bluuebunny/crossref_metadata_2025 huggingface dataset:
The Generation of a Three-Dimensional Aggregate Model for Concrete Based on Unity3D
Authors: Luo Bo Guang , Qin He Ying , Huang Chun Xiao
Published: March 2013

The simulation analysis is an important part of theoretical study on concrete materials. It is a kind of quantitative analysis method of making full use of the computer technology and it has the advantages of high efficiency, safety, fewer limits of environmental conditions, easy change of the time and size etc. Quickly generation of a three-dimensional aggregate structure is a very important prerequisite for the computer simulation analysis of concrete. In this paper, in order to meet the demand of analysis and simulation, based on the technology of Unity3D，the program of three-dimensional aggregate is written, designed to use a large number of existing tools to quickly generate a concrete aggregate model as simple as possible.
Application of Microsoft Agent in Humanized Courseware
Authors: Chen Yao Fei , Zheng Wei , Chen Huan Tong
Published: March 2013

Traditional courseware is lack of humanity. Proposes to use Agent technology achieve the humanized design in courseware. Microsoft Agent with its lively and clear human features has had a significant influence upon traditional human-computer interaction. This paper introduces the related technologies of Microsoft Agent, and discussed the realization of the principles and the design process of the Microsoft Agent in authorware . The paper gives the Agent script design structure, the human feedback of humanized courseware and the notes in the process. Microsoft Agent enhanced the expression and presentation effect of courseware by lively images of anthropomorphic expression, speech and action.
Evaluation on Engineering Geology Applicability for Urban Construction Land Based on GIS: Taking Zhengding New District of Shijiazhuang City for Example
Authors: Liu Chun Yuan , Sun Jian Zhu , Liu Yu
Published: March 2013

In this paper, taking the Zhengding new district of Shijiazhuang city as an example, we put forward to take advantages of analytic hierarchy process and rough set theory and combine them with fuzzy comprehensive evaluation method to do the quantitative analysis of suitability of the engineering geology conditions of urban construction land .It can make the evaluation more objective. This paper divides study area into the most suitable,suitable,less suitable and unsuitable,and provides a strong scientific basis for the design and planning.
Determining Method for Effective Length of Soft Ground in Tianjin Binhai
Authors: Shao Hong Tao , Yang Xiao Rong , Wang Yan Hong
Published: March 2013

Tianjin Binhai has the properties of poor geological conditions and much weak soil. Cement mixing pile is used to the bridges and the roadbed of channel and culverts in Tianjin Avenue projection. But there are some problems about the effective length. The cement mixing pile is considered to be pure friction pile when the length is shorter than the effective length. According to the displacement coordination condition of the top surface of the pile-soil under rigid foundation, the computing method of effective length for composite foundation is derived from the settlement.
Experimental Study on Evaluating High-Pile Wharfs for Real Ship Berthing Impact
Authors: Xie Yao Feng , Tang Wei Qing
Published: March 2013

High-pile wharf is the most frequently used wharf structure form on soil foundation. However, few researches have been conducted to establish field overall evaluation methods capable of determining the berthing capacity of high-pile wharfs. Based on finite element numerical simulation, the stress-deformation relation, and the equations for loading-deflection relation at the pile head are obtained. The method to test the actual berthing capacity for real ship impact on high-pile wharf，as a direct and effective test method，and the security evaluation of high-pile wharf is put forward. These results can be used for reference to test the actual berthing capacity and to evaluate the security of high-pile wharfs.
Experimental Study on the Process of Geomorphic Evolution of Debris Flow on Slope
Authors: Tang Hong Mei , Wen Guang Ju , Wang Lin Feng , Chen Hong Kai
Published: March 2013

To reveal the process of geomorphic evolution of debris flow on slope, the qualitative-semi-quantitative model experiment was built from experimental model, characteristics of soil and rainfall scheme. The results indicate that the essence of geomorphic evolution of debris flow on slope is the interaction of soil and water. And the change of geomorphology is reflected by the elevation of topsoil. In antecedent rainfall, the elevation of topsoil is in increasing trend generally except some parts. During short heavy rainfall, the soil creeps intensively, mixes with water and becomes fluidization gradually. The elevation of topsoil on the top is decreasing generally, while on the button, the elevation is increasing. Moreover, because water infiltrates into slope and interacts with soil needing a period of time, the change of geomorphology falls behind the rainfall process.
Estimation Theory on Cross-Sectional Area of Cables in Mega Steel Frame and Cable Bracing Structure
Authors: Gu Sheng , Tang Bai Jian , Wang Fei
Published: March 2013

The mega steel frame and cable bracing structure belongs to the pre-stressed high-rising building and how to estimate cross-sectional area of cables is one of key problems for this new structural system. Considering shear and bending deformation, the relationship between structural story drift and cross-sectional area of cables is established by using the superposition principle of deformation. Further, cross-sectional area of cables is determined based on the design target value of story drift that is known. The qualitative estimation method on cross-sectional area of cables is finally developed. The cross-sectional area obtained by using this method is its lower critical value, and the method presented is useful for the preliminary design and qualitative evaluation.
Experiment Research on Square Columns Reinforced by High Strength Wire Mesh Mortar
Authors: Dong Chun Min , Guo Ke Dong
Published: March 2013

To investigate the influence of wire mesh type, wrapped way and stress of column on the behavior of RC square columns, the experiment including an unreinforced column and 7 strengthened columns with the high strength wire mesh mortar were tested. The results were shown that the strength and axial deformation of columns reinforced by high strength wire mesh mortar were enhanced. Finally, the calculation formula for ultimate bearing capacity of the reinforced columns was given based on the test results, which agreed with the tested results well.
Experimental and Numerical Studies on the Joint of Special-Shaped Concrete-Filled Rectangular Composite Tubular Column with H-Shaped Beam
Authors: Liu Ji Xiong , Dai Shao Bin , Peng Yao , Huang Jun
Published: March 2013

3 extended-end-plate joints of T-shaped concrete-filled rectangular composite tubular column with H-shaped beam were designed. The experimental research and ANSYS nonlinear finite element analysis on the earthquake resistance behaviors of the joints were conducted under low cyclic loading. The results indicate that the shapes of hysteresis curve of each specimen is full and presents spindle, all the specimens possess good energy dissipation capacity. The end-plate thickness and high-strength bolt diameter have a great influence on the bearing capacity of the joints. Increasing the thickness of end-plate and the diameter of high-strength bolt, the displacement ductility factors of the joints decrease slightly, but their ultimate bearing capacities obviously enhance. The stress distributions and the finite element failure characteristics of the joints are basically consistent with the test phenomena, yield bearing capacity and ultimate bearing capacity of the finite element calculations can agree well with the experimental results.
Experimental Investigation into the Effect of Spring-Settlement Support on Bearing Capacity of the Shallow-Buried Structure
Authors: Zhang Wei Feng , Guo Zhi Kun , Ren Wang Jun , Wang Yong Hui , Cao Lan Fu , Li Yue Chi
Published: March 2013

Small span arch steel structures on spring-settlement support and normal support were designed as research objects. 1kg, 2kg, 3kg and 5kg TNT group charges were detonated respectively on the center surface of backfill above the structure. Numerous data was obtained during these tests. The comparisons of measured parameters were done between the structure with spring-settlement support and normal support. The results indicate that, the structure with spring-settlement support can reduce the magnitude of internal force of the structure, decrease the dynamic effects on the structure significantly, and enhance the bearing capacity.
Dynamic Effects on a Pre-Stressed Multi-Story Plane Steel Frame Caused by Sudden Failure of a Cable
Authors: Wang Fei , Tang Bai Jian
Published: March 2013

The dynamic effects on a pre-stressed multi-story steel plane frame caused by sudden failure of a pre-stressed cable were investigated by general finite element software. The stiffness reduction method was adopted to simulate sudden cable rupture, which can induce dynamic response of the pre-stressed multi-story plane frame. The numerical results show that the recommended failure time should be less than 1/20 of the fundamental period of the remaining structure to consider dynamic effects more accurately. As the failure time decreases, the amplitudes of structural top lateral displacement and internal forces at the column ends all increase and they decay more slowly. The dynamic coefficients of bending moment and shear force are larger than that of axial force at the column ends. The farther the beam is from the failed cable, the faster the bending moment at the beam end decays, and the larger its dynamic coefficient is.
Field Test Study on Frost-Heave of Subgrade in Seasonal Frozen Region along Haerbin-Dalian Passenger Dedicate Line
Authors: Hou Jin Fang , Wang Yong Li , Feng Jun
Published: March 2013

The new constructing railway Haerbin-Dalian Dedicate Line runs through the typical seasonal frozen region. For the purpose of estimating the quality of subgrade construction, a field test was played. Placed the monitoring instrument and measure the soil temperature, settlement and soil pressure etc.. The monitoring data shows that the change of soil temperature is less than the environment temperature. The maximum frost depth is 1.66m. In this depth, the fine-grained soil with high frost-heave characteristic should not be as the subgrade. The effective measure to prevent the rain percolated through the subgrade is important. And the filling of subgrade should be constructed strictly according to the maximal degree of compaction and keep the best water content. The settlement of subgrade is less than 15mm, the water content is also less than the prime frost-heave water content and the frost-heave force is very small. Thus, the construction technique subgrade is feasible.
Fatigue Behavior of Elastic Concrete-Steel Composite Beams
Authors: Wang Yi Hong , Han Qing Hua
Published: March 2013

As a new material type, elastic concrete has been used in pavement and bridge deck paving due to its superior properties to ordinary concrete. Nowadays, fatigue behavior of steel-concrete composite beams has become the focus in engineering design. This paper summarized the research status, methods, influence factors on fatigue behavior of elastic concrete and steel-concrete composite beams and compared various fatigue specifications among different countries. The result shows that elastic concrete has longer fatigue life than ordinary concrete, so we can solve fatigue problems by using elastic concrete instead of ordinary concrete in composite beams. Finally the author puts forward suggestions for further advanced study in this area.
Modal Analysis for Space Grid Structure under Different Supporting Conditions
Authors: Lv Yan , Wang Lai
Published: March 2013

The supporting conditions have important effects on deformation of grid structure. This paper takes a long-span space truss structure as the research object, and a modal analysis of the grid structure under different supporting conditions is carried out by the finite element software. It is found that the grid structure of trilateral supporting and both sides supporting has big deformation due to the existence of free edges, which is adverse to the deflection of grid structure. Therefore, free edges should be treated properly in practical engineering, in order to improve the stress states of grid structure. With the increase of order, the natural frequencies of grid structure under different supporting conditions grow incrementally through modal analysis. In the same order, the natural frequency of two sides supporting is minimum, while the peripheral supporting is maximum.
Numerical Analysis of Bearing Capacity to Q690 Tubular Joints Enhanced by Inner Sleeve
Authors: Li Li Yuan , Wan Li , Peng Yi Liang , Zhang Tao
Published: March 2013

Simple joint is a common connection in tubular structures, it refers to one or more components soldered directly on the surface of the other member. Local buckling occurs in panel zone when the joint under heavy load, such local buckling will reduce the bearing capacity and stiffness. In order to improve bearing capacity of tubular joints, the joint needs to be strengthened. In this paper, the bending performance of the joint will be enhanced by welding a sleeve inner the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different parameters of inner sleeve was analyzed. The results showed that compare to sleeve length variation, bearing capacity of the joint experiences obvious change with variation of sleeve thickness.
Parameter Sensitivity and Reliability Analysis for Construction Control of Cable-Net Structure Supporting the Reflector of FAST
Authors: Kong Xu , Wang Qi Ming , Liu Chuan Jia , Zhu Zhong Yi
Published: March 2013

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is supported by cable-net structure, which enables its surface to form a paraboloid in real time under active control. FAST is now entering project construction and implement stage, however there are always a considerable amount of errors existed in practice which would result in the deviation of the structure from its ideal model. Therefore, structural parameter sensitivity analysis was indispensable discussed. In the paper, the variation ranges of structural parameters were rationally determined. Base on local sensitivity analysis and global sensitivity analysis method, Using the finite element model investigated the influence of different structural parameters change on the static behavior, gets the conclusions that the impact of several key design parameters on the tension force of cable-net is large. The results indicate that of all types of the structural parameters, the error of the length of cable plays the most important role, and the global sensitivity analysis indicates that the tension force range of cable-net is -18% to 27%.
Research on Load Distribution Effect of Load Distributed Structure in the Complex Rotational and Translational Engineering
Authors: Wu Er Jun , Cao Zhao Na , Zhang Fen Fen , Wang Wei
Published: March 2013

In view of the large axial force column underpinning of the complex rotational transportation engineering，a new underpinning structure which with six diagonal bracings was proposed in this paper. Using SAP2000 software built four different calculating models with different support forms, and analyzed internal forces of members of the underpinning structure, discussed the load distribution effects on change of parameters including the inclined angle α between the inclined support and column, the angle θ between the inclined support horizontal projection and axis, inclined support section sizes, coupling beam section size and whether there are the horizontal forces. The results show that the load distribution effects of whole model and of single column model have little difference, but the single column model underestimates the axial forces of the inclined supports. α and θ have a great influence on load distribution effect, and smaller α is better. The load distributed result can be very good to meet the requirement of rotating shift engineering.
SAP2000 Analysis of a Particular Beam String Structure
Authors: Li Jia Qi , Zhao Chao Hua , Chen Yu Qian
Published: March 2013

The Beam String Structure was in short-side direction. This paper simulated Beam String Structure in long-side direction. Through SAP2000 analysis of vibration mode and stress of single and overall structure, some features of the structure were obtained. The single structure has small rigidity disadvantage, while the overall structure has reasonable stiffness. Then the paper draws a conclusion that disadvantage in long-side direction can be remedied by overall structure.
The Method of Sandwich Plate about Thin-Wall Cast-in-Site Reinforced Concrete Hollow Floor
Authors: Chen Ying Bo , Gong Da Lin , Chen Jun Ming
Published: March 2013

Treat the upper plate and lower plate of ribbed hollow floor as the surfaces of sandwich panel, and the ribbed hollow layer as the central layer of sandwich panel; consider the bending stiffness of the surfaces and transverse shear deformation of the central layer; use Hoff laminated theory; based on the same stiffness principle; establish sandwich panel structure model of hollow floor; Derive partial differential equations of cast-in-place reinforced concrete two-way ribbed and thin-walled hollow floor under vertical uniform load and present the analytic solution of the equations with two opposite clamped edges and others simply supported edges. Analyze the mechanical properties of hollow floor. The results are very close to the results of using finite element method.
The Performance Analysis of Calcium Silicate Composited Wall's Impact Resistance
Authors: Chen Ming Ming , Tao Zhong , Zhang Hen Min , Yu Wen Zheng
Published: March 2013

This paper introduces the impact experiment and an engineering application of the new composited wall which composed of calcium silicate composited board. Clearly defines the impact resistance of the wall in different connection as interior walls and exterior walls through observing the wall’s changes in the number of 5 times or even up to 50 times impact (10 times of the national standard). It can be known from the experiment that long wall has large vibration but good integrity. The window wall may fracture easily and is not able to meet the minimum standard requirements of impact resistance when the width is small. It needs to take reinforce measures.
The Research about the Method of Establishing the Model of Limited Unit about the Push-Extend Multi-under-Reamed Pile
Authors: Qian Yong Mei , Mu Nan , Wang Ruo Zhu
Published: March 2013

This paper mainly introduces how to use the method of combining plane coordinates and polar coordinate, and the method of using ANSYS software to establish the calculating model of the limited units about the Push-extend Multi-under-reamed Pile, at the same time, it is successfully provided that a method of building model of the limited units for computer simulation analysis of irregular rotator body.
Analysis and Test for the Space Different Thickness Film Structure in Still Air
Authors: Chen Yu Feng , Chen Wu Jun , He Yan Li
Published: March 2013

The air added mss have important influence on film modal. Based on the commercial finite element (FE) package ABAQUS, a numerical procedure for membrane mode analysis was set up and used to analyze a square film modal. The membrane pre-stress can be introduced through temperature load . The equilibrium shape of the space film was obtained through a geometrical nonlinear step .The dry and wet mode of the film structure was calculated and analyzed by means of the Lanczos method. The added mass above each vibration region is equal to the uniformly distributed air with height of 0.65l. The rectangular plane film test revealed the validity of the finite element simulation on the membrane structure base frequency. The film structure with edge cable is a rational structure form. The proposed analysis method and conclusion on the film structure modal analysis has the reference value.
Capacity Calculation on Reinforced Concrete Beams Strengthened by Externally Prestressed Transverse Tensioning Method
Authors: Tong You Zhi , Wang Tian Wen
Published: March 2013

Eight reinforced concrete beams (six externally reinforced and two contrast beams) were tested under the primary or secondary load experiment. According to the test results, the existing formulas and specifications were applied to make calculations on reinforced beams. Besides, comparisons were made between test and calculation value, the differences were pointed out and improvement measures were proposed. Comparisons were made between test and calculation value on normal section flexural bearing capacity of reinforced concrete beams strengthened by externally prestressed transverse tensioning method and they are in good agreement.
Compressive Testing of H-Shaped Steel Stub Columns Fabricated with Grade 800MPa High Performance Steel
Authors: Lee Kang Min , Lee Myung Jae , Oh Young Suk , Kim T.S. , Kim Do Hwan
Published: March 2013

With the increased demand for high-rise and long-span structures, high strength with high performance steels have been utilized for these kind of structures. For the grade 800MPa high performance steel, although it was included in Korean Standard as high strength steel(HSA 800), however the HSA 800 steel was excluded in Korean Building Code-Structures due to the rack of research results for the structural behaviors of members fabricated with HSA 800 steel. Therefore, this paper describes basic study for the design specification of structural members using HSA 800 high performance steel. For this purpose, welded H-shaped stub column specimens with various width-to-thickness ratios were designed and tested in order to investigate the buckling behaviors and ultimate compressive strength.
Damage Inspection and Assessment on a Transmission Angle Tower in Coastal Areas
Authors: Li Peng Yun , Chen Bo , Sun Yu Zhou
Published: March 2013

The field inspection and safety assessment of a transmission angle tower are actively carried out in this study. The field measurement and inspection are firstly introduced and then the structural model is constructed based on finite element approach with the aiding of commercial package ANSYS. The equation of motion of the transmission tower-line system is established for numerical analysis. The gravity, base settlement and dynamic wind loading are applied on the tower to examine the structural responses. The deformation and stresses distribution of the transmission angle tower are computed to explore the damage reasons. The made observations indicate that the peak stresses of some members are large than the permitted yielding stresses of steel material. The damage event is induced by coupling loading effects
Experimental Study on the Corrosion Rate of Rebars in Chloride-Contaminated Concrete with Adding or Painting Inhibitors
Authors: Yu Lei , Liu Zhi Yong , Sun Hao Xia
Published: March 2013

Tests were conducted to investigate the inhibiting effect on steel bars in concrete contaminated with 0.75% (wt.) chloride of the cementitious materials by adding inhibitor in green concrete or surface painting inhabitor on cover concrete. The results show that the anticorrosion effect of surface painting inhibitor on concrete with 30mm cover at 400g.m-2 are mainly better than that of adding 2% inhibitors in concrete with 0.75%(wt.) NaCl of the cementitious materials. The minimum corrosion current of steel bar in concrete sample after painting MCI-C12 28 days can be reduced to 0.084 μA.cm-2 from 1.30 μA.cm-2 of the sample before painting inhibitor. The corrosion current of steel bars in concrete samples painted with MCI-2010 and sodium nitrite solution are roughly equal to that of the control concrete sample without chloride, and less than that of the sample added in nitrite and chloride. Compared with mixed inhibitor in green concrete, surface applied inhibitor on hardened concrete not only avoid to affect the properties of concrete, but also bring to the visible economical advantage.
Nonlinear Analysis on Static Behaviors of New All-Bolted Beam-to-Column Connections for Concrete-Fillled Square Steel Tube
Authors: Zhao Xin , Wu Mai , Kong Dan Dan , Wu Nan
Published: March 2013

All-bolted steel beam-to-column connections for concrete-filled square steel tube (CFST) have the advantages of industry manufacture, being constructed quickly and easily concreting. The new design all-bolted connection discussed in this paper has the construction details of Π-shape plate and high strength bolts which connect the steel beam and CFST column. In order to investigate the static performances and failure modes of this new all-bolted connection, a full three-dimension ANSYS ﬁnite element (FE) model of the connection subjected to montonic load is built up. The theoretical values and experimental results are very close, that verifies the rationality of the FE models and the analysis method in this research. Further the calculated results demonstrated the new bolted connections belong to typical semi-rigid connection and have the superior static resistance in stiffness, strength, and rotating capacity.
Numerical Simulation Analysis of Auxiliary-Rod Force for Tower
Authors: Li Mei , Jin Xiao Jun , Li Yan Hui
Published: March 2013

Based on nonlinear FEA software ANSYS, thirty-six numerical simulation tower-models that have different initial bend state, bend deflection and intersegment of main-rod were established. Analysis results indicate: Initial bend state of main-rod has influence to force of horizontal auxiliary-rod greatly. With increasing initial bend deflection of main-rod, force of each horizontal auxiliary-rod presents to enlarge trend and is unequal. Force of each horizontal auxiliary-rod is less than 0.015 times endogen force of main-rod, total of each force for horizontal auxiliary-rod is less than 0.06 times endogen force of main-rod. With increasing intersegment of main-rod, total of each force for horizontal auxiliary-rod presents to enlarge trend.
Reliability and Resistance Statistical Analysis for the Structural Members of Cold- Formed Thin-Walled Structures
Authors: Huang Xue Fang , Shao Xin Yan
Published: March 2013

This study analyze the capacity formulae of the structural members whose stress are the compressing, pure bending and compression-bending, which are recommended in Chinese Unified Standard for The Reliability Design of Building Structure, by the first order second moment method. The analytical results indicate that the reliability indexes of the design formulae can meet the requirements of the Unified Standard for The Reliability Design of Building Structure (GB 50068-2001) for plastic material.
Numerical Simulation of Static Liquefaction in Tailings Pond
Authors: Liu Yang , Zhao Xue Tong , Yan Hong Xiang
Published: March 2013

Static liquefaction is one of the main causes of flow slide destruction in tailings pond. This paper analyzed the static liquefaction behaviors in tailings pond through the development of displacement, deformation and pore pressure ratio. Based on the simulation results, some conclusions were obtained. Fast discharge of tailings will fasten the increase of pore pressure. The dam-toe in tailings pond is very easy to be eroded, leading to introverted destruction. The liquefaction of sand layer in foundation would cause the tailings dam’s slip failure. With the arising of tailings, pore pressure increased continuously expanding to the foundation under the dam.
Strengthening and Retrofitting of the Industries Building After Fires
Authors: Liu Ming , Fan Xin Hai , Zuo Yong Zhi , Song Bao Feng
Published: March 2013

The reinforcement project is three-storey of the industries building, the total height of the industries building is 14,200mm, the clear height of one storey is 7,500mm, the building area is 1,500 square meters, structural mode is reinforced concrete frame structure. The structural members were damaged seriously due to fire In January 2010, strengthening the damaged members was proposed in order to ensure the safety of the structure. Enlarging section reinforcement method, Polymer Mortar and gluing CFRP methods were adopt to strengthen the beams, columns and floor slab depending on the damage degree of the concrete member.The idea of dealing with the industries building damaged by fire can provide us a good reference of repairing the similar industries building.
Stress Analysis of Steel Pipelines Strengthened by CFRP Sheet
Authors: Hou Mu Yi , Jia Bin , Liu Shun Feng , Chen Xiao Qiang
Published: March 2013

Carbon fiber reinforced polymer sheet has advantages of light weight, high tensile strength and excellent corrosion resistance [1]. Compared with traditional metal piping reinforcement, CFRP reinforcement method is a new and advanced method. This paper which based on the Lame equation deduce the hoop stress formula of the steel pipelines strengthened with CFRP sheet winding when subject the internal pressure. It is available for the research of steel pipelines strengthened with CFRP sheet.
Structural Flexural Bending Assessment of Prestressed Concrete Joist with Corrosion
Authors: Vercher Jose , Gil Enrique , Mas Ángeles , Lerma Carlos
Published: March 2013

The number of situations where it is necessary to intervene in existing structures is increasing. In Spain, rehabilitation and maintenance of buildings accounts for 30% of the activity of the construction sector and it is growing. This paper evaluates the residual safety of T prestressed joists with severe corrosion at the lower reinforcement. The reliability is assessed with the application of the ACI-318 load test. It is demonstrated that there is sufficient safety in cases of corroded prestressed joists. At any rate, it’s recommended to make a light repair under the damaged joists.
Nonlinear Numerical Analysis of Transfer Beam Under Complex Situation
Authors: Chen Jin , Jiang Shi Yong , Jiang Zheng , Zeng Xiang Rong , Zhang Lei , Luo Wen
Published: March 2013

Taking a transfer beam of high-rise building in the actual engineering as an example, nonlinear numerical analysis on transfer beam structure,which is several complex stress situation about eccentric and different sizes of eccentricity of the upper short limb shear wall , is carried by the finite element software ANSYS, its stress performance and deformation characteristics are studied. Analysis results show that: (1)impact of eccentricity of the upper short limb shear wall on stress performance of transfer beam is very big, which is more unfavorable than that of no eccentric. Eccentric made structure be under stress state of bending, shear, torsion. (2)The eccentricity increased more significant effect on the displacement of transfer beam, and bigger effect on reliability under normal conditions. (3)Both from view of the design point, or from view of the economic point, the wall eccentric action in transfer beam should be avoided as far as possible to meet the construction requirements.
Elastic Modulus Reduction Method Based Limit Analysis of Steel Lined Reinforced Concrete Penstocks Containing Flaws
Authors: Liu Shu Lin , Fu Chuan Xiong , Zhang Wei
Published: March 2013

In the context of ultimate bearing capacity of steel lined reinforced concrete penstock (SLRCP) containing flaws, the use of the elastic modulus reduction method (EMRM) in conjunction with curve beam based internal force calculation is presented. The corrosion models for steel bar and lining are introduced from the literature. The SLRCP is considered bearing load together with lining and reinforced concrete, and its internal force is determined based on a simplified curve beam model. The element bearing ratio of SLRCP is given through the internal force and sectional strength, and is employed by the EMRM. The change of ultimate bearing capacity of some typical SLRCP within their operating life is then evaluated.
A Study on the Effects of Wake Vortex to the Aero-Elastic Parameters of Downstream Square Prism
Authors: Chen Jwo Hua
Published: March 2013

A series of aero-elastic experiments were conducted to identify the aero-elastic parameters of 2-D square prisms under the interference effects of the tandem arranged upstream prism wake. The wake induced across-wind vibration of springs supported downstream prism was measured close to the lock-in wind speed in smooth flow. To identify the aero-elastic parameters, such as Y1,  and Y2, the trace-to-resonance method was adopted with the decay-to-resonance rules. It is well contributed to build up the predicting model of the aerodynamic loadings with the measured results of the vibration of prism under the wake interference effects with these parameters. With the aero-elastic parameters we collected in the various experiments cases, an empirical predicting model with the neural network predicting technique were constructed in this study. It is found that more clear trend of aero-elastic responses will be arose from this empirical model.
Dynamic Characteristics of a Wood Frame Structure: (II) the Effect of Artificial Damage
Authors: Xing Hai Ling , Yao Dong Sheng , Xue Song Tao
Published: March 2013

A full-scale, three-storey wood frame structure had been tested in-situ to investigate the changes of dynamic properties due to artificial damage. Beams and braces of the test structure were removed, to simulate damage, and then reassembled, to simulate rehabilitation. Free vibration tests were performed during every stage of the tests. The natural frequencies and damping ratios were obtained using modal parameter identification technique based on the Hilbert-Huang Transform. It is shown that, when the structure is damaged or rehabilitated, the natural frequency changes in accord with the structural stiffness in general while the damping ratio varies irregularly.
Nonlinear Inelastic Buckling Behavior and Residual Strength of H-Section Steel Column
Authors: Yeshewawork Abebe Daniel , Choi Jae Hyouk
Published: March 2013

A nonlinear analytical approach for evaluating the inelastic buckling and residual strength of column member is presented in this study. A steel column member subjected to an axial compression load will shorten in the direction of load. If the load increased until the column buckles, the shortening will stop and the column will suddenly bend or deform laterally and may at the same time twist in a direction perpendicular to its longitudinal axis. However; before final buckling or collapse, steel column member has a tendency of plastic deformation. The issue has been much discussed along with the evaluation of plastic deformation capacity and restoring force of column members in the large deformation range following inelastic post-buckling. In order to predict the inelastic buckling behavior of the member, the load-deformation relationship needs to be identified in the whole process. To verify the accuracy of the nonlinear finite element analysis, compression test on an H-shaped steel column member was carried out and both inelastic deformation and the relationship between load-displacement curves were compared.
The Study on Bearing Capacity of Concrete-Filled Double Skin Steel Tubular Columns of Octagon Section under Axial Compression
Authors: Ge Qing Yun , Li Cai Mei , Yang Fu Lian
Published: March 2013

Based on unified strength theory solution of thickness cylinder, according to the introducing concrete strength reduction factor and equivalent restriction factor, this paper deduced the axial compressive bearing capacity formula of concrete-filled double skin steel tubular columns of octagon section. Compared the results of the paper with the experiment results，both coincide in good condition. The results show that the theoretical formula are correct and viable. The theoretical formula is expected to provide a theoretical foundation to the research of concrete-filled double skin steel tubular columns of octagon section.And it provides references for the engineering design.
Self- and Solute Diffusion, Interdiffusion and Thermal Vacancies in the System Iron-Aluminium
Authors: Mehrer Helmut , Luckabauer Martin , Sprengel Wolfgang
Published: March 2013

Starting from fundamental aspects of thermal vacancies and solid-state self-and solute diffusion, this paper reviews procedures for tracer-and interdiffusion studies and of the major techniques for vacancy studies by dilatometry and positron annihilation in metals. Equilibrium vacancy and diffusion studies performed on pure iron and aluminium are mentioned at first. We also comment some peculiarities of solute diffusion in aluminium. Positron annihilation and differential dilatometry studies for Fe-Al alloys with various compositions are summarized and new experimental studies by the authors are reported for vacancy migration in Fe61Al39. All these studies indicate a relatively high fraction of thermal vacancies with relatively low mobility in this type of iron-aluminides as compared to pure metals. Tracer diffusion of iron and of several substitutional solutes such as Co, Ni, Cr, Mn, Zn, and In in Fe-Al from the Münster laboratory are summarized. The diffusion studies of Fe-Al cover various alloy composition between Fe3Al and FeAl and several structures such as A2, B2 and D03. Interdiffusion coefficients obtained from diffusion couples between Fe-Al alloys are discussed together with Fe tracer diffusion data. The Darken-Manning equation is used to deduce Al diffusivities therefrom. The latter are hardly accessible to radiotracer experiments due to a lack of a suitable Al tracer. Diffusion of Al is slightly faster than diffusion of Fe indicating diffusion mechanisms with coupled jumps of Fe and Al atoms.
Magnetically Controlled Grain Boundary Migration and Microstructure Evolution in Zn
Authors: Molodov Dmitri A. , Günster Christoph , Gottstein Günter
Published: March 2013

The migration of planar grain boundaries induced by a magnetic field was measured in specially grown zinc bicrystals (99.995%). Particularly, symmetrical and asymmetrical <> tilt grain boundaries with rotation angles in the range between 60° and 90° were investigated. Boundary migration was measured in-situ in the temperature range between 330°C and 415°C and the absolute values of grain boundary mobility were obtained. The results revealed that grain boundary mobility essentially depends on the misorientation angle and the inclination of the boundary plane. An application of a magnetic field during the annealing of cold rolled (90%) Zn-1.1%Al sheet specimens substantially affected the texture and microstructure evolution. This effect is attributed to the additional magnetic driving force for grain growth arising due to the magnetic anisotropy of zinc.
Diffusion of Particles Adsorbed on a Patchwise Surface
Authors: Tarasenko Alexander
Published: March 2013

The diﬀusion of particles adsorbed on a patchwise surface with two non-equivalentsites is investigated in the framework of the lattice-gas model. The coverage dependencies of thecenter-of-mass and Fickian diﬀusion coeﬃcients are calculated for some representative valuesof the lateral interaction. We propose the analytical expressions for the diﬀusion coeﬃcients.We compare the theoretical dependencies with the numerical data obtained by the kineticMonte Carlo simulations. The good coincidence of the data obtained by the two quite diﬀerentmethods corroborates strongly the approach developed to describe the particle migration onsuch complex, heterogeneous lattices.
Fuel-Matrix Chemical Interaction between U-7wt.%Mo Alloy and Mg
Authors: Huang K. , Heinrich H. , Keiser D.D. , Sohn Yong Ho
Published: March 2013

A solid-to-solid, U-7wt.%Mo vs. Mg diffusion couple was assembled and annealed at 550°C for 96 hours. Themicrostructurein the interdiffusion zone and the development of concentration profiles were examined via scanning electron microscopy, transmission electron microscopy (TEM) and X-ray energy dispersive spectroscopy. A TEM specimen was prepared at the interface between U-7wt.%Mo andMgusing focused ion beam in-situ lift-out. The U-7wt.%Mo alloy was bonded well tothe Mg at the atomic scale, without any evidence of oxidation, cracks or pores.Despite the good bonding, very little or negligible interdiffusion was observed.This is consistent with the expectation based on negligible solubilities according to the equilibrium phase diagrams. Along with other desirableproperties, Mgis a potential inert matrix or barrier materialfor U-Mo fuel alloy systembeing developed forthe Reduced Enrichment for Research and Test Reactor (RERTR) program.
Diffusion Processes in Early Stages of Precipitation in Mg-Gd and Mg-Tb Alloys
Authors: Melikhova Oksana , Čížek Jakub , Hruška Petr , Vlach Martin , Smola Bohumil , Stulíková Ivana , Procházka Ivan
Published: March 2013

Early stages of precipitation were investigated in solution treated binary Mg-Tb and Mg-Gd alloys. The supersaturated solid solution of Gd (or Tb) in Mg was formed by fast quenching of the alloys from solution treatment temperature. Decomposition of the supersaturated solid solution and precipitation effects were investigated by positron lifetime spectroscopy combined with microhardness testing. During solution treatment at elevated temperature some thermal vacancies form pairs with solute atoms. In quenched samples free vacancies are quickly annealed out, while more stable vacancies bound to solute atoms remain in the sample and enhance the diffusivity of solutes. The hardness of solution treated Mg-Tb and Mg-Gd alloys aged at ambient temperature rises due to formation of small clusters of Tb and Gd atoms. Isochronal annealing of Mg-Tb and Mg-Gd alloys leads to precipitation of coherent β phase, semicoherent β phase and incoherent β phase particles. It was found that natural aging of Mg-Tb alloy at ambient temperature has beneficial effect on subsequent hardening by β phase particles formed during annealing.
Description of Whole Banana Drying through a Diffusion Model Using Numerical Solution via Generalized Coordinates
Authors: Silva e Silva C.M.D.P. , Pereira Silva Wilton , Gomes J.P. , Farias V.S.O. , Silva L.D. , Gama F.J.A.
Published: March 2013

Drying is a method of preservation widely used to prolong the post-harvest life of several agricultural products. In this work, experiments were accomplished involving drying of whole bananas, using hot air at temperature of 40.0 ºC and constant velocity of 1.5 m s-1. The mass loss in regular time intervals was measured using the gravimetric method. In order to describe the process, the liquid diffusion model was used, assuming variable volume and effective mass diffusivity [. Thus, the diffusion equation was numerically solved through the finite volume method, with a fully implicit formulation. Due to the geometry of the product, the diffusion equation was written in generalized coordinates, and then discretized, assuming boundary condition of the third kind [. To take advantage of the symmetry, bananas were considered as revolution solids, obtained by the rotation of an area in the plane (x,y) about the axis y. The area was obtained directly of the photography of a banana, which served to create a non-orthogonal structured grid with 32 x 40 control volumes. The thermo-physical parameters were obtained through an optimization algorithm, based on the inverse method. Once the thermo-physical parameters were known, the drying kinetics as well as the water distribution within the bananas in stipulated times were presented and analyzed. The statistical indicators enable to conclude the methodology proposed to describe whole banana drying presents good results.
Preparation of Ferromagnetic Manganese Doped Cobalt Ferrite-Silica Core Shell Nanoparticles for Possible Biological Application
Authors: Rostamzadehmansoor S. , Seyed Sadjadi Mirabdullah , Zare K. , Farhadyar Nazanin
Published: March 2013

Magnetic oxide nanoparticles with proper surface coatings are increasingly being evaluated for clinical applications such as hyperthermia, drug delivery, magnetic resonance imaging, transfection and cell/protein separations. In this work, we investigated synthesis, magnetic properties of silica coated metal ferrite, (CoFe2O4)/SiO2 and manganese doped cobalt ferrite nanoparticles (Mnx-Co1-xFe2O4 with x = 0.02, 0.04 and 0.06)/SiO2 for possible biomedical application. All the ferrites nanoparticles were prepared by co-precipitation method using FeCl3.6H2O, CoCl2.6H2O and MnCl2.2H2O as precursors, and were silica coated by the Stober process in directly ethanol. The composition, phase structure and morphology of the prepared core/shell cobalt ferrites nanostructures were characterized by powder X-ray diffraction (XRD), Fourier Transform infra-red spectra (FTIR), Field Emission Scanning Electron Microscopy and energy dispersive X-ray analysis (FESEM-EDAX). The results revealed that all the samples maintain the ferrite spinel structure. While, the cell parameters decrease monotonically by increase of Mn content indicating that the Mn ions are substituted into the lattice of CoFe2O4. The magnetic properties of the prepared samples were investigated at room temperature using Vibrating Sample Magnetometer (VSM). The results revealed a strong dependence of room temperature magnetic properties on (1) doping content, x; (2) particle size and ion distributions.
Resin Transfer Molding Process: A Numerical Investigation
Authors: Rodrigues Iran , Amico Sandro Campos , Souza Jeferson Avila , Ferreira Luz F. , Barcella R. , de Lima Antônio Gilson Barbosa
Published: March 2013

In the processing of high performance composite materials, the RTM process has been widely used by many sectors of the industry. This process consists in injecting a polymeric resin through a fibrous reinforcement arranged within a mold. In this sense, this study aims to simulate the rectilinear infiltration of pure resin and filled resin (40% CaCO3) in a mold with glass fiber preform, using the PAM-RTM commercial software. Numerical results of the filling time and fluid front flow position over time were assessed by comparison with the experimental data and a good accuracy was obtained.
On the Diffusion Profile at the Brazed Interface between Active Filler Metal and CVD Diamond Plates
Authors: Bagnato Osmar Roberto , Francisco Fernanda Regina , Corat Evaldo Jose , Moro Joao Roberto , Llopes Diego
Published: March 2013

Diamonds films have characteristics that are interesting for many optical applications, such as transparency to ultraviolet, visible and infrared light. These applications include use in detectors and windows in processes that involve high temperatures, microelectronics applications and wear-resistant components [. Polycrystalline diamond films can be made in the vapor phase at low-pressure, relatively low temperatures and in the form of auto-supported films, using the CVD process (Chemical Vapor Deposition) [. These films have a significant number of industrial applications, but often have problems with adhesion to metallic substrates. Diamond films can be deposited directly over some metals, but other techniques, such as brazing, can be used [.
Fluorescence Study of Ionic Intercalation/De-Intercalation in the Reaction-Diffusion Mediated Polymorphic Transition of a Class of Nanolayered Material
Authors: Rahbani Janane , Al-Ghoul Mazen
Published: March 2013

The mechanism of the intercalation/de-intercalation processes during the formation of α-Co (OH)2 and its conversion to β-Co (OH)2 is carefuly examined using a new non-invasive technique in a gel matrix. The incorporation of rhodamine molecules inside the interlayer gallery of α samples allows us to monitor the variation of its fluorescence intensity throughout different stages of the reactions. We show after calculating the corresponding activation energies that the formation/transformation reactions exhibit different dynamics depending on the nature of intercalated anions. Moreover, the morphological changes that are revealed from scanning electron micrographs suggest the occurence of an Ostawald ripening mechanism in which perfect and stable crystals are produced at the expense of smaller ones.