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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 116024,china department of civil {2. Dalian University of Technology Dalian 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

LEVEL SET METHOD FOR TOPOLOGICAL OPTIMIZATION APPLYING TO STRUCTURE, MECHANISM AND MATERIAL DESIGNS

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Chinese Journal of Mechanical engineering 2004年第2期17卷 200-209页

作者： Mei Yulin Wang Xiaoming department of Mechanical engineering,{2. university of technology,{2. 116024,china department of Mechanical engineering Dalian University of Technology Dalian 116024

Based on a level set model, a topology optimization method has been suggestedrecently. It uses a level set to express the moving structural boundary, which can flexibly handlecomplex topological changes. By combining vector level set models with gradient projectiontechnology, the level set method for topological optimization is extended to a topologicaloptimization problem with multi-constraints, multi-materials and multi-load cases. Meanwhile, anappropriate nonlinear speed, mapping is established in the tangential space of the activeconstraints for a fast convergence. Then the method is applied to structure designs, mechanism andmaterial designs by a number of benchmark examples. Finally, in order to further improvecomputational efficiency and overcome the difficulty that the level set method cannot generate newmaterial interfaces during the optimization process, the topological derivative analysis isincorporated into the level set method for topological optimization, and a topological derivativeand level set algorithm for topological optimization is proposed.

关键词： Level set method Topology optimization Mean curvature flow Materialdesign Mechanism design Topological derivative

Changing Rule of Carbon-Enriched Zone and Diffusion Behavior of Carbon in Aging 0Cr6Mn13Ni10MoTi/1Cr5Mo Dissimilar Welded Joints

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Journal of Materials Science & technology 2004年第3期20卷 307-310页

作者： Zheng LIU Ligang WANG Lai WANG department of Materials engineering,{2., dalian 116024,china Dept. of Mat. Eng. Dalian Univ. of Technol. Dalian 116024 China

The microstructures, the changing rule of carbon-enriched zone, the diffusion behaviors of elements C and Cr, and thecarbide type of 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints after aging at 500℃ for various times and afterlong-term service in technical practice were investigated by using the optical microscopy electron probe microanalysis,scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that in aging0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints, the main carbides are M_3C and a few carbides are M_7C_3 andM_(2.)C_6. The M_3C carbide decomposition and dissolution with increasing aging time or aging temperature and theanti-diffusion of C and Cr cause the decrease and disappearance of the carbon-enriched zone. The results are differentfrom those of the A302.1Cr5Mo dissimilar welded joints in previous studies.

关键词： Dissimilar welded joint Aging Diffusion Carbides

Wave-current forces on bipiles in parallel array

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Acta Oceanologica Sinica 1992年第3期11卷 453-462页

作者： Li Yucheng, Wang Fenglong and Wang Hongrong department of civil {2., dalian university of technology, dalian 116024, china

-The inline and lift forces on bipiles in parallel array induced by both irregular waves and currents were investigated experimentally in this paper. The characteristics in both time and frequency domains of inline, lift and resultant forces as well were analyzed. The grouping effect coefficients of inline and resultant forces on two piles related to KC number and relative spacing parameters are given. A comparison of the magnitude and direction of resultant forces on two piles in parallel array with the corresponding values for single cylinder is also made.

关键词： Wave-current forces on bipiles in parallel array

COMPUTATION OF FREE SURFACE FLOWS WITH HIGH RESOLUTION FINITE ELEMENT SCHEME

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Journal of Hydrodynamics 2003年第3期15卷 22-27页

作者： Jin Sheng, Zhang Ri-xiang, Pu Gao-jun department of civil {2., State Key Laboratory of Offshore {2., dalian university of technology, dalian 116024, china, Lab. of Offshore Eng. Dept. of Civil Eng. Dalian Univ. of Technol. Dalian 116024 China

A high-resolution finite element scheme is developed for the computation offree surface problems. The present higher-order accuracy scheme is obtained through the introductionof the difference of almost equal amount of diffusion and antidiffusion, where the antidiffusion isformulated as approximation to diffusion making use of consecutive gradient. The non-oscillatoryproperties are secured by limiters to preserve positivity constraints. The implement of the schemeis based on semi-discrete form and can be considered as reconstruction of the coefficient matrix ofalgebraic system, so, it can he conveniently used by either structured or unstructured meshes. Thepower and flexibility of the present high resolution VOF-FEM approach is validated by examplesincluding convective transport, dam breaking flow, and stilling basin flow in hydraulic engineering.

关键词： free surface flow high resolution finite element scheme

Fractal Dimension Analysis of the Fine Aggregate Gradation of Interlocking Skeleton Asphalt Mixture

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Journal of Wuhan university of technology(Materials Science) 2011年第3期26卷 567-572页

作者：刘慧 School of civil & Hydraulic engineering Dalian University of Technology

By analyzing the fine aggregate gradation scales from standards,fine aggregate in the asphalt mixture is regarded as a whole research object and fractal dimensions X of the samples were obtained by linear regression and（AC-13）is 2.43-2.56,Sup-13 is 2.2.-2.54,SMA-13 is 2.66-2.88 and SAC-13 is *** the dense gradation mixture,there are little different between fractal dimensions of coarse and fine aggregates but it makes sense for skeleton asphalt *** a given coarse aggregate gradation and the same percentage of coarse aggregates,the compressive strengths and splitting strengths of the asphalt mixture are studied when the fractal dimensions are selected as 2.60,2.65 and 2.70,*** asphalt-stone ratio is less than optimal asphalt-stone ratio,the higher compressive strength is,the bigger X can be *** asphalt-stone ratio is larger than optimal asphalt-stone ratio,little difference of compressive strength can be observed under these three *** largest splitting strength can be got when X is 2.65,and larger splitting strength can be observed with the ascending of the asphalt-stone ratio.

关键词： fractal dimension fine aggregate gradation compressive strength splitting strength

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

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,{2. 2.department of Applied Mathematics,dalian university of technology,dalian 116024,{2. College of Information Sciences and engineering Shandong Agricultural University Tai’an China department of Applied Mathematics Dalian University of Technology Dalian 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

The Micro/Nanostructure Characteristics and the Mechanical Properties of Hemifusus tuba Conch Shell

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Journal of Bionic engineering 2010年第4期7卷 3+308-313页

作者： Yan Liang~1,Jie Zhao~2.Chengwei Wu~1 1.State Key Laboratory of Structural Analysis for Industrial Equipment,department of engineering Mechanics,{2. university of technology,{2. 116024,P.R.china 2.School of Materials Science and engineering,{2. university of technology,{2. 116024,P.R.china State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian P. R. China School of Materials Science and engineering Dalian University of Technology Dalian P. R. China

The mollusk shell mobilizes calcium from environment for skeletal *** occurs through synthesizing solidsin solution in the presence of organic molecules of specific interior regions of the conch *** ultrastructure and microhardnessof the Hemifusus tuba conch shell living in the Huang/Bo sea area are investigated in the *** is shown that thecomposition and microstructure of the mollusk shell vary in different *** prodissoconch shell consists only of aragonitewith the crossed-lamellar *** the spiral shell and the body shell of the Hemifusus tuba conch shell arecomposed of one calcite layer and several aragonite *** calcite layer consists of cylindrical grains,but the aragonitelayers are crossed-lamellar ultrastructure at three size *** minimum structure size (the third-order lamella) is at about2. nm - 80 *** margin of shell aperture is only composed of calcite with cylindrical *** natural optimization of theshell microstructure is intimately due to the growth of the Organic *** different positions the microhardness of molluscshell is different due to different crystal structures and crystal *** growth process of shells allows a constantrenewal of the material,thus enabling their functional adaptation to external environments.

关键词： conch shell microstructure aragonite calcite crossed-lamellar