. Using the ＂Fish＂ language provided in the particle flow code in 3-Demensions （PFC3D）, the air voids and mastics in asphalt concrete were realistically built as two distinct phases. With the irregular shape of individual aggregate particles modeled using a clump of spheres of different sizes, the three-dimensional （3D） discrete element model was able to account for aggregate gradation and fraction. Laboratory uniaxial complex modulus test and indirect tensile strength test were performed to obtain input material parameters for the numerical simulation. A set of the indirect tensile test were simulated to study the cracking behavior of AC at two levels of temperature, i e, -10 ℃ and 15 ℃. The predicted results of the numerical simulation were compared with laboratory experimental measurements. Results show that the 3D DEM model is able to predict accurately the fracture pattern of different asphalt mixtures. Based on the DEM model, the effects of air void content and aggregate volumetric fraction on the cracking behavior of asphalt concrete were evaluated.

关键词： discrete element method asphalt concrete cracking behavior three-dimensional simulation micromechanics

Research for Rear-End and Red-Light Running of Signalized Intersection

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Research for Rear-End and Red-Light Running of Signalized In...

Effects of Curing Systems on Properties of High Volume Fine Mineral Powder RPC and Appearance of Hydrates

工程和商业管理国际学术会议

作者： Jie Liu Hui-yuan Jiang college of transportation {2. University of technology {2. 430063 china

Signalized intersection of the road is an important hinge in the city. In our country, most of signalized intersection of the road exist the Rear-End and Red-Light Running. This paper addressed the security of signalized intersection, proposed the ’dilemma zone’ which existed in front of the signalized intersection, and aimed at the impact of the driver in ’dilemma zone’, proposed the measures of designing the route models and setting location marks in the ’dilemma zone’ to improve the safety of signalized intersection and reduce traffic accidents.

关键词： intersection rear-end and red-light running dilemma zone sign safety

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Journal of wuhan University of technology(Materials Science) 2010年第4期25卷 619-623页

作者：刘娟红 college of Civil and Environmental Engineering University of Science and Technology Beijing

The effects of different curing systems on the properties of high volume fine mineral powder RPC （reactive powder concrete） and the appearances of hydrates were studied. The experimental results show that dry-heating curing promotes the development of pozzolanic reactivity of fine mineral powder; due to low cement content, 0.2. water-bind ratio and high reactive fine mineral powder content, the strength of RPC increases by around 2.0% after steam curing and subsequent dry-heating curing. Scanning electron microscopy and energy spectrum diagram showed that： after the high volume fine mineral powder RPC with 0.16 water-bind ratio underwent steam curing and dry-heating curing, there was no significant change in the appearance of hydrates; after the RPC with 0.2. water-bind ratio, the cement content of 150 kg/m3 and more steel slag powder underwent dry-heating curing, there was a certain change in the appearance of C-S-H, the structure of gel was more compact and was uniformly distributed, and the Ca/Si of C-S-H gel decreased from 1.41 to around 1.2..

关键词： curing system high volume fine mineral powder RPC appearance of hydrates

Bionic Design and Finite Element Analysis of Elbow in Ice transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3, Linjing Xiao~3 1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, china), Shandong University of Science and technology, Qingdao 2.6510, P. R. china 2. School of Architecture, Tsinghua University, Beijing 100084, P. R. china 3. college of Mechanical and Electronic Engineering, Shandong University of Science and technology, Qingdao 2.6510, P. R. china Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education China) Shandong University of Science and Technology Qingdao P. R. China School of Architecture Tsinghua University Beijing P. R. China college of Mechanical and Electronic Engineering Shandong University of Science and Technology Qingdao P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

Life cycle assessment for the "implicit" environmental impact of construction projects

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Journal of Pharmaceutical Analysis 2009年第3期21卷 167-171页

作者： Xiao-gen Shuai1,2.Hui-qiang Li1,2.Li Tang1,31. School of Civil Engineering and Mechanics,Huazhong University of Science & technology,wuhan 430074 2. Hubei Key Laboratory of Control Structure,Huazhong University of Science & technology,wuhan 430074,china 3. Bartlett School of Graduate Study,University college London,London WC1E 6BT,UK. School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology Wuhan 430074 China Bartlett School of Graduate Study University College London London WC1E 6BT United Kingdom

The paper has established an assessment system and a quantitative calculation method of the 'implicit' environmental impact including environmental impact indicator,resources consumption indicator and energy consumption indicator. The quantitative calculation of the environmental impact indicator is based on the life cycle assessment system and the evaluation software BEES. The paper identifies normalization reference values and weights for 12.categories of the environmental impact. It also analyzes the environmental impact indicator in life cycle stages,raw materials,transportation,manufacturing,utilization,and end of life. A university refectory project is studied. The result has shown that human health,global warming and acidification are the first three environmental impacts in 12.categories. The environmental impact indicator per m2.of this project is 18.448×10-2.standard human equivalent weight. Moreover,97.3% of the total environmental impact occurs at the raw material stage,in which the most severe environmental impact is cancerous health effect; the global warming is the main impact at the transportation and manufacturing stages; the indoor air quality impact is at the usage stage.

关键词： life cycle assessment environmental impact implicit environmental impact BEES software

Study the Application of Neural Network in the Prediction of Regional Integrated Transport Structure

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Study the Application of Neural Network in the Prediction of...

Experimental Study of RC Beams Strengthened with CFRP Sheets Under Sustaining Loads

2.04 International Symposium on Distributed Computing and Applications to Business, Engineering and Science

作者： Huiyuan Jiang Jiang Li transportation college {2. University of Science and technology {2. Hubei Province 430063 china

＜正＞Each transport method in the transport system has its own technical economic characteristics and application range. However,in the past,each transport method was usually investigated separately in the quantitative analysis of transportation development *** obviously has some *** it is always a technological problem to analyze the development trend of the comprehensive transportation structure with mutual effect of each transport *** presence of the artificial neural network provides us a new way to resolve this *** the BP network is suitable for the short-term estimate,after its self-adapting in algorithm and error correction it can also be suitable for the long-term *** article establishes a neural network model according to the principle of artificial neural network, for the structure prediction of the comprehensive transport freight transportation volume and the freight transportation *** have displayed the running result of the model which has been proved to conform to the natural law of transport economic development with an example of the comprehensive freight transport system in a Province. Therefore,the BP network is more suitable to the multi-factor complicated transport system,which is unable to be expressed or analyzed by overt formulas.

关键词： Neural Network Integrated Traffic Cargo Structure Forecast

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Journal of wuhan University of technology(Materials Science) 2006年第3期21卷 82-85页

作者：王文炜 transportation college Southeast UniversityNanjing 210096China

Seven reinforced concrete （ RC ） beams strengthened in flexure using carbon fiber reinforced polymer （CFRP） sheets subjected to different sustaining loads were tested. The effects of initial load and load history on the ultimate strength of strengthened RC beams were examined by externally bonded CFRP sheets. The main experimental parameters included different levels of sustaining load at the time of strengthening, and load history. Experimental results show that sustaining load levels at the time of strengthening have important influences on the ultimate strength of strengthened RC beams. If the initial load is the same, the ultimate strength of RC beams strengthened with CFRP sheets is almost the same regardless of load history at the time of strengthening.

关键词： CFRP RC beams sustaining load experimental study

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集装箱港口物流系统仿真和优化研究综述

系统仿真学报 2009年第8期21卷 2119-2124,2159页

作者：蔡芸霍永忠武汉科技大学机械自动化学院武汉430081 武汉科技大学现代教育信息中心武汉430081

为了节省费用和快速有效地满足集装箱运输的需求,缩短船舶在港停泊时间,高效利用人力、泊位、堆场和装卸设备等资源,近年来,仿真技术和优化技术越来越多地被集装箱码头的设计者和管理者用来解决集装箱港口物流系统决策问题。归纳了在国... 详细信息

为了节省费用和快速有效地满足集装箱运输的需求,缩短船舶在港停泊时间,高效利用人力、泊位、堆场和装卸设备等资源,近年来,仿真技术和优化技术越来越多地被集装箱码头的设计者和管理者用来解决集装箱港口物流系统决策问题。归纳了在国内外集装箱港口物流系统研究中采用的仿真技术和优化技术,分析了它们在集装箱港口规划设计和运营管理决策中的研究现状和存在问题,展望了集装箱港口物流系统仿真技术和优化技术研究的发展趋势并具体地指出了一些需要进一步研究的课题。

关键词：仿真优化规划决策集装箱码头