bluuebunny/crossref_metadata_2025 huggingface dataset:
CAD/CAE on the Mould Plates of Horizontal Type High-Pressure Grouting Machine
Authors: Huang Zhi Cheng
Published: June 2012

In order to study the stress and strain of front and back mould plates of high pressure grouting machine, this paper took a type of ceramics for daily use horizontal type high pressure grouting machine as the object of study. Established its CAD model and analysed it with finite element analysis software. The analysis results can provide a reference for design, and have some engineering and practical value.
Analysis of Jib Strength and Broken Jib Accident of High Pedestal Jib Crane from the Perspective of Mechanics
Authors: Zeng Qing Dun , Liu Fang
Published: June 2012

According to an example of the broken jib accident of a high pedestal jib crane (HM2564) in a Shipyard Co., Ltd. in Guangdong province, this paper used a finite element software ANSYS to establish a solid model for the jib frame of the crane, calculated the stresses of jib system under various actual working conditions and checked the strengths. Simultaneously, the reasons of broken jib were quantitatively analyzed from the perspective of mechanics. The results show that the strengths of the jib system meet the requirements of safe use under all kinds of working conditions, but the related hoistman incorrectly operated the facility, cables can’t be winded normally in pulleys, thus resulting in that the tensile force of a cable was directly applied on the main jib by pulley spindle and the failure of the jib frame occurred under heavy compressive force of lifting cables.
Research on Energy Saving Mechanism of Optimal Regulation Voltage for Overhead or Gantry Crane Based on Mechanics Analysis
Authors: Zhong Bin , Cheng Wen Ming
Published: June 2012

For overhead or gantry crane direct relationship between electric total loss and stator voltage or load torque is obtained based on the asynchronous motor’s Γ-shape equivalent circuit because the stator’s copper loss and iron loss are regarded as invariable loss that only relates to stator voltage and the rotor’s copper loss is regarded as variable loss that is changed following load torque’s changing. The optimal regulation voltage is obtained through mathematical calculation on the condition that make the asynchronous motor be stable running. The electric total loss will be minimum when the stator’s voltage is the optimal regulation voltage. The research results showed: the electric total loss’s error between the exact solution and the approximate solution obtained according to the approximate slip ratio while the asynchronous motor’s stable running was bigger when the stator voltage was less than 200V, and the error was nearly zero when the stator voltage was more than 200V, but the optimal voltage error would not be more than 7V; the crane’s effect of energy saving was prominent with optimal voltage regulation mode according to the load torque’s changing.
Oscillatory Behavior in a Nonlinear Gyroscopic System with Mechanics
Authors: Feng Chun Hua , Lin Yuan Hua
Published: June 2012

In this paper, a nonlinear gyroscopic system is investigated. Two sufficient conditions to ensure the existence of oscillations for the system are proposed. Simulations are demonstrated for the provided results. In the study, the authors has researched the nonlinear gyroscopic system from the mechanics perspective, which will be useful in dynamic mechanical system, especially for parametric vibration. In fact, the nonlinear gyroscopic system is closely connected with mechanics, and they also influences each other during study.
Hydraulic Cylinder Cold Pulling Processing and Mechanics Analysis
Authors: Zhang Xi Xi , Jia Yu Jing , Cheng Guang Zhen
Published: June 2012

This paper describes a method about hydraulic cylinder cold pulling processing. Take seamless steel tubes as raw materials, they are acidified and phosphates before the cold pulling to guarantee that mold and pipe have a good lubrication and have a high temperature stability during the cold pulling processing, thus the cold pulling process can be stable . When the seamless steel tubes are brought into the drawing processing, a process provides with a Hydraulic pulling machine, matches special cold pulling die, then they occur plastic deformation uniformly and satisfy the dimension requirements ,whose accuracy can reach IT7~IT8 and the surface roughness is Ra0.4 ~ 0.6. At the same time, it causes producing cold hardening, which makes the material strengthened. Compared with the traditional processing methods, drawing processing can remarkably improve the production efficiency, ensure product quality and improve the qualification rate of finished products.
Failure Analysis of Rolling Bearing Based on Oil Monitoring Techniques with Mechanics Basis
Authors: Jiang Xu Feng , Liu Fang , Zhao Peng Cheng
Published: June 2012

To determine the failure cause of rolling bearing of a factory heating device, oil samples extracted from the recovery of lubricant oil and were tested by comprehensive oil monitoring techniques (including physico-chemical properties analysis, pollution degree detection and ferrography wear particle analysis). The results show that root cause of failure is the operating temperature of the bearing is too high. Failure form is burning. Therefore, the application of oil monitoring techniques to analyze the mechanical failure mechanism, to prevent mechanical failure and extend machine life is very helpful.
Study of Thermodynamics of Alkali-Free Glass Reaction
Authors: Liu Shan , Yao Yao Chun , Liu Yan Li , Dai Yong Nian
Published: June 2012

Thermal learn calculation was used on the process of glass melting of alkali-free glass, the relationship type between free enthalpy and temperature was obtained. Results show that B2O3 begin to melt at T=700 K, this reaction contained more step reactions. Carbonate barium (BaCO3) decomposed to generated BaO and CO2 around 1300 K, BaO began reaction with small amounts SiO2 to generate silicate. BaO and SiO2 were easy to react in low temperature because of their high reactivity. Reaction between SiO2 and Al2O3 was a reversible reactions, the turning point was T=1700 K. Combined with the calculation results, each reaction in different temperature range was discussed. In addition, the mechanism of reaction in the glass melting process was studied and discussed by use of thermogravimetric-differential scanning calorimetry.
Structure and Motion Analysis of a Tire Building Drum Based on Parallel Mechanism
Authors: Pan Xue Hai
Published: June 2012

A new type of tire building drum based on parallel mechanism was presented and the analysis of the structure was carried out.The calculation of dof and the output motion type analysis and positive solution and inverse solution were included. Solid model of the mechanism was set up and the trajectory analysis was conducted using software of UG and MATLAB, which provided theoretical base for optimal design application of the mechanism.
Design and Analysis on the Dynamic System of an Oil-Well Pump Lifting Test System
Authors: Li Biao
Published: June 2012

In order to meet the demand of the oil-well pump lifting test, designed a set of dynamic system, which can do long stroke reciprocating motion rapidly. On the use of composite liquid cylinder can effectively solve the problem of the load force is not the average when the cylinder moves reciprocally. The maximum lifting force of dynamic system is 120kN; maximum speed is 0.8m/s, reached the design index. At the same time, this set of dynamic system combined electro-hydraulic proportional control method and the oil production, provides a new exploring space.
Analysis on the Characteristics of Scale Wave Energy Dynamic System during Extended Period of the Massive Drought in Southwestern Region
Authors: Xiao Tian Gui , Wu Yao , Jin Rong Hua
Published: June 2012

Through the wave-packet propagation diagnosis (WPD), the essay discusses and analyzes the characteristics of wave packet distribution and dynamic system of wave energy propagation during the extended period of the massive drought in southwestern region in the country by using the reanalysis grid data of the daily NCEP/NCAR geopotential height field and 10×10 horizontal resolution from September 2009 to April 2010. The results show that: the characteristics of dynamic system of wave energy propagation at the middle and high height fields can better reflect the stage features of this drought during the period. The wave energy time-variation chart shows that the wave disturbance during the drought is weak and the wave packet value is small. However, the wave packet value during the drought still has some changes, reflecting the characteristics of the drought change in weakness. At the maintenance period of the wave packet value, the drought is often severe, and when the wave packet value changes greatly, the magnitude of the drought will change. Seen from the characteristics of longitudinal and altitudinal propagation of the wave energy, when the wav packet strength increases, the energy will accumulate and the drought tends to be weakened; on the contrary, when the wave packet strength decreases, energy will discharge and the drought will become more severe—particularly when the wave packet weakens quickly, the drought will become more drastic. This study provides a meaningful idea for discussing the forecast of the scale weather process during the extended period.
Study on Optimal Circulation Dynamic System and Feasibility Analysis for a Solar Biogas Digester
Authors: Zhang You , Peng Chang Sheng , Li Feng Min
Published: June 2012

According to biogas digester heated by circulation of water heated by solar cell, three modes of hot water circulation dynamic system (one-stage cycle, multi-stage cycle, and continuous cycle) were proposed to reduce operating costs and optimize the operation. The results obtained showed that multi-stage cycle had a clear advantage in improving operating efficiency, the heat transfer of which was 41.57KJ, much higher than 7.21KJ of one-stage cycle and 2.20KJ of continuous cycle. A model was built to simulate the overall process of heat dissipation in comparison with what was obtained from the conventional experiments. Both the simulation and the experimental measurement data showed that multi-stage circulation dynamic system operated well.
Research on the Characteristics of Gas Geology in Yongshanqiao Mining Area, Jiangxi Province
Authors: Zhao Zhi Gen , Zhang Ming Ming , Yan Jia Ping
Published: June 2012

The coal and gas outburst is very serious in Yongshanqiao Mining Area of Jiangxi province, so it is of significance to research the characteristics of gas geology and their controlling factors. Based on the statistical analysis of gas data during coal exploration and coal mining, the regularity is revealed of the characteristics of gas geology in Yongshanqiao Mining Area. From east to west and from south to north, the relative gas emission rate and the absolute gas emission rate tend to increase, the frequency and intensity of coal and gas outbursts rise, the gas contents also tend to increase. The controlling factors of characteristics of gas geology in Yongshanqiao Mining Area are researched in this paper. The work reveals that: corresponding to characteristics of gas geology, the distribution characteristics of coal quality, the characteristics of geological structure and the lithology characteristics of the roof and the floor of the coal seams in Yongshanqiao Mining Area present regular changes, and are all favorable to gas generation and gas preservation. So, the characteristics of gas geology in Yongshanqiao Mining Area are the result of comprehensive effects by geological factors
Research on Material Selection Standard of Graded Crushed Stone Base Course for Municipal Road
Authors: Liu Kai , Wang Fang , Zhang Wei Hua , Wang Yuan Rong
Published: June 2012

For reasonably selecting graded crushed stone materials, material selection standard is proposed for each traffic level of municipal roads according to the local common material properties in Anhui province, and referring to technical index provision and research results about graded crushed stone material at home and abroad. The selection standard of coarse aggregate takes crushing value, abrasion value, needle and plate particle content and robustness as index. The selection standard of fine aggregate takes robustness, sand equivalent, liquid limit and plasticity index as index. The research results promote the popularization and application of graded crushed stone base course on municipal road engineering in Anhui province.
A Comparative Study on Building Energy Performance between Movable and Fixed Shading Materials
Authors: Yang Xiao Chang , Yao Jian
Published: June 2012

The purpose of this paper is to investigate the effect of movable shading on building energy demands. A public building and a residential building with movable shading and fixed shading were modeled by the building energy use simulation software DOE-2. Cooling and heating energy demands were calculated. The results showed that movable shading is better than fixed shading.
Application of Fluorescent Aerosols to Verifying the Leakage of Protective Clothing by Image Processing
Authors: Luo Chin Hsiang , Chen Hong Zhou , Huang Yi Chin , Yang Shin Hao , Wang Sz Han
Published: June 2012

This work aims to measure the leakage of the personal protective equipment by using the fluorescent aerosol tracer. The fluorescent aerosols were employed as airborne particulates in a controlled chamber with ultraviolet (UV) light-detectable stickers. After an exposure and leakage test, the protective equipment was removed and photographed with UV-scanning to evaluate areas and color depth ratio of the areas where fluorescent aerosols had adhered to the body through the protective equipment. An image processor installed with an entropy-based algorithm was developed to segment the fluorescent area and calculate its relative leakage ratio (Lr) in real time. This study shows that the total leakage rate of the K brand protective clothing is 2.04 × 10-4 in two repetitions, and its 10- repetition total leakage rate is about 3.15×10-3. The two-repetition total leakage rate of the P brand protective clothing is about 2.47×10-4, and its 10 repetition total leakage rate is about 4.79×10-3. The two-repetition total leakage rate of the W brand protective clothing is about 1.04×10-4, and its 10-repetition total leakage rate is about 4.68×10-3.
Characterisation of the Sound and Vibration Signal of Impact Testing on Automotive Component Materials
Authors: Bahari Abdul Rahim , Nuawi Mohd Zaki , Abdullah Shahrum , Ihsan Ahmad Kamal Ariffin Mohd , Ali Mohd Basri
Published: June 2012

Dynamic response of automotive component materials which are carbon steel S50C and cast ironon its sound and vibration characteristichas been studied. This paper shows that I-kaz analysis method can be applied to characterise this dynamic behavior problem. In the present work, an excitation has been performed by an impact hammer at the center of a rectangular bar specimen instrumented with accelerometer and microphone to obtain sound and vibration time-histories. From the experimental results, it was found that the recorded sound and vibration signal has a transient characteristic with high oscillation. Frequency spectrum analysis shows that impact testing on any material will generate its own characteristic of frequency peak and constantboth for sound and vibration signal. From I-kaz analysis method, it can be concluded that I-kaz coefficient, for sound signal is proportional to the modulus of elasticity, density and Poissons ratio. It is also shown that for vibration signal is inversely proportional to these mechanical properties.Data scattering representation supported this pattern of .
Nonlinear State Estimation of Tire-Road Contact Forces Using a 14 DoF Vehicle Model
Authors: Louis Lawrence , Schramm Dieter
Published: June 2012

The knowledge of the wheel forces is fundamental to the development of Advanced Driver Assistance Systems (ADAS) such as Electronic Stability Control (ESC) and Anti-Roll Control (ARC). However the direct measurement of the wheel forces has been very difficult. To overcome this drawback, it has been a common practice in the industry to estimate the forces at the tire-road contact using mathematical vehicle models and estimators, especially the Extended Kalman Filter (EKF). In this contribution, the performance of the EKF is evaluated using a complete spatial model with 14 degrees of freedom.
Prediction of Fatigue Crack Propagation of Rail Material Using 2D Finite Element Modeling
Authors: Akeel N.A. , Sajuri Z. , Ariffin Ahmad Kamal
Published: June 2012

Fatigue crack propagation in two-dimensional rail track model under constant amplitude loading was analyzed using finite element method. The stress intensity factor was predicted using the displacement correlation method that was written in FORTRAN code and exported to Post2D to run the program and utilizing the singular elements around the crack tip area with automatic remeshing model. The fatigue crack propagation is modeled through the successive linear extensions under the linear elastic assumption. To simulate the propagation a single edge angled-crack was introduced to calculate the accurate values of stress intensity factors. The fatigue crack propagation for rail track under four point bend loading model was successfully simulated. The crack was initially propagated in direction inclined to the rail head surface but changed its direction 90° to rail head surface after certain crack length. The mix mode stress intensity factors were also successfully determined through the proposed model.
Analysis on Impact Performance of Aluminum Automotive Side Member
Authors: Salwani M. Salleh , Ali Aidy , Barkawi Sahari B. , Nuraini A.A. , Faieza A.A. , Tuan Ismail Tuan Hafandi , Nursherida J. Mai , Azizi Azim , Safar Nabilah Mohd , Satuan Siti Aini , Mohamad Shahril , Muhamed Norhidayah
Published: June 2012

In this study an aluminium alloy is introduced as an alternative lightweight material in automotive industry. In order to achieve lightweight design, the study was undertaken on a side member of automotive parts. Crashworthiness performance of AA5182 side member is compared to the automotive steel side member. By designing 16 experiments based on full factorial design, the effect of thickness with four levels on the crash performance of the AA5182 side member was investigated for each loading conditions, axial and oblique loading. Mass, energy absorbed and maximum force is set as the evaluation criterion and the full factorial design has presented several designs to serve the evaluated criterion.
Car Body and Chassis Development of UKM CARevo for Perodua Eco-Challenge 2011
Authors: Faizal Wan Mohd Wan Mahmood , Mohd Sabri Mohd Anas , Tahir Mohd Faizal Bin Mat , Ariffin Azli , R. Zulkifli , Jamaludin Nordin , Sallehuddin Mohd Haris , Ramli Rizauddin , Abdullah S. , Abdullah Shahrir , Shamsudeen A.
Published: June 2012

This paper presents the development of the UKM Perodua Eco-Challenge vehicle, CARevo in terms of aesthetic design, novel fabrication of car body and superior chassis design. The objective of the competition was to develop a fuel efficient car which was competent to travel the longest distance using 0.5 liter of RON95 fuel with some rules and regulation verified by the Perodua to be followed. The UKM CARevo was powered by a 660cc fuel injection engine with manual 5-speed transmission with the total of 3450 mm, 1500 mm and 1106 mm for its length, wide and height. Several design such as space frame chassis design, composite bodywork result from fiberglass with resin, aerodynamic design of car body and are the key features that is discussed in this paper.
Introducing Fatigue Contour Plot in LS-Pre Post LSDYNA Finite Element Crash Simulation Software
Authors: Aini S.S. , Barkawi Sahari B. , Ali Aidy , Nuraini A.A. , Faieza A.A. , Tuan Ismail Tuan Hafandi , Shahril M. , Nabilah M.S. , Salwani M. Salleh , Nursherida J. Mai , Azim A. , Norhidayah M.H.
Published: June 2012

In this study, a computer program for calculating fatigue life of component is developed and introduced in LS-PrePost software. The program is written in Fortran programming language and the fatigue life equations used is taken from well-published literature. The materials covered are steel and aluminum. The developed program is able to read stress, strain and element values from d3plot and the keyword file. Having extracted the output from d3plot and keyword file, the fatigue life is then calculated and presented into a separate file called FATIGUE. The integration of output from FATIGUE will is displayed in LS-PrePost. Finally, the results of fatigue life contour are successfully displayed through LS-PrePost.
A Study on Alternative Fuel Blending for Homogeneous Charge Compression Ignition (HCCI) Engine Using Palm Oil Methyl Ester and RON 97
Authors: Awaludin Azali , Nuawi Mohd Zaki , Yusoff Ali , Wan Mohd Faizal W.M. , Mohamad Taib Iskandar
Published: June 2012

This paper presents work conducted at the Universiti Kebangsaan Malaysia to support the HCCI Engine Program. The objective of this paper is to develop an engine that employs Homogeneous Charge Compression Ignition (HCCI) combustion and features using Palm Oil Methyl ester as fuel. A Novel of palm oil product usage for HCCI engine fuel was investigated. Different percentage of blend of Palm Oil Methyl Ester and RON 97 was tested using Digital Boom Calorimeter. An experiment based on 0%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% percentage blending between Palm Oil Methyl Ester and RON 97 produced results with an average of 39 MJ/g. Result shows that a high percentage blending of methyl ester with Ron 97 will increase the calorific value of fuel and this result also shows that a low pressure needed to ignite combustion in combustion chamber because of the high calorific value.
Evaluation of Driver's Pre-Driving Skill on a Driving Simulator Using the Intelligent Dynamic Event Classifier (IDEA) Approach
Authors: Saad Mohamad Hanif Md , Hussain Aini , Shukri Muhammad Faiz Mohd , Nor Mohd Jailani Mohd , Rosli Mohd Rezdwan
Published: June 2012

This paper reports the early results of the evaluation of driver's pre-driving skill on a driving simulator using the Intelligent Dynamic Event Analyzer approach. The IDEA Evaluator module, developed as an out-of-process Component Object Model ActiveX-Exe, is integrated into the ASISTM driving simulator to monitor drivers action during pre-driving activities. Fundamental actions detected from ASISTM simulator are fed to the Intelligent Dynamic Event Analyzer evaluator module and the result (Correct / Incorrect) is returned back to ASISTM. The integrated system was observed to be able to successfully evaluate the driver activities. The whole process is executed online utilizing ASISTM driving simulator module.
Experimental and Analytical Durability Assessment of SAE 1045 Steel under Service Loadings
Authors: Kadhim Nawar A. , Abdullah Shahrum , Ariffin Ahmad Kamal , Nik Abdullah N.
Published: June 2012

Durability assessment of automotive lower suspension arm has been studied under service loadings. The fatigue tests were conducting for the SAE 1045 steel based strain-controlled. To specify the material mechanical properties of the used material, a fatigue test under constant amplitude loading has been carried out then the results were provided for the finite element code. The finite element fatigue life were evaluated and compared with the experimental results. The accuracy and efficiency of the numerical models are demonstrated. This tool cannot be considered as a powerful alternative prior to the further experimental process. Instead, suitable fatigue prediction models under service loadings need to be developed.
The Study on Reconstruction Patterns of Urban Village by Game Theory - With Hohhot as an Example
Authors: Zhao Xiu Qing , Bai Yong Ping , Meng Jing
Published: June 2012

The article analyses the game process of various benefit corpus in the reformation process of urban village by establishing the game models, getting the combination forms of corpus and its strategies. Combining the three kinds of reformation forms of urban village ,such as reconstruction , adjustment and control ,and the especially actual circumstance of Hohhot ,the article puts forward the different reformation models to different villages.
Elastic Local Buckling Strength of Tapered H-Shaped Cantilever Beams
Authors: Yoshizawa Katsuhito , Ikarashi Kikuo
Published: June 2012

The purpose of this paper is to investigate the elastic local buckling strength and the behavior of tapered H-shaped beams under stress condition of cantilever beam. The analyses were conducted by separating H-shaped beam into two plate elements (web and flanges). From the results of analyses, authors evaluate elastic local buckling strength of each plate element, and clarify the several effects of tapered shape by comparing buckling strength and the behavior of tapered H-shaped beam with uniform H-shaped beam. In addition, authors examine coupled buckling of the two plate elements and confirm that the evaluations can be appropriate in case of coupled buckling.
Dynamic Characteristic Analysis on Experiment of Suspended-Span Structures in Water
Authors: Zuo Sheng Rong , Yang Ji Xin
Published: June 2012

The safety of dynamic characteristics plays a very important role of underwater structures today. In this paper, in order to analyze the dynamic characteristics of structures we have done several groups of experiments and tested the dynamic characteristics of the models in air and water respectively，then we calculated the natural frequency of the suspended-span structures in water using Additive Mass Method and compared with the experimental data. The results showed that the comparison between the experimental and calculated data is accordant, contemporaneously we tested the natural frequency in water with in air to the same specimen , it shows that the frequency of structure in water is lower than in air, but only little difference.
Experimental Study on Flexural and Fatigue Property of Steel Fiber Reinforced Prestressed Concrete Slab
Authors: Wang Shi Yue , Hou Jie , Huang Bi
Published: June 2012

The flexural strength of steel fiber reinforced prestressed concrete slab (SFRPCS) with different steel fiber volume ratio (0%, 1%, 2%) is obtained according to four-point bend test, which reveals that the addition of steel fiber can retard the crack growth and enhance the flexural strength of SFRPCS. With the results of fatigue experiment, the damage forms of SFRPCS is analyzed, strain amplitude-cycle ratio curves are obtained and the plastic strain energy of SFRPCS with different steel fiber volume ratio during fatigue process is calculated. It is shown that after 80% fatigue life, the more of the steel fiber volume ratio, the less of the strain amplitude increment, which proves the addition of steel fiber can prevent the concrete matrix from cracking and improve the fatigue performance of SFRPCS, and the plastic strain energy curve of SFRPCS shows obviously three- stage development.
Study on Explosion Resistance Performance of Injected Fluid Structure
Authors: Zhang Chao , Wu Wei , Li Yong
Published: June 2012

Based on simplified theory model of injected fluid structure, select steel plate as maintenance structure and water as test equipment of liquid production, do field tests of explosion and analyze explosion resistance performance of structure. The results show that the injected fluid structure has good explosion resistance performance and that its cutting-wave ratio reaches to about 85%. It provides experimental basis for explosion resistance performance of injected fluid structure in the explosion load.
Performance Degradation Assessment of a Beam Structure by Using Wavelet Packet Energy
Authors: Jiang Zeng Guo , Chen Bo
Published: June 2012

The evaluation on damage event of a beam structure is carried out in this study through an integration of knowledge in damage detection and signal process. A damage detection approach based on wavelet packet transform (WPT) is developed by decomposing and reconstructing the structural dynamic responses to obtain the signal energy distribution at different levels. The WPT coefficients are reconstructed to extract the signals in various frequency ranges and determine the signal energy in different frequency bands. A WPT component energy index is proposed to establish the slope vector as well as curvature vector and then the judge on the slope vector and curvature vector can indicate the damage event. Parametric study is carried out to investigate the relationship between the index amplitude and the damage extent. The results from this study demonstrate that the detection approach proposed can accurately identify the damage event in the structure.
Study of Hybrid Method on Beam Crack Evaluation
Authors: Du Chuang , Li Sen , Li Yan Yan , Du Zi Tao
Published: June 2012

Based on the numerical calculation and the theoretical formula for crack width,a new semi-numerical and semi-theoretical calculation formula for crack width of beam was given. By using this new formula,finite element method and theoretical method is combined. The method has been validated with the beam, it is indicated that the proposed method can be used to calculate the crack width of beam accurately and efficiently.
Crack Formation and Strength of Fire Damaged Concrete Beam
Authors: Srisoros Worapong , Kaewpetch K , Ariyasuk P , Chokcharoenmahasarn A
Published: June 2012

The Rigid-Body-Spring-Model was applied for analyzing fire-damaged concrete beam with voronoi random mesh. Material models of fire-damaged concrete was defined by the experiment. To evaluate the performance and effectiveness of the RBSM with voronoi random mesh, four models of fire damaged concrete beam at various temperatures covered 20°C and 100 to 800°C were analyzed. According to the results, heated specimen 800°C has the lowest strength capacity and internal stress comparing to the other specimens. Main crack of 800°C specimen appears earlier than other specimens. Strength capacity of heated specimen 400°C was higher than the results of unheated specimen because of hydration reaction of large cement clinker was accelerate during heating.
Numerical Analysis of Top Ring Beam for Foundation Pit
Authors: Xu Hai Yong
Published: June 2012

The research and application condition of top ring beam for the foundation pit engineering is introduced. A 3D finite element model of row piles and top ring beam is calculated and several major parameters of the beams are discussed. On the basic of the FEM results, a simplified method is proposed to calculate the equivalent stiffness of the beam in a typical design profile for practical engineering.
Experimental Research on Damage Detection of Concrete Structures Based on Piezoelectric Smart Aggregates
Authors: Meng Yan Yu , Yan Shi , Sun Wei
Published: June 2012

The piezoelectric ceramic (PZT) smart aggregates as sensor and actuator were embedded into large eccentric compression column to generate sin-sweep signals on-line and detect real-time signals before and after damage. The PZT active health monitoring and wavelet packets energy method were focused experimentally on the effectiveness validation of damage detection. The index of root mean square deviation is used to evaluate the damage information by compare of the energy change of damage signals. A statistical pattern identification algorithm is proposed by wavelet packets decomposition and statistical characteristics analysis of damage signal amplitude. The results show that the amplitude of active monitoring signals produces a larger attenuation. The sweep wave signal as active health monitoring is an effective method to identify damage degree and general location of concrete structure. The developed method can primarily be used in the damage evaluation.
Optimal Sensors Placement Based on Modal Strain Energy
Authors: Zheng Heng Bin , Yan Quan Sheng , Hu Jun Liang , Chen Zhou
Published: June 2012

For a space simply supported truss bridge model, a method named element modal strain energy (MSE) was firstly adopted in the field of the optimal sensors placement. By taking nodes MSE, nodes distance matrix reciprocal as weights, and combining with optimal matching in graph theory, how to apply the method for optimal sensors placement was stated. Through analyzing on the random vibration property of the bridge finite element model, the nodes position of larger acceleration response was compared with the optimal placement got from the above method, which could verified the effectiveness of optimal sensors placement.
A Multi-Hierarchical Damage Identification Method for Jacket Platform Using BP Neural Network
Authors: Chen Xiang Yu , Dong Sha Sha , Liu Fu Shun
Published: June 2012

Jacket-type platforms may be the most common type of offshore structures, and damage localization and severity estimation is important for these structures. This paper employs a multi-hierarchical damage identification method based on BP neural network to detect damages in jacket platforms. Firstly, the damaged storey of the jacket is detected, and the numbers of the elements among the detected storey are then detected. According to this method, the learning samples can be more targeted and the number can be reduced largely. In the end, a jacket model is used to investigate the performance of this method, and the results indicate that this approach is more effective and has higher accuracy than direct diagnosis method.
Complex Genetic Algorithm for Structure Shape Optimization Design of Mixed Discrete Variables
Authors: Zhu Chao Yan , Liu Jing Yu , Liu Hong Yan , Wang Xue Zhi
Published: June 2012

Discrete complex method is used in genetic algorithm(GA) and a mixed genetic algorithm called complex genetic algorithm(CGA) is formed. The complex method used here increases the quality of species groups, and improves the searching efficiency. The mixed genetic algorithm method is used in the shape optimization for mixed discrete variables. The integration and coding of the shape variables and the cross-section variables in genetic algorithm can not only solve the coupling problem of two kinds of variables, but also avoid the partial optimum solution resulting from the separation of the two kinds of variables. The result of the exemplification indicates that the complex genetic algorithm for structure shape optimization design of mixed discrete variables is effective.
Research on Plate Damage Detection by Two-Dimensional Wavelet Analysis
Authors: Guan De Qing , Xiao Xiao Quan , Zhong Xiao Lin
Published: June 2012

Wavelet analysis has the characteristics of timing and frequency adapting to each other. Two-dimensional wavelet analysis can rotate and amplify the signal in frequency domain. So, in this paper, two-dimensional wavelet analysis is used to detect the position of the injury of simply supported plate. This article simulates an injury and two injuries in a simply supported plate and the detection of the location of the injury. This article verifies that the feasibility of this method.
Hybrid Control for Seismological Nonlinear Structures on Liapunov’s Theory
Authors: Pan Ying , Zhao Tong
Published: June 2012

In this paper, the hybrid control method of earthquake excited high-raised buildings is put forword. The building is modeled as a shear-wall type structure with non-linear hysteretic restoring forces after the structure enters the period of nonlinear and plasticity. A passive base-isolation is combined with actuators applied at the basement of the structure. A candidate for Liapunov function is found out based on the theory of energy. A non-linear control law is designed following the theory of Liapunov, since small residual deformations have to be tolerated due to inelastic energy dissipation, asymptotic stability will not be required, but only stability in the sense of Liapunov has to be guaranteed. Computer simulations demonstrate the efficiency of the proposed control algorithm.
Experimental Study about Testing Masonry Shear Strength with Drilled Core Method
Authors: Cui Shi Qi , Kong Xu Wen , Wang Xin , Yang Ming Liang
Published: June 2012

Key technology of testing masonry shear strength with core drilling method is that standard shear strength of masonry is determined from the shear strength of masonry core sample, while current code or specification has not provided the corresponding calculating formula. To investigate their relationship, a series of tests have been carried out. Existing test result analysis shows that standard shear strength of masonry and shear strength of masonry core sample are closely related. By means of testing data regression analysis, this work can establish the relationship formula between shear strength of single core sample and standard shear strength of masonry. This Technology can be suitable both to traditional masonry structure and to new wall materials masonry structure, especially to seismic appraiser and reinforcement calculation of masonry structure. This technology can support scientific basis to quality examination and assessment of new wall materials and analysis of engineering quality accident.
A New Abnormal Index Based on Frequency Change for Structural Health Monitoring
Authors: Song Yan Sheng , Sun Zong Guang , Zhao Nai Zhi
Published: June 2012

This paper demonstrates a new abnormal index based on frequency change for structural health monitoring (SHM) which utilizes probability and statistics method. And it was introduced to analyze a steel frame. The results show it could indicate the abnormity of corresponding test cases clearly.
Experimental Investigation on Wide-Span Cold-Formed Steel Roof Truss System
Authors: Mohammad Shahrin , Tahir M.Md. , Tan Cher Siang , Shek Poi Ngian
Published: June 2012

The needs of environmental conservation and speed development in construction industry today have forced the search for better technologies in structural roof truss construction. Cold-formed section is a better choice for roof truss system in sustainable design with several advantages e.g. reduce cutting down of trees, speedy in construction, stronger, lighter and flexible in erection. However the stability issues occurred when wide-span roof truss is implemented with thin-walled cold-formed steel member. A full scale testing for a 25 meter wide-span roof truss system was carried out at Universiti Teknologi Malaysia to study the structural performance. The overall span of the truss is 25m in length with the height of 4.7m and the width of 1.2 m, built up by cold-formed steel channel sections of 150 mm and 74 mm in depth. Uniform loads were placed on the top and bottom chords of the truss using cement bags. The roof truss deformed at a total load of 63.77 kN or 52.7% of the designed load. Failure modes of the truss system were being observed and discussed for further improvement of the truss design.
Monitoring Strain Study of Cylinder Caisson Based on Fiber Grating Sensing Technology
Authors: Chen Yao Hui , Zhou Jing
Published: June 2012

A structural health monitoring system by fiber Bragg grating (FBG) sensing technology was installed on 8 # berthing pier of cylinder caisson in a new 300,000 DWT crude oil berth pier of Dalian Port. The system can realize the timely strain monitoring and timely cumulative damage identification of the structure. By analyzing the monitoring data of 8# cylinder caisson under wave load, this paper gives the strain rules and provides the reference for the safety assessment. The study results also have pratical significance on similar structures’ further research.
Experimental Research on the Ductility of High Performance Concrete Beams
Authors: Yun Ying Wei , Luo Qin , Jang Il Young , Sun Shan Shan , Zhang Jia Wei
Published: June 2012

Ductility is important in the design of reinforced concrete structures. In seismic design of reinforced concrete members, it is necessary to allow for relatively large ductility so that the seismic energy is absorbed to avoid shear failure or significant degradation of strength even after yielding of reinforcing steels in the concrete member occurs. This paper aims to present the basic data for the ductility evaluation of reinforced HPC (high performance concrete) beams. Accordingly, 10 flexural tests were conducted on full-scale structural concrete beam specimens having concrete compressive strength of 40, 60, and 70 MPa. The test results were then reviewed in terms of flexural capacity and ductility. The effect of concrete compressive strength, tension steel ratio, and shear span to beam depth ratio on ductility were investigated experimentally.
Field Experiment Study on the Bearing Characteristics of Squeezed Branch Pile in Loess Area
Authors: Cui Wen , Wang Zi Jing
Published: June 2012

The load-transferring mechanism under the action of vertical load and the role of bearing load by bearing disks in loess area were analyzed based on results of field static loading test of the squeezed branch piles. The results indicate that load transfer law of squeezed branch pile is transferred from top to bottom, and load of bearing disks is about 60 percent of the top load of the pile, stress superposition efficiency existed between bearing disks, and the minimum critical spacing of disks is 2D (D is the diameter of the bearing disk), the estimated bearing capacity of the squeezed branch pile is higher than the measured value.
Impact Evaluation of Mud Cake Thickness on Shearing Strength at Cement-Formation Interface
Authors: Gu Jun , Yang Bao Lin , Yang Yi Jun , Ma Chao , He Ji Biao , Li Ke
Published: June 2012

In order to evaluate the impact of mud cake thickness on shearing strength at cement-formation interface accurately, a feasible simulation experiment system and evaluation method was established, which includes preparation of artificial core, formation of mud cake, maintenance of the samples and testing of the Shear bond strength of cement-formation interface. Based on this, by taking commonly used drilling fluid from Shuangjiang oilfield, Jinglou oilfield and Zhongyuan oilfield in China as examples, the laboratory impact evaluation results show that: (1) As for different drilling fluid system, the shearing strength at cement-formation interface of the cement-formation interface keeps a general tendency to an obvious decline as the growing of the mud cake thickness. (2) In the same drilling fluid system, though different in the time of maintenance, the variation trends that the shearing strength at cement-formation interface declines as the growing thickness of the mud cake are similar. (3) The declining rate of shearing strength at the cement-formation interface will reach 83.4 %-99.9 % when the mud cake thickness is 5mm. These developments of this paper can be used to optimize the design of drilling fluid and cementing technology, and consequently improve the cementation quality of cement-formation interface to meet the demands of highly-efficient petroleum production.
Analysis of Kinematic Behavior on Landslide Groundwater at K144 Section along Da-Yu Highway
Authors: Wang Hao , Wang Quan Cai , Xu Xiao Ling , Wu Qing
Published: June 2012

Most of landslides occurred because of the action of water. Dynamics of groundwater is directly related to the stability of landslide. Change of groundwater level is one of the most important factors of landslide prediction. In this paper, We used waterclocks to monitor groundwater level of K144 landslide for two years and found that different slope regions of the groundwater level showed different variation. Groundwater level of unstable region changes between 4m ~ 6m in the sandy mudstone area where average precipitations is about 1000 mm, which were the same trend with the monthly total rainfall changing; groundwater level of stable area changes around 1.5m, which was unobvious in response to the monthly accumulative rainfall; the rise of groundwater level is the important reasons for the K144 landslide sliding.
Dynamic Stability Analysis of Big Span Steel Tubular Truss
Authors: Pan Dong Yi
Published: June 2012

An arch-truss roof structure with circular steel tube is applied to a gymnasium. Natural frequency and modes of this overall roof structure are analyzed, and time-procedure analysis is acted by applying ANSYS software. The analysis results demonstrate that this roof structure has larger stiffness, and its maximum node displacement under earthquake（7 degrees）can meet the requirements.
Bond Behaviour between Recycled Aggregate Concrete and Corroded Steel Rebars
Authors: Lei Bin
Published: June 2012

In this paper, corrosion percentages ranged from 0 to 7.62% of steel rebar for pulling out specimens was controlled by the accelerated method of electrochemistry. According to the RILEM standard, pulling out test with dimensions of 200×200×200mm3 and recycled aggregate concrete (RAC) of C30 was carried out, and the load versus slip curves between RAC and corroded steel rebars with different corrosion percentages were recorded. Based on the experimental results, the effect of RAC and reinforcement corrosion on the bond behaviour between steel rebars was investigated. The results show that the bond strength between RAC and deformed bars increases with corrosion up to a certain amount, and then the bond strength decreases as the corrosion rate further increases, which is similar to that of normal concrete. However, the decreasing rate of the bond strength between RAC and corroded steel rebars is much faster than that between normal concrete and corroded steel bars. According to the testing results, the relationship of bond stress-slip between corroded bars and RAC was given in the end.
Structure Observation & Identification Considering Soil-Structure Interaction of Story Stiffness and Damping Ratio of 8-Story Steel Encased Reinforce Concrete Structure by Microtremor
Authors: Ren Jun , Morita Koichi , Pan Ji Shun
Published: June 2012

In this article, the authors identify the one built in 1998, eight-story structure of steel reinforced concrete body dynamic parameters, and discussed the soil - structure interaction on the identification results.In this study, an 8 degrees of freedom analytical model and the impact analysis model of soil-structure interaction to be established; through the analysis of microseismic observations, using non-parametric (transfer function and Random Decrement method) and parameter techniques (off-line system identification method, ARX :Auto-Regression with eXtra input) to identify the structure of the natural frequency, damping ratio and the story stiffness. Finally, in considering the soil-structure interaction cases, structural parameters were identification and compared the results to confirm the impact of soil-structure interaction.
Optimization Design of Core Thickness of Exterior Frame and Core Hybrid Structures in High-Rise Buildings
Authors: Zhang Shu Yun , Zhao Wen Wei , Wang Hai Hua
Published: June 2012

Considering core thickness is important issue to performance of exterior frame and core hybrid structure in high-rise buildings, seismic response analysis is conducted by response spectrum method for finite element models with different core thickness. The optimization design of core thickness of hybrid Structures on the basis of the seismic response is studied, the core thicknesses are chosen as design variables, the objective function about core volume is adopted, some specification requirements such as deformation, the ratio of lateral stiffness to gravity, storey shear to gravity, storey shear of exterior frame, axial compression ratio of column and wall limb, bearing capacity of structural member and core construction are regarded as restricting conditions, the optimal mathematical model is established for reflecting integrity dynamic properties of hybrid structure. The ANSYS software is used for optimizing tool, the hybrid structures optimization design are made through different initial values for verifying convergence of optimization method, the optimal result show that the performances of hybrid structure are improved, the internal forces are reduced and the ratios of inner force born by exterior frames are increased in the optimal scheme.