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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{2. 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^-2.^-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

Chuetsu earthquake damages in Niigata County of Japan

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Progress in Natural Science:Materials International 2007年第10期17卷 1255-1259页

作者： Li Hongnan1, Zhao Yangang2.and Wang Guoxin1(1. State Key Laboratory of Coastal and Offshore engineering, dalian university of technology,{2., China 2. department of civil and Architectural engineering, Nagoya Institute of technology, Nagoya 466-8555, Japan) State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024 China department of civil and Architectural{2. Nagoya Institute of Technology Nagoya 466-8555 Japan

An Earthquake ML=6.8 occurred on October 2., 2.04 in Chuetsu area of Niigata County in Japan, which caused 40 people dead, more than 4500 people injured and 1000000 people homeless; nearly 140000 buildings were damaged or collapsed. The estated total loss of this earthquake was about 3000 billions Yen. In this paper, we investigate the Chuetsu earthquake damage from different aspects, including the seismic outline, seismicity, intensity distribution, wave feature, damage analyses, and economic losses. Finally, experiences and lessons from the earthquake damage are given. The content in this paper may be a reference for structural seismic design and code modification.

关键词： Chuetsu earthquake seismic damage Niigata province in Japan.

Analytical theory of flexural behavior of concrete beam reinforced with textile-combined steel

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Science China(Technological Sciences) 2010年第6期53卷 1700-1710页

作者： XU ShiLang & YIN ShiPing department of civil{2.,dalian university of technology,dalian 11602.,China 1. department of civil{2. Dalian University of Technology Dalian 116024 China

Textile-reinforced concrete (TRC) is a new high performance cementitious composite material,which not only has superior corrosion resistance but also can effectively limit the development of concrete cracks and make the crack width and spacing of concrete become ***,due to the brittle feature of fiber materials,the TRC structural member has no distinct failure symptom when it arrives at its ultimate *** the same time,ordinary reinforced concrete (RC) elements have large dead weight and can not efficiently restrict the expansion of the main crack of structures because of the restriction of their special cover *** order to overcome the disadvantages of both the TRC and the RC,a new architecture reinforced with textile-combined steel is proposed in this study,making full use of the advantages of the above two *** cover concrete at the tension zone of an RC element is partially replaced with TRC and thus the steel reinforcements replaced with textiles are *** with the old one,the new structure has less dead weight and has the merits of service safety and good *** flexural development process of the proper beam with this new structure is investigated in this paper and based on the plane section assumption,analytical equations are derived by using nonlinear analysis theory,including the load-carrying capacity at different stages and moment-curvature relationship and mid-span deflection during the entire loading *** between the calculated and the experimental results reveals satisfactory agreement and thus verifies the feasibility of the equations.

关键词： textile-reinforced concrete limiting the crack beam reinforced with textile-combined steel flexural behavior analytical theory

Numerical simulation of the influences of sinker weight on the deformation and load of net of gravity sea cage in uniform flow

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Acta Oceanologica Sinica 2006年第3期25卷 125-137页

作者： LI Yucheng 1,2. , ZHAO Yunpeng 1 , GUI Fukun 1 , TENG Bin 1 , DONG Guohai 1 1. State Key Laboratory of Coastal and Offshore engineering, dalian university of technology,{2., China 2. R&D Center of civil engineering technology, dalian university, dalian 11662., China State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024 China

A numerical model for determining fishing net configuration and load is developed, based on the lumped masses method. The model is used to analyze the influences on the net of gravity sea cage by different sinker weights in uniform flow. The net of gravity sea cage is simulated under different current velocities and sinker weights. In order to verify the validity of the numerical results, model test results made by Lader and Enerhaug are cited and compared with the numerical ones. The results of numerical simulation agree well with the experimental ones and the agreement is within an error range of 13% under different velocities and sinker weights. The numerical results indicate that increasing the sinker weight can effectively reduce the net deformation, but the total drag force on the net will increase accordingly. Results will give references for better knowledge of the hydrodynamic behavior of gravity sea cage.

关键词： sea cage numerical simulation lumped mass method sinker weight

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2. Narve Ekrol 2.(1. department of Marine Environmental engineering,{2. Maritime university, dalian 11602., China E mail: deqi@*** 2. department of Environmental engineering, SINTEF Applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied Chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

A study of ice response spectra

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Acta Oceanologica Sinica 2009年第3期28卷 114-119页

作者： LIU Chunguang JIA Lingling State key Laboratory of Coastal and Offshore engineering Dalian University of TechnologyDalian 116024 China School of civil Hydraulic engineering Dalian University of Technology Dalian 116024 China

Some problems concerning the ice forces and ice response spectra are studied from both theoretical and practical points of view. On the basis of structural analysis,the analysis method of ice response spectra is proposed, since it plays an important role in the prediction of maximum structural response in cold regions. And it is illustrated that it is easy to study the structural response to ice using the ice response spectra.

关键词： ice force ice response spectra structural analysis ice-induced vibration

The optimization of DNA encodings based on GA/SA algorithms

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Progress in Natural Science:Materials International 2007年第6期17卷 739-744页

作者： Wang Wei1, Zheng Xuedong2. Zhang Qiang1 and Xu Jin2.1. Liaoning Key Laboratory of Intelligent Information Processing, dalian university, dalian 11662., China 2. department of Control Science and engineering, Huazhong university of Science and technology, Wuhan 430074, China) [a]Liaoning Key Laboratory of Intelligent Information Processing Dalian University Dalian China [b]department of Control Science and engineering Huazhong Univerisity of Science and Technology Wuhn China

The design of DNA sequence plays an important role in improving the reliability of DNA computation. Proper constrained terms that DNA sequence should satisfy are selected, and then the evaluation formulas of each DNA individual corresponding to the selected constrained terms are proposed. The heuristic improved genetic algorithm (GA)/simulated annealing (SA) algorithm is presented to solve the multi-objective optimize problem, and the DNA sequence design system is developed. Furthermore, an example is illustrated to show the efficiency of our method given here.

关键词： DNA encoding multi-objective optimize GA/SA algorithms

Nonsingularity in second-order cone programming via the smoothing metric projector

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Science China Mathematics 2010年第4期53卷 1025-1038页

作者： WANG Yun 1,& ZHANG LiWei 2.1 College of Information Sciences and engineering,Shandong Agricultural university,Tai’an 2.1018,China 2.2. of Applied Mathematics,dalian university of technology,dalian 11602.,China 1. College of Information Sciences and engineering Shandong Agricultural University Tai’an 271018 China2. Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker ***,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker ***,the analysis does not need the strict complementarity condition.

关键词： second-order cone programming problem smoothing metric projector B-subdifferential Clarke’s generalized Jacobian smoothing Newton method

Refraction-Diffraction Model for Irregular Wave and Directional Spectrum Considering Current

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China Ocean engineering 1996年第2期11卷 193-202页

作者： Li Yucheng and Zhang Yonggang Professor, department of civil{2., dalian university of technology, dalian 11602. Ph. D. Candidate, dalian university of technology, dalian 11602. department of civil{2. Dalian University of Technology Dalian 116023 dalian university of{2. Dalian 116023

A mild-slope equation for combined refraction and diffraction of random waves in the independent time current is derived using Kirby equation(1984). In the derivation, the frequency of random waves is represented based on the time series concept, by a typical frequency and its deviation part. Numerical results, compared with those of laboratory experiments, demonstrate that new set of irregular mild slope equation with current is of good adaptability.

关键词： wave rejraction-diff action irregular wave directional spectrum wave-current interaction simulation