bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of Universal Detection System for Automobile Combination Dashboard
Authors: Yuan Hui Juan , Liu Wei , Hu Wei , Sun Yong Quan
Published: March 2013

The detection of automotive combination dashboard is usually implemented by adopting the specific detection system matched with models, and automotive combination dashboard of different models requires different detection systems. A universal automatic detection system is designed in this paper, which can detect different kinds and models of automotive combination dashboard. First, standard detection signal generated by the electronic control unit is added to every corresponding position of dashboard, second, cameras film the corresponding images of dashboard in the standard signal excitation, last, the image is sent to the host computer for image processing to get output data of dashboard. This system detects results of automotive combination dashboard with the maximum relative error less than 2.5%, which meets the specified accuracy requirements in the automotive industrial standard QC/T727-2007 “Instruments for Motor Vehicles and Motorcycles”
Research Switched Reluctance Motor Drive (SRD) Based on Fuzzy Sliding Mode Control
Authors: Zhou Yong Qin , Liu Rui , Cui Yan Guang , Wang Xu Dong
Published: March 2013

For the shortcomings of the torque ripple of switched reluctance motor (SRM), this paper presents a strategy of controlling switched reluctance motor drive (SRD) with fuzzy sliding mode controller. The speed loop uses the conventional PI regulator, and the current loop adopts the fuzzy sliding mode controller which takes the current deviation as switching function and combines with fuzzy reasoning to determine the value of switching gain. The fuzzy sliding mode controller will realize the precise current control and enhance the stability of the system. The simulation results show that the system can suppress the torque ripple effectively and realize high-performance SRD control.
The Application of Fault Diagnosis Based on EMD and Real Modulation Zoom Method
Authors: Xiang Jing Zhong , Ge Fu Peng , Sun Han , Shi Xian Jiang
Published: March 2013

It is first to make Empirical Mode Decomposition (EMD) and achieve Hilbert-Hung transform (HHT) of envelope spectrum after Hilbert transformation, which can resolve the cross fault existing in Hilbert transformation is utilized merely. However, it can’t improve the resolution of envelope spectrum, which doesn’t adapt the characteristic of high resonant frequency of rolling bearing and low fault frequency. The paper utilizing the principle of real modulation shift frequency moves the EMD decomposition components of high frequency section to low frequency section and makes analysis of envelope spectrum after Hilbert transformation, which resolves the problem of low frequency resolution of pure HHT.
Preparation of High Insulating HDPE Optical Cable Sheath at Lower Cost with Doping Nano-Particles
Authors: Zhang Ji Peng , Tang Hui , Hao Shan Shan
Published: March 2013

To reduce the cost of HDPE optical cable sheath, we selected HDPE as matrix materials, inorganic nanometer particles (CaCO3, SiO2) as modifier, prepared the modified HDPE optical cable sheath by mechanical blending method. The combination of CaCO3 particles with HDPE matrix was improved by titanate doped, which was able to facilitate the homogeneous dispersion of CaCO3 particles inside HDPE. To modify the optical cable sheath and reduce the product cost, the disparity of the inorganic nano-particle was analyzed, and the ratio of raw material and mixing technology were also improved. The experimental results indicated that: the sheathing compound with insulating characteristic as well as all technical indexes that reached its national standard, especially the toughening effect of the CaCO3, could be produced when CaCO3 content reached 7.5% and the volume resistivity was 104 times higher than the national standard. The mechanical modification of CaCO3 was better than SiO2.
Interval Element-Free Method for a Bi-Material Cantilever Beam
Authors: Wen Yong , Wang Shu Fan , Yan Zhao Jie , Liu Na
Published: March 2013

The interval element-free Galerkin method (IEFGM) is proposed to analyze a bi-material cantilever beam, which is an interfacial mechanics problem including uncertain parameters. Interval method could be applied to study the influences of the uncertain parameters on structural responses. The IEFGM could be used to approximate the displacement fields without depending on meshes. Combining these two methods, the interval equilibrium equations are derived, and a method of dealing with the discontinuities on the interface is introduced.
Preparation and Characterization of Aluminum Nitride Nano-Wire
Authors: Sun Yan Long , Liang Yin Chan , Zhi Ming Le , Zeng Zhao Fen , Dong Li Min
Published: March 2013

Aluminum nitride (AlN) nano-wire was synthesized by double decomposition with AlCl3 and NaN3 in stainless steel cauldron without solvent and using Mg as promoter. The effect of reaction temperature, holding time and promoter to the structure, surface morphology and particle size are analyzed. The synthesized AlN was characterized using X-ray diffraction (XRD) and scanning electronic microscopy (SEM). A series of electron microscopy characterization results show that the optimum reaction conditions are as follows: reaction temperature is 450°C and holding time is 8h. The average diameter of AlN nano-wire is 100nm.
Extraction Process of Selenium Polysaccharide in Hedgehog Fungus and Determination Analysis of Chemical Components
Authors: Ding Jun
Published: March 2013

The target of the paper is to study the method of extracting polysaccharide containing selenium from Hericium erinaceus by using the method of water extracting-alcohol precipitating. The objective is to determine the best technological condition of the extraction process of selenium polysaccharide in hedgehog fungus. Method: applying an atomic absorption spectrophotometry to detect the content of inorganic element in selenium-rich hedgehog fungus; employing the 2, 3-diaminonaphthalene fluorescence spectrocolorimetry to detect the selenium content in the selenium-rich hedgehog fungus; using phenol-sulfate method to detect crude polysaccharide. Conclusion: we have presented three simple detecting methods with advantages of low sampling volume, little interference to analyze and reliable results; therefore, the methods are worthy of popularizing and using.
GIS Application in Analysis of Flood Inundation
Authors: Liu Ya Qiu , Zhang Chen Hui , Zhang Xiao Peng
Published: March 2013

Flood disaster affects the development of our national economy seriously and made people’s life and property in danger. It also destroyed our ecological environment. In this paper, a model which is based on the geographic information system (GIS) has been introduced with the flood submerging range and submerging algorithm. Experimental results with Xi-tiao-xi area flood region using of digital elevation model (DEM), provides that it is possible to make a rapid flood damage assessment and scientific flood control decision service. The simulation performance is accurate and rapid.
Foundation Reinforcement Design for Sugar-Making Workshop of Hailun Sugar Plant
Authors: Chen Yuan Jing
Published: March 2013

The problem to be firstly considered is whether the base of the existing factory meets requirements or not for the renovation and reinforcement of the existing industrial building. Starting from this point of view, the solutions and suggestions were put forward for the problems met in schemes, computation, structure and construction in the procedure of base reinforcement design, as the reference for the designers of similar projects.
Health Office Chair Design Based on Ergonomics
Authors: Yang Hai Bo , Sang Shu Guang , Feng Yu Tao
Published: March 2013

Starting from human design perspective of the product and using ergonomics knowledge, measurement method and model method are adapted to analyze harmonious relations between people in the sedentary state and office chairs in various parts. The research aims at how to correctly apply the theory of ergonomics in the design of new product development to ensure that the technical problems related to design fitness. And for the “Chair family ”--- the sedentary population, the user-friendly design elements of health office chairs, methods and performance evaluation are studied and summarized as well.
Numerical Investigation on the Reticulated Domes Subjected to the Multi-Point Impact
Authors: Lin Li , Fan Feng , Zhi Xu Dong
Published: March 2013

In the present paper, FE model of the single-layer Kiewitt-8 reticulated domes with a span of 60m was built with using of ANSYS/AUTODYN. The dynamic response of the reticulated domes against the multi-point impact was investigated, where a special impactor was involved. Based on the simulation results, four damage modes were concluded，which are local damage, global collapse, local damage with punching plug, punching plug respectively. It was indicated that the initial kinetic energy of the impactor have a close correlation with the damage mode. Furthermore, the characteristics of dynamic response for each damage mode were shown.
Comparison of Temperature Field of French Windows Building with Different Types of Floor Radiant System
Authors: Liu Zhi Long , Wang Fang , Niu Lian Jing , Li Chen Xia , Fu Guo Min
Published: March 2013

In modern buildings, especially the large-scale ones, the use of French windows becomes more and more popular. In these buildings, compare with the traditional heat sink, the floor radiant system has a wide range of applications because the temperature field of it is more uniform and it is much easier to arrangement. In this paper, by the way of numerical simulation, the ground surface temperature field and indoor air temperature field of three different types of floor radiant system are compared using the CFD software FLUENT. At last, the parallel type can be the best choice in the French windows buildings for the temperature field of it is high but not too high to make people feel uncomfortable.
The Research of Three Significant Changes Resulted from Industrialization in the Development of Architecture
Authors: Chen Xing , Yang Hao Zhong
Published: March 2013

Architecture has changed dramatically along with the development of industrialization. In contrast to some of the more traditional methods of the construction industry organized predominantly along craft lines, architecture can now be the industrial product of components made in a factory [1]. It is the big change in the process of designing, manufacturing and constructing. The three changes make architecture a kind of industrial product, and not only an art work or something else. What details about these changes involved, why these changes exist and how these changes influence architecture are all main things to study. Through analyzing some particular buildings, these problems were made clear, and we found what is good or bad in these changes for architecture. On the basis of the research, we could get a good answer to the direction of the development of architecture in form, design, manufacture style and constructing process.
Nonlinear Module Control of Maglev Levitation System Based on Feedback Linearization
Authors: Li Jin Hui , Li Jie
Published: March 2013

This study develops an electromagnet-air spring-vehicle coupled model of the actively controlled, magnetically levitated system. Based on the coupled model, the nonlinear module controller based on the feedback linearization is adopted. The experiment verification on CMS04 low speed maglev vehicle is carried out; the results show that the tracking performance and decoupling ability of proposed controller is satisfied.
Research of Micromotion Reading Subdivision Method
Authors: Wang Jin Song , Shi Yan , An Zhi Yong , Liu Ming
Published: March 2013

According to the present situation and development of testing variational momentum of the zero position for optical telescopic aiming system.A new measurement mechanism is designed and a new micromotion reading subdivision method is putted forward. Based of these, the main structure of micromotion reading system is described and the errors are analyzed and calculated. The experimented results show that the actual maximum measurement of this mechanism is 10.8"and the resolution is 2.16".
Simulation of Gas-Solid Two-Phase Flow Using LES-SOM Model
Authors: Chen Ju Hui , Hu Ting , Li Jiu Ru
Published: March 2013

Flow behavior of gas and particles is predicted by the large eddy simulation of gas-second order moment of solid model (LES-SOM model) in the simulation of flow behavior in CFB. This study shows that the simulated solid volume fractions and velocity along height using a two-dimensional model are in agreement with experiments. The second-order moments of particles are computed.
Research on Control Strategy of Oil Film Stiffness Control System of Hydrostatic Center Frame
Authors: Wang Zhong Wen , Duan Rui Zhen , Xu Wan Li , Tao Fu Chun , Xu Xiao Qiu
Published: March 2013

Design a new type of electro-hydraulic servo control system of oil film in hydrostatic center frame, regulate and control oil film thickness adopting various controllable oil chambers, build mathematical models of control system and carry on system model identification and verification. Propose a control strategy about fuzzy sliding model variable structure, and it is applied in the model achieved by identification, adopt the method of fuzzy control system approximating equivalent control and design switching controller based on fuzzy control gain dynamic regulation, which could inhabit buffeting existing in sliding model variable structure control. Simulation results show that the controller can’t only effectively inhabit buffeting and reduce steady-state error, but also has strong robustness for structure parameter uncertainty.
Using Fuzzy Switching to Achieve the Smooth Switching of Force and Position
Authors: Gao Bing Wei , Shao Jun Peng , Han Gui Hua , Sun Gui Tao , Yang Xiao Dong , Wu Di
Published: March 2013

In order to achieve the switching function of the force and position, the force control is executed when the hydraulic cylinder contacts with the mechanical objects, the position control is executed when the hydraulic cylinder is far away from the mechanical objects. This paper respectively established force control model and position control model. The position control adopts the PID algorithm and the force control adopts the fuzzy algorithm. In order to solve the jump and jitter of the parameters when force-position switching, this paper puts forward a fuzzy switching adaptive control strategy. Fuzzy switching ensures the smooth transition of the two control models, the results of simulations show that fuzzy switching not only ensures the system’s rapidity but also shows excellent robustness against variations of system parameters and external disturbances.
Simulation Analysis of Friction Nonlinear for NC Servo System
Authors: Dong Yu Hong , Tian Su Ling
Published: March 2013

Friction nonlinear is common in mechatronics system. It can decrease dynamic tracking accuracy, rapidity and relative stability of the system. For NC servo system as an example the simulation analysis is carried out for friction nonlinear. Analyzing friction torque, the difference between dynamic and static friction torques have effects on the system performances. The simulation results illustrate that friction nonlinear mainly affects lower speed track performance of servo system lower. With rotation velocity instruction lower dynamic tracking accuracy and relative stability of servo system more decreasing, the response lag more severity. In the condition of rotation velocity instruction invariable, the bigger the difference between dynamic and static friction torques the worse relative stability and response lag of the system. The paper’s study has the reference value for design and improving lower speed performances of servo system.
Intelligent Campus Emergency Preparedness Managing Platform System
Authors: She Yan , Ben Xian Ye , Wang Ke Jun , Wang Ze
Published: March 2013

Considering the feasibility of the application of GIS technology and multimedia technology in campus emergency preparedness managing platform system, this paper discusses the overall design for visual campus emergency preparedness management system, where the principles of prevention and treatment for campus public emergency and this emergency preparedness visualization management system works are proposed. Then, various multimedia animation preparedness is realized by using Flash soft. By the way of analyzing various data of GIS, using professional software tool of GIS-MapInfo, taking Scilab as platform, we realize the functions of the intelligent electronic map design for HEU campus. This platform can enable visualized query and data searching, such as Eagle eye location, target finding, the shortest path searching, network communication and preparedness videos playing.
Analysis of Fiberglass Winding Angle on Natural Frequency of Free Vibration of Cylindrical Shell with Asymmetric Boundary Conditions
Authors: Wang Zhi Wei , Wu Bo , Wang Yan Fu , Bosiakov S.M.
Published: March 2013

In order to obtain approximate solution of natural frequencies for the free vibration of anisotropic circular cylindrical shells made of GFRP (glass fiber-reinforced plastic) with asymmetric boundary conditions, Love’s theory and energy method are used. Computation results show that the fundamental natural frequency comes from different vibration modes while the winding angle varies, the effect of number of axial half waves is stronger than number of circumferential waves on natural frequency of free vibration of anisotropic circular cylindrical shell. The effect of shell’s geometrical parameters is also investigated on natural frequencies.
Automated Essay Scoring: A Comparative Study
Authors: Yao Xue Mei
Published: March 2013

Automated essay scoring has been the focus of a cross-disciplinary study of computer science and English instruction. In this study, an experiment was conducted to testify the validity and reliability of E-grading Device and to check out whether the holistic score generated from combining computer and human score is a better solution to automated essay scoring system. The conclusion is that e-evaluation systems are valid and reliable basically, and e-evaluation and human evaluation should be combined together to generate holistic scores.
Reliability Prediction of RV Reducer Based on Fault Tree and Monte-Carlo Simulation
Authors: Sun Y.G. , Yu G.B. , Zhang J. , Wang F. , Sun Y.Q. , Chen J.H.
Published: March 2013

Wavelet de-nosing method for complex signal is put forward in this paper. The time resolution and frequency resolution are changed as wavelet transform for signal analysis. It uses high-frequency resolution and low time resolution in low frequency analysis, and uses low-frequency resolution and high time resolution in high frequency analysis. So it fit the uncertainty principle and realize the signal time domain and in frequency domain at the same time. In this paper, the configuration of RV reducer is briefly introduced, and its fault tree is constructed taking the fault of “Output shaft can not transfer torque” as top event through illuminating potential system unit failures and analyze the effect on whole system. And then system reliability qualitative and quantitative analysis are conducted. The fault tree qualitative analysis is operated based on the minimal cut set. Followed establishing simulation model of RV reducer, system life time is obtained using Monte-Carlo random sampling method. Furthermore, system life distribution is deduced, and point and confidence interval of distribution parameters and reliability characters are given by Maximum Likelihood Estimate. Finally, simulation experiment and results analysis are given to show the effectiveness of this method.
Study on Modeling Design of CNC Machine Tool Based on Ergonomics
Authors: Lu Xiao Meng
Published: March 2013

Based on the study of ergonomics, this paper summarizes morphological characteristics of computer numerical control machine tool modeling, and according to the work functions and operation characteristics, it gives an analysis of the principles and requirements of computer numerical control machine tool modeling design and ergonomics, which will help broaden our thoughts in designing more vivid, lively and rapid new computer numerical control machine tool modeling.
Numerical Analysis of Fire Behavior of Reinforced Concrete Frame Structure
Authors: Bi Ran , Liu Yong Jun , Yan Yu Min , Yao Li Hong
Published: March 2013

Analysis the fire behavior of the reinforced concrete frame structure from three aspects: the fire scene simulation, the temperature distribution and the deformation calculation of structure. Applying the actual temperature curves based on fire simulation software FDS to finite element analysis software ANSYS, get the temperature distribution and the deformation of structure under fire. Results show that structure will be destroyed because of the beams under fire are reaching the fire resistance, and the calculation results can meet the requirement of specification. Finally, the practical application shows the feasibility of getting the temperature-time curves with FDS instead of the international standard temperature-time curves for fire process analysis.
Stress Impact Analysis of Steel Frame with Different Beam-Column Connection Mode
Authors: Wang Gang
Published: March 2013

This paper uses the SAP2000 to establish different beam column connections of steel frame structure finite element model, comparative analysis of the beam column for the rigid connection, hinged, semi-rigid connections of steel frame structure, the dynamic characteristics of structure displacement and internal force influence. At the same time, the dynamic time-history analysis method for structural displacement supplementary checking, analysis of structural response to seismic wave degree．The results showed that：compared with rigid, the structure of semi-rigid connections to the larger natural period，and with the rotation stiffness decreases vibration period increases; Semi-rigid steel frame connection to reduce the resistance to push the layer stiffness，making the structure of the horizontal displacement increased．
Shaking Table Test on Seismic Response of Isolated Bridge
Authors: Yan Xiao Yu , Wang Li Hui , Du Xiu Li
Published: March 2013

In order to investigate isolation effectiveness on seismic performance of the continuous rigid frame bridge, shaking table test with nine sub-tables on 1/10 scaled reinforced concrete rigid frame bridge specimen was performed. The experimental results demonstrate that isolation devices provide flexibility to transform natural period of the scaled model, and additional it can improve the ability of energy dissipation when lead is used. The initial first frequency is 8.17Hz for plate-type rubber bearing and 9.12Hz for leading rubber bearing. The plate rubber bearing and lead-rubber bearing are quite sensitive to seismic wave frequency. The use of various isolation devices affects response of the bridge model. The results show that the more difference in the isolation devices, the more difference in response. Moreover, isolation effect of lead-rubber bearing show obviously more advantage than the one of plate-type rubber bearing, especially in controlling responses of the bridge during major earthquakes.
The Detection, Identification and Structural Analysis of the Steel Structure Engineering
Authors: Chen Shao Hui , Wu Han , Peng Xiao Chuang
Published: March 2013

This paper is aimed to a steel structure needed to add layer of this situation, the structure of the overall appraisal. On the basis of testing application SAP2000 and PKPM respectively on the existing structure and add layer structure of the theory analysis and conclusion: the existing structure various indexes meet the standard, except member slenderness ratio; Add layer structure of the torsion effect is abate, overall stability problems etc. The appraisal and analysis of project will be for the future similar project to provide some reference.
Study on Internal Force Redistribution Caused by Uneven Settlement of Frame Structure
Authors: Liu Xu Jie , Yan Bin
Published: March 2013

This paper was based on the frame structure model with fixed support, and put forward five kinds of condition caused by uneven settlement. ANSYS was used to analyze the stress characteristics of frame structure. Through the comparative analysis of five kinds of condition, change law of the structural internal force is found.
Experimental Study of CFRP Confined RC Rectangular Hollow Section Bridge Piers
Authors: Dong Zhen Hua , Han Qiang , Du Xiu Li , Wang Pi Guang
Published: March 2013

To investigate the seismic performance of FRP strengthened RC hollow section bridge piers under multi-dimensional earthquake excitation, the pseudo-static test was carried out to RC rectangular hollow section as-built and CFRP confined bridge piers under constant axial compression force and bidirectional horizontal repeated load. The failure characteristics, lateral force-deformation curves and ductility of specimens were analyzed. The experimental result shows that CFRP constraining may change the failure mode of hollow section bridge piers, and significantly improve the deformation ductility, plastic deformation, however, it is less contribution to horizontal force of specimens with less wall-thickness.
The Forecast Model to Carbonation Depth of Prestressed Track Beam of Light Rail
Authors: Chen Ming Zheng , Liu Xian Feng , Huang Lin Qing
Published: March 2013

Though the introduction of light rail transit status and the reinforcement of prestressed track beams, this paper explored the carbonation mechanism of prestressed track beams, and analysised the main influencing factors of prestressed track beams. Based on concrete carbonation depth forecasting model, this paper analysised the carbonation law of of prestressed track beams in Chongqing, and proposed the durability design measures to prestressed track beams.
Damage Detection in Beam-Type Structures Using Fractal Dimension Trajectory of Rotated Higher Vibration Modes
Authors: Bai Run Bo , Xu Zong Mei , Qiu Xiu Mei
Published: March 2013

Damage-induced local response is probably easy to be captured by the higher modes of the structures, especially for the small defects. The aim of this paper is to overcome the inherent deficiency of fractal dimension to identify crack when implemented to higher mode shapes. The proposed approach reconstructs the higher mode shape through rotation transformation, and then the fractal dimension analysis is implemented on this new mode shape to yield a fractal dimension trajectory. The location of the crack can be determined by the sudden peaks at the fractal dimension trajectory. The applicability and effectiveness of the proposed method is validated by using numerical simulations on damage identification of a cracked cantilever beam.
The Static Impact Analysis of a Blast Furnace Equipment Load on the Structure in Taiyuan
Authors: Zhang Wan
Published: March 2013

There are a variety of forms of industrial construction equipment load .The structural design engineers replace equipment load by equivalent load to analyze structure while it is impossible to reflect the combination of equipment and structure or synthetically dynamic characteristics exactly. This article use SAP2000 to provide three kinds of load input modes for blast furnace equipment in chemical buildings, and that blast furnace equipment should be involved in the overall structure of the modeling analysis in order to obtain accurate load information.
Mechanical Behavior of Steel Arch Bridge with Outward Inclined Ribs
Authors: Li Ding Shi , Su Qing Tian , Liu Yuan Wei
Published: March 2013

Steel tied arch bridge with outward rib was adopted in Aixihu bridge in Nanchang city, in which steel girder width was 73 m. Outstanding features, such as large ratio of width to length, outward inclined ribs, four groups arrangement of spatial suspender existed in this bridge. Beam-column finite element model (FEM) and shell-beam FEM for the arch bridge are established respectively. The mechanical behaviors of the arch ribs and the girder analyzed by two different models are compared. The calculation results show that both beam-column FEM and shell-beam FEM can be used in the analyzing the mechanical behavior of arch ribs, while for the wide girder mechanical character analysis should not depend on beam-column FEM but shell-beam FEM.
The Research for Cylinder Pressure and Penetration Method in Comprehensive Testing Mortar Strength
Authors: Peng Xiao Chuang , Chen Shao Hui
Published: March 2013

This paper briefly introduced the cylinder pressure - injection synthesis method which is detection masonry structure mortar strength technology principle, the technology based on the mathematical statistics method for data correction processing, and it combines the advantages between cylinder pressure method and penetration method ,and this method and more accurate and reliable than a single detection technique.
Mechanical Performance of Timber Beams Reinforced by FRP Sheets
Authors: Zhu Yan Mei , Li Lang , Hou Min , Wang Qing Yuan
Published: March 2013

In order to improve the mechanical performance of timber beams, five rectangular-section beams were used in flexural test and ten for shearing. The effects of FRP types i.e. CFRP, BFRP and AFRP, layers of FRP sheets and the way FRP sheets pasted were studied. The failure pattern, load-deflection curve, strain distribution and ultimate load capacity of the specimens were analyzed. The results indicate that the ultimate load carrying capacity of beams were increased by 15.4% to 55.1% varyingly with the reinforcement of FRP, besides, the stiffness and ductility were improved also. The improvements were lower in the specimens with material defects such as the existence of knags and shrink cracks. It’s more effective to paste the FRP sheets slantingly with the angle of 45° than vertically. However, the effect on the initial stiffness is not distinct whether reinforced or not. The analysis of strain and stress distribution manifests that the plane cross-section assumption is efficient in design and calculation of FRP reinforced timber beam.
The Effect of Interfacial Cracks on the Concrete Chloride Diffusion Coefficient Considering Aggregate Shape
Authors: Peng Guo Jun , Chen Chen Jie
Published: March 2013

Considering the concrete as a three-phase composite material composed of aggregate, interface and cement matrix, an octagon unit cell is constructed based on ellipse, and the numerical solution of concrete chloride diffusion coefficient considering the aggregate shape is obtained using the finite element method. The validity of the proposed algorithm is preliminary verified after compared with the available test results, and the effect of interfacial crack opening angle and aggregate shape on the concrete chloride diffusion coefficient is quantitatively evaluated. Through numerical calculation, it is found that the chloride diffusion coefficient of concrete increases with the increase of interfacial crack opening angle and decreases with the increase of aggregate shape coefficient.
Finite Element Analysis of the Precast Shear Walls
Authors: Liu Yun Lin , Yin Wan Yun , Ling Ru , Ding Ke Wei , Jin Ren Cai , Liu Shou Chen
Published: March 2013

To reduce the construction cost of the domestic promotion of the new prefabricated concrete shear wall structure system which is promoted in our country. To analyze the factors which can affect the load-carrying capacity and seismic performance of shear wall, including the axial compression ratio, the concrete strength, the reinforcement ratio and some other factors. Among all these factors, the axial compression ratio is the main factor influencing the seismic performance and the section ductility [1]. This paper adopts the ANSYS finite element analysis program, operating a nonlinear analysis on the performance of the precast shear wall when it is with one-way loading, studying the axial compression ratio's effect on the bearing capacity and deformability of the precast shear wall. According to the finite element analysis, when the axial compression ratio is between 0.2 to 0.4 and as it rises, the specimen's bearing capacity and stiffness will increases while deformability and ductility will decrease. Through the finite element analysis, we can provide reliable theory basis for the performance of the precast shear wall when it is with one-way loading.
Study on the Strength Properties and Failure Mode of Recycled Sludge Lightweight Soil
Authors: Wang Guo Cai , Sha Ling , Jin Fei Li
Published: March 2013

Lightweight technology is to transform the discarded materials, such as dredged silt, construction waste soil, waste foam plastics, industrial waste fly ash, waste gypsum, etc., into lightweight soil. This kind of soil has been utilized comprehensively, which can produce good economic benefit, environmental and social benefits. In order to further investigate the properties of mixed lightweight soil, this paper uses indoor test method to study the recycled sludge lightweight soil samples prepared from the construction waste soil by mixing with EPS particles and cement according to certain mass/volume ratio and cured in standard curing conditions. The strength properties and failure mode are analyzed using the direct shear test and unconfined compressive strength test, and the effect of curing period, cement content, EPS particle fraction, etc., on the strength and failure mode is analyzed.
Anisotropy Gas Reservoir Drainage Radius and Quantitative Well Interference Study
Authors: Gao Zheng Long , Fan Hong Fu , Gao Zhi Bin
Published: March 2013

Unstable productivity analysis method was used to obtain the equivalent radius of 77 wells and the result shows that the equivalent radius ranges from 30 to 970m with an average value of 230m in McKittrick Hills. The difference range of the radius is mainly caused by varying formation properties, gas saturation, production time, etc. Permeability anisotropy changes the drainage from round to ellipse. The major axis and the minor axis of the ellipse are determined by the ratio of major and minor permeability. Current pressure distribution was obtained and was found to be consistent with the modified drainage results, which demonstrates that the unstable productivity analysis method is applicable in the study of gas well drainage radius. An interference well and an observation well’s model was constructed to study well interference quantitatively. When the well spacing is larger than 750m, the productivity will be reduced by 20%. The production rate of interference well is more sensitive to the cumulative production of observation well, when the production rate of interference well is below 16.8×104m3/d.
Research and Applications of a Plane Embedded Combined Element Model Considering Bond and Slip
Authors: Wang Ji Wei , Qiao Qin Qin , Leng Fei
Published: March 2013

It is one of the most important issues for finite element analysis of lining structures that how to describe anchor rod reasonably and effectively and simulate the interaction between rod and concrete or rock. Virtual nodes are constructed in concrete/rock element at the ends of anchor rod and bond-slip element is set between virtual nodes and beam element which describes anchor rod. An embedded combined element with bond slip and shear deformation is established through the transformation of nodal force at nodes of bond-slip element to those of concrete/rock element via shape functions. The element is convenient for meshing element because the location and direction of anchor rod are not necessary to be considered. Meanwhile, the element has the advantage of low computing cost. Finally, the validity and efficiency are verified by numerical examples.
Cyclic Bending Response of Single- and Polycrystalline Thin Films: Two Dimensional Discrete Dislocation Dynamics
Authors: Fan Hai Dong , Wang Qing Yuan , Kashif Khan Muhammad
Published: March 2013

The bending behavior of single- and polycrystalline thin films is modeled by two-dimensional discrete dislocation dynamics (DDD) to study the cyclic bending response. In the polycrystalline films, grain boundaries (GBs) are simulated with a penetrable dislocation-GB interaction model. Our results reveal that the single- and polycrystalline thin films under pure bending exhibit strong Bauschinger effect but no cyclic hardening or softening. Furthermore, the uploading response of each cycle can be divided into three stages, which are associated with the glide, annihilation and nucleation of dislocations, respectively.
Analysis of Nonlinear Dynamic for Piles under Earthquake Loading
Authors: Lv Jian Gen , Qiu Jian Hui
Published: March 2013

The nonlinear dynamic response of piles in uniform foundation under earthquake loading is investigated. Based on the established nonlinear equations of motion of piles under earthquake loading, the approximate solution of the pile for the case of the resonance is obtained by the method of multiple scales. The effects of major parameters on seismic force are studied, such as, frequency ratio, shear wave velocity, soil thickness. And the effects of the major parameters on the frequency response curves of the pile in single layer soil are studied. Comparing with the non-resonant response of the pile, the effect of the resonance on the actual dynamic response is analyzed. The results shows that shear wave velocity and soil thickness have significant effect on the seismic force in soft clay, which have little effect on the seismic force in the other soil layers; soil thickness has the most important influence on the nonlinear dynamic response of pile and it is followed by the earthquake coefficient, the shear wave velocity in the effects.
Cyclic Behaviour of GFRP and Lateral Ties Confined Polyolefin Fibre Reinforced Concrete under Axial Repeated Compression
Authors: Palanivel S. , Sekar M.
Published: March 2013

Confinement by fiber reinforced polymer (FRP) wraps can significantly enhance strength and ductility of concrete. Although various models exist for envelope curves of concrete confined by transverse reinforcement and FRP, only a few simple models represent the hysteretic behavior of the confined concrete; therefore, development of stress–strain model of unloading and reloading paths for confined concrete is needed. In this paper, an experimental and numerical investigation for describing the cyclic stress–strain behavior of lateral ties and FRP confined polyolefin fibre reinforced concrete (FRPCFRC) prisms under repeated axial compressive loading is presented. The study focuses on the effect of repeated unloading and reloading cycles on confined concrete prisms. The combined effect of spacing of lateral ties, FRP wraps and volume fraction of polyolefin fibres was studied both experimentally and numerically from the point of deformability characteristics of concrete under repeated loading as loading, unloading and reloading.The envelope curve is derived from the results of uniaxial, monotonic, compression loading tests on specimens. It explicitly accounts for the effects of lateral tie spacing of 145mm spacing and 75mm spacing, single layer of woven roving(GFRP) and polyolefin fibres of volume fractions 0.7% and 1.2% on concrete prisms of size 150 ×150 ×300 mm were investigated. The behaviour was also simulated in finite element numerical model in ANSYS software, with a view to analyzing FRPCFRC prisms under repeated loading. This analysis accounts for energy dissipation through hysteretic behavior, stiffness degradation as damage progresses, and degree of confinement. It was observed from hysteretic behavior that for increased confinement by FRP wraps and addition of polyolefin fibres the degradation of strength and stiffness reduces significantly.
Numerical Analysis of Composite Soil Nailing Retaining Wall under Earthquake
Authors: Ma Tian Zhong , Zhu Yan Peng , Meng De Ju
Published: March 2013

The seismic response of slope supported by composite soil nailing is analyzed by using finite element software ADNIA, in which the EL-Centro wave is selected as input earthquake wave.The analytical contents include the displacement and acceleration of supporting slope, as well as the time history responses of the axial forces of anchors. In the establishment of finite element model, the interaction between soil body and supporting structure is considered. The elastic-plastic M-C model with nonlinear static and dynamic behavior is used to simulate the soil body, and the dual linear strengthen model is adopted to simulate the supporting structure, then the interaction between soil body and supporting structure is simulated with contact element. The results show that the composite soil nailing slope supporting structure has better seismic performance than the general soil nailing slope supporting structure. The maximum horizontal displacement of the latter occurs at the slope top, but that of the former occurs at the slope upper. Especially after the imposition of the prestress, the slope displacement under earthquake reduces significantly, and the axial forces of anchors under earthquake enlarge significantly. Moreover, the axial forces of anchors reach maximum values near the slipping surface. The displacement and the acceleration of slope increase along the slope height. The conclusions obtained provide basis for the seismic design of permanent supporting slope and reference for similar projects.
A Developed Strength Model for FRP Confined Circular Concrete Columns Based on a Most Updated and Comprehensive Test Database
Authors: Zhou Ying Wu , Sui Li Li , Xing Feng , Wu Ling Yi
Published: March 2013

This paper develops a new advanced strength model for circular columns retrofitted with fiber reinforced polymer (FRP) based on a newly collected test database which is so far the most updated and comprehensive one and has contained more than 800 axial compression test results of FRP confined circular concrete columns. This paper first reviews some existing design-oriented strength models and then provides an in-depth comparison between experimental test results and models predictions. The comparison results indicated that more or less deficiency exists when these models were extended to predict the confined strengths of a much larger amount of columns than that when they were derived, directly resulting in deteriorations of the prediction accuracy. These conclusions exactly reflect the necessity and significance of developing a new advanced confinement strength model in the paper.
Vertical Motion Inputs for Seismic Analysis of Large Span Bridge
Authors: Tao Zheng Ru , Tao Xia Xin
Published: March 2013

In seismic analysis of large span bridge, inconsistent ground motions in three directions, lengthwise, lateral and vertical are required to input at the base of each of the two main girder piers. In order to adopt synthesized motion field for the inputs, a simple way to prepare the vertical motion is introduced for improvisation at this moment in this paper, since the synthesis in general consists of two parts, the low frequency ground motion calculated by a numerical method, like FEM, and the high frequency motion synthesized by random approach, and the result of the former is in three dimensional, while that of the latter has just horizontal component. The vertical acceleration time histories proposed in the paper show the way is available.
Slope Stability Analysis of Elastic Limit Equilibrium Method
Authors: Kuang Lin , Lv Ai Zhong , Zhou Yu
Published: March 2013

Based on finite element analysis software ANSYS, slope stability analysis is carried out by Elastic limiting equilibrium method proposed in this paper. A series of sliding surface of the slope can be assumed firstly, and then stress field along the sliding surface is analyzed as the slope is in elastic state. The normal and tangential stresses along each sliding surface can be obtained, respectively. Then the safety factor for each slip surface can be calculated, the slip surface which the safety factor is smallest is the most dangerous sliding surface. This method is different from the previous limit equilibrium method. For the previous limit equilibrium method, the normal and tangential stresses along the sliding surface are calculated based on many assumptions. While, the limit equilibrium method proposed in this paper has fewer assumptions and clear physical meaning.
Integral Anti-Slide Stability Analysis of RCC Gravity Dam
Authors: Zhang Li , Pang Dan , Liu Jian
Published: March 2013

The main purpose of the gravity dam stability analysis is to examine the stability safety in all possible load combination cases. Combined with the engineering example, the method of modeling , loading and analysis for the gravity dam by ansys is introduced in this paper, then the limit equilibrium method and the strength reserve method are adopt to calculate the safety factor under two conditions. The results indicate that the two safety factors which are calculated under two conditions can all satisfy the standard requirement; it is reasonable to analyze the gravity dam stability through two methods.
Stability Analysis of High-Filling Embankment Based on Nonlinear Finite Element Method
Authors: Yang Li Na , Yao Kang , Xu Pei Hua , Zhang Guang Yi
Published: March 2013

To construct high grade road in the mountain area will meet the high rock filled embankment inevitably, the high rock filled embankment has become one important temp of the roadbed structure. This paper based on nonlinear elastic-plastic finite element method, by means of numerical simulation, under the stress of weight, external load, strain and displacement variation analysis, which can provide more reliable parameters for the design of High-filling embankment.
Analysis and Research of Cement Mixing Pile in Soft Ground
Authors: Wu Ji Yuan , Ju Yu Wen , Zhang Yu Cong
Published: March 2013

In this paper, through the design of the technical parameters, construction quality control points, the matters needs to be pay attention of cement mixing pile in soft ground treatment to analye the working properties in a flexible foundation of cement mixing pile and discuss the design methods of flexible foundation of cement mixing pile.
Taiyuan Underground Pipeline Testing and Analysis of Deformation and Failure
Authors: Chen Zhi Lei , He Wu Bin , Bai Xiao Hong
Published: March 2013

GEO-groove simulation experiment is applied to imitate the Taiyuan soil subsidence in pipeline base and side by soil loss, which eventually leads the pipeline to be deformed and destroyed. The pre-damage standard is set up though analyzing test statistics and drawing it’s sedimentation and damage curve. The damage standard of sewage line is achieved through setting up a very pilot model to the test and analyzing it’s bearing force characteristics, and according to the gotten sedimentation curve of the test, damage characteristics and mechanism of sewage line is analyzed , thus will give the designing and application of pipeline of testing and theory basement, so as to take measures to protect pipeline in practical situations, establish early warning system to pipeline, and guarantee it’s regular service.
Thermal Shock Behavior of a Functionally Graded Material Plate with a Crack
Authors: Zhang Yan Yan , Guo Li Cheng , Guo Feng Nan , Yu Hong Jun , Huang Kai , Feng Yu Bo
Published: March 2013

A thermal shock problem of a functionally graded material plane (FGMP) containing a crack is considered. All the material properties of the FGMP are assumed to be dependent on the coordinates.The transient temperature fields are solved by combining the finite difference method (FDM) and the finite element method (FEM). Then the transient thermal stress intensity factors (TSIFs) are obtained using the interaction energy integral method. The transient characteristics of the TSIFs are investigated.