bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics of Sulfuric Acid Leaching of Boron Slurry
Authors: Gao Feng , Xu Xiang Guang , Li Lei , Sun Huai Yu , Wang Hong Xin
Published: October 2011

The results of a leaching kinetics study of boron slurry with sulfuric acid were presented. Effect of ore particle size, reaction temperature, and acid concentration on magnesium dissolution rate were determined. The results shown that leaching of about 64.61% of magnesium was achieved using (-200+ 250) mesh ore particle size at a reaction temperature of 60°C for reaction time 100 min with 25% sulfuric acid concentration. Leaching kinetics indicated that diffusion through the product layer was the rate controlling process during the reaction. The reaction activation energy was determined to be about 3.35 kcal/mol, which was characteristic for a diffusion– controlled process.
A New Outlier Detection Algorithms Based on Markov Chain
Authors: Yang Jun , Wang Ying Long
Published: October 2011

Detecting outliers in a large set of data objects is a major data mining task aiming at finding different mechanisms responsible for different groups of objects in a data set. In high-dimensional data, these approaches are bound to deteriorate due to the notorious “curse of dimensionality”. In this paper, we propose a novel approach named ODMC (Outlier Detection Based On Markov Chain)，the effects of the “curse of dimensionality” are alleviated compared to purely distance-based approaches. A main advantage of our new approach is that our method is to use a major feature of an undirected weighted graph to calculate the outlier degree of each node, In a thorough experimental evaluation, we compare ODMC to the ABOD and FindFPOF for various artificial and real data set and show ODMC to perform especially well on high-dimensional data.
Research of 3D Woven C/C Composites Bending Properties
Authors: Yang Cai Yun , Zan Xiu Ping , Hu Zhen Ying , Li Jing
Published: October 2011

Two different kinds of structural preforms were designed and manufactured, which were 3D layer-to-layer angle-interlock structure and 3D solid orthogonal panel structure. C/C composites were made first by chemical vapor infiltration (CVI) and then liquid resin impregnation for complementation. The bending properties of the two 3D woven reinforced C/C composites were tested and analyzed. The inner microstructures were investigated by SEM. The results show that the bending property of 3D solid orthogonal panel preform reinforced C/C composites is higher than that of 3D layer-to-layer angle-interlock preform reinforced C/C composites, and the bending rupture of the former is brittle, the latter is tough.
Challenges Faced by SMEs in Developing Countries in Implementing Cleaner Production (CP)
Authors: Agwa-Ejon J. , Fore S.
Published: October 2011

Cleaner production (CP) has been widely recognized as a useful approach to mitigate pollutions during industrial production. Small-to Medium-Scale Enterprises (SMEs) contribute immensely to most developing economies and provide a vital source of employment and incomes for many millions of people in developing countries, but there is often disregard for the negative implications on the environment. The aim of the study was to assess barriers to cleaner production implementation in the small scale industries and recommend ways of addressing these. The research focuses upon some of the key environmental issues in the Zimbabwean small-to medium scale industry. An application of CP to two industries, namely the foundry and cement manufacturing industry is highlighted and the challenges faced during the implementation are discussed. A review of literature is also carried out to relate the challenges to other countries in order to have a global view and ascertain common inter-phases and the possibility of common solutions in the developing world. It was discovered that in the absence of external motivators, such as government regulation and community pressure, SMEs are less likely to adopt rapid advances in environmental performance. Lack of information also impacts negatively on efforts to inculcate a culture of environmental conscious manufacturing. There is a great need to actively inform the SMEs enterprises on the merits and demerits of not employing environmentally friendly methods of production. The other big barrier is the lack of expertise to champion the implementation of a companywide CP programme. Changes in systems and technology may also make certain employees obsolete, and therefore induce organisational structural protection of the existing system.
Modeling Flank Wear Hardness of Selected HSS and HCS Single Point Cutting Tools with or without Cutting Fluid
Authors: Kareem B. , Idris M.O.
Published: October 2011

Conventional tool monitoring instruments are usually costly to acquire. The instruments are inadequate for real time wear measurement in the uncertain environmental conditions of developing countries. A modeling approach relating relevant parameters causing wear on cutting tools’ flank will be useful in predicting wear in machining operations. Mild steel turning experiment was carried out on the lathe using selected High Speed Steel (HSS) and High Carbon Steel (HCS) single point cutting tools. Speed, feed, and time of machining were varied accordingly, while running with, and without coolant. Hardness of the cutting tips of the tools was measured using Rockwell, R hardness tester. The corresponding speed, feed and time of machining were also noted. Turning operation was continued until the tool was totally blunt. At this stage recorded values of hardness, time of machining, feed and speed were modeled using multiple regression technique, with and without cutting fluid. The resulting models were strongly in agreement with the measured values. Therefore, the model is a good predictor of flank wear for the selected tools commonly used in developing countries. The findings showed that wear of the cutting tools can be predicted during machining at predetermined cutting conditions.
Computer Aided Costing (CAC) for Sand Casting Products
Authors: Mogaji P.B. , Adejuyigbe Samuel B.
Published: October 2011

A suitable Computer-Aided Costing (CAC) software program using Matrix Laboratory Language (MATLAB) for costing of sand casting products was developed. It makes use of product mix model that was also developed which was used as input for both the computer and manual calculations. The model and program were applied to the costing of products made from aluminum, cast iron and brass. The Computer Aided Costing (CAC) results were compared, analyzed and correlated with the hand calculated costing results giving a correlation of 99.9%.
Thermal Management Materials for Electronic Control Unit: Trends, Processing Technology and R and D Challenges
Authors: Otiaba K.C. , Ekere N.N. , Amalu E.H. , Bhatti R.S. , Mallik S.
Published: October 2011

The development of advanced thermal management materials for Electronic Control Unit (ECU) is the key to achieving high reliability and thus safety critical operations in areas of ECU applications such as automotives and power systems. Thermal management issues associated with the operation of ECU at elevated temperature have accounted for some of the recent reliability concerns which have culminated in current systems failures in some automobiles. As the functions of ECU in systems have increased in recent times, the number of components per unit area on its board has also risen. High board density boosts internal heat generated per unit time in ECU ambient. The generated heat induces stress and strain at the chip interconnects due to variation in the Coefficient of Thermal Expansion (CTE) and thermal conductivity of different bonded materials in the assembly. Thermal degradation could become critical and impacts device’s efficiency. The life expectancy of electronic components reduces exponentially as the operating temperature rises thus making thermal management pivotal in electronic system reliability. Since materials’ properties vary with operating condition, material performance has become a major consideration in the design of heat dissipation mechanism in ECU. The development of advanced thermal management materials and hence improving the performance of ECU requires an in-depth understanding of the complex relationship between materials’ properties and their behaviours at elevated temperatures. The paper presents an overview of thermal management materials, review trends in material and processing technology. In addition, the paper outlines the crucial challenges in materials, cost and composite formulations and the outstanding R & D issues.
SEM Studies of Adhesion Property of Red Oxide Primer on Selected Metal Substrates
Authors: Bolarinwa M.A. , Adetunji A.R. , Adewoye O.O.
Published: October 2011

The Scanning Electron Microscope (SEM) has been used to study the adhesion of red oxide primer on selected substrates. The substrates are stainless steel, mild steel, galvanized steel and aluminium. Twenty (20 No) specimens were prepared from the four different substrate metals and examined metallographically, after coating them with red oxide primer using different methods of application. Results showed varying degrees of adherence. The red oxide primer was able to form bonds with the different substrate metals, especially with the well cleaned, primed and subsequently painted stainless steel specimen.
Cost Effectiveness of Scheffe’s Optimized Five-Component-Concrete with Mound Soil as a Mix Component
Authors: Orie O.U. , Osadebe N.N.
Published: October 2011

The paper examined the cost benefit of optimized five-component-concrete mix. Mound Soil randomly selected from Iyeke-Ogba in Benin City was used as a case study of a fifth component in the concrete mix. The work applied Scheffe’s optimization technique to obtain concrete mix proportions. A mathematical model for the optimizing concrete of five components namely; cement, fine aggregate, mound soil, coarse aggregates and water/cement (w/c) ratio, was developed. Cube samples measuring 150mm x 150mm x 150mm were made with the developed mixes and compared with the results of a standard 1:2:4 mix. The samples were tested at 7, 14 and 28 days for compressive strength. The costs of producing a unit volume of the concretes were determined and compared. The results showed that the standard mix gave a 28th day maximum strength of at a w/c of 0.5 and the theoretically optimized design mix gave a mix proportion of 1.00:1.59:0.46:3.34:0.53 and a compressive strength of. This mix was tested experimentally and it gave, representing an increase of 15.33%. The cost benefit analysis showed that Scheffe’s optimized mound soil concrete, MSC was 15% more economical than the standard mix plain concrete.
A Computer-Aided System for Job-Shop Flow Time and Due–Date Prediction
Authors: Akinnuli B.O. , Oluwadare S.A. , Aderoba Adeyemi A.
Published: October 2011

: One of the key challenges confronting a production system is the accurate prediction of flow time (completion time) and due date of jobs coming into the job-shop. The inaccuracy in the determination of flow time and due date could lead to problems of dead line misses, high holding cost for waiting jobs and/or completed jobs, technical and cost inefficiency; and customer dissatisfaction, among others. In this paper, a Computer-Aided System which is based on an empirical model for predicting job-shop flow time and due-date was developed. The Computer-Aided System makes use of historical production data and other peculiar in-house factors of an organization. The Computer-Aided System was tested with real life job-shop data in order to test its efficiency and it was found to be efficient in predicting flow time and due date of jobs.
Development of a Heuristics Model for Simplifying a Multi-Channel Queuing System
Authors: Kareem B. , Aderoba A. A.
Published: October 2011

Queuing model has been discussed widely in literature. The structures of queuing systems are broadly divided into three namely; single, multi-channel, and mixed. Equations for solving these queuing problems vary in complexity. The most complex of them is the multi-channel queuing problem. A heuristically simplified equation based on relative comparison, using proportionality principle, of the measured effectiveness from the single and multi-channel models seems promising in solving this complex problem. In this study, six different queuing models were used from which five of them are single-channel systems while the balance is multi-channel. Equations for solving these models were identified based on their properties. Queuing models’ performance parameters were measured using relative proportionality principle from which complexity of multi-channel system was transformed to a simple linear relation of the form = . This showed that the performance obtained from single channel model has a linear relationship with corresponding to multi-channel, and is a factor which varies with the structure of queuing system. The model was tested with practical data collected on the arrival and departure of customers from a cocoa processing factory. The performances obtained based on average number of customers on line , average number of customers in the system , average waiting time in line and average waiting time in the system, under certain conditions showed no significant difference between using heuristics and analytical models.
Development of a Small Scale Sugarcane Juice Extractor Using a Screw Pressing System
Authors: Olaniyan A.M. , Babatunde O. O.
Published: October 2011

A small scale sugarcane juice extractor using a screw pressing system was designed, constructed and tested. Consideration was given to the techno-economic status of the micro and small scale sugarcane farmers and juice processors who are the intended users of the machine. The functional parts of the machine included grating unit, extraction unit, prime mover, pulley, transmission belts, bearings and frame. The machine was tested with two varieties of sugarcane each at three levels of moisture content and results showed that average grating efficiency and juice yield of 87.8 % and 2.5 % respectively were obtained. Powered by a 3 hp single-phase electric motor, the machine was constructed with materials being available locally at affordable costs. A cottage sugarcane juice extraction plant based on this technology could provide employment and at the same time produce sugarcane juice and bagasse at low costs for sugar and biofuel industries. An improvement in the design, analysis and optimization of the worm shaft and press cage is expected to improve the juice yield and extraction efficiency; hence, this is highly recommended.
Development and Performance Evaluation of a Cocoa Pod Breaking Machine
Authors: Aliu S.A. , Ebunilo Patrick
Published: October 2011

Breaking of cocoa pods in order to release the beans presently constitutes a difficult task for Nigerian cocoa farmers. The traditional method of using wood and machete to break the pods is not only laborious and time consuming but also uneconomical. An electrically operated cocoa pod breaking machine has been designed, fabricated and tested. The machine which utilizes roller mechanisms was fabricated using locally sourced materials. Cocoa pods were categorized as big, medium and small based on their mid diameter sizes. The mid diameter size of the small category was most useful in determining the size of the breaking chamber. Pod breaking efficiency of over 95% was achieved during testing. Bean damage, a common feature of traditional methods and existing hand operated cocoa pod breaking machines was reduced to negligible proportions.
Current Trends in Water Resources Research
Authors: Taigbenu Akpofure E.
Published: October 2011

Research has largely been driven by the quest for innovation, new knowledge and improving the general wellbeing of the human race. Monumental challenges that plague humanity tend to, from time to time, shape research and take it to new heights, and one of such is the global water crisis [1,2]. To restate the obvious that water is the basis of life and the engine for social and economic growth, water resource engineering research attempts to address challenges related to: (i) how water of sufficient quantity and quality can be made available to meet various competing sectoral demands; (ii) how development and exploitation of the resource can be carried out in a sustainable manner so that its benefits extend to future generations; (iii) what adaptation and mitigating measures can be put in place to minimize the impacts of global climate change. This paper, therefore, presents trends in four areas of research in water resources engineering that focus on the paradigm shifts in water supply and sanitation, integrated modeling in order to give quantitative expression to integrated water resources management (IWRM), thereby achieving a more defined space for decision making, new and emerging cost-effective water treatment technologies, and research developments in adaptation measures to climate change.
Application of Erosion 2D Model for Erosion Studies in Makurdi Metropolis of Benue State, Nigeria
Authors: Isikwue M.O. , Amile T.G.
Published: October 2011

The equations of Erosion 2D Model (a physically based model) were transformed into a computer programme called EROSOFT and used to predict the rate of soil loss in Makurdi metropolis. The model has detachment, transport and deposition components. Four sites were chosen within the metropolis for this study. Soil samples were collected from the sites for laboratory analysis. Rainfall and runoff fluids were collected from the sites to determine their densities. Levelling instrument was used to detremine the channels slopes. The model predicted an average annual soil loss rate of 310kg m-2s-1 for the metropolis. The sensitivity analysis of the model indicates that straight slopes are more prone to soil erosion. The result of the model deviates slightly from established facts that, sandy soils are more erodible and hence prone to be easily detached. Nevertheless, the model shows that soil erosion is influenced by slope geometry and rainfall intensity. The study attributes the major causes of soil erosion in the city to urban runoff concentration and removal of vegetation, and therefore suggests the use of land grading, land forming and cover cropping as well as conservation structures like road side drains for the control of erosion in the metropolis.
Simulink Implementation of Direct Torque Control Drive for Induction Machines
Authors: Zangina U. , Yahaya H.N. , Aminu M. , Niyi Z.O.
Published: October 2011

Direct Torque Control (DTC) has emerged over the last two decades as a suitable alternative to the well-known Field Oriented Control (FOC) or vector control technique for electric drives mainly due to its simple control scheme, low computational time and reduced parameter sensitivity. In this paper, speed control of an induction machine based on DTC strategy has been developed and a comprehensive study is presented. The performance of the control method has been demonstrated by simulations using the Matlab/Simulink software package. Several numerical simulations have been carried out in steady state and transient operations.
Power Distribution in Lagos Metropolis: Assessment of 132kv Network Capacity
Authors: Melodi Adegoke Oladipo , Olomo O.G.
Published: October 2011

In this study, Lagos power distribution network at sub-transmission voltage (132 kV) was modeled and assessed. This is very relevant for the planning of effective electricity supply to the economic capital. The expected power demand of the metropolis was determined and the normal mode parameters computed for numerical analysis. The study was done for two scenarios: unilateral and multilateral injection of power into the network, using matrix algebra of mode linear equations by current balance. Analyses of results show that the total capacity of existing 330 kV/132 kV injection sub-stations is 1.71 GVA. The apparent power required to feed Lagos metropolitan 132 kV network is about 2.5 GVA (at 0.89 power factor), when power is injected through all the 330kV/132 kV injection substations. However, power transferred in the network lines is only 0.93 GVA at 0.9 power factor and at 97.4% efficiency. The power transfer capacity of the132 kV network lines alone is adequate when all injection stations simultaneously supply electricity. Any condition (emergency or otherwise) allowing only unilateral in-feed option at 132 kV, will lead to inadmissible voltage drops and overload conditions of lines unless drastic load shedding measure is applied. The total capacity of 330 kV/132 kV injection substations is inadequate by about 0.74 GVA (29 %). The total power required cannot be met by existing local thermal station of about 1.32 GVA maximum; the generating capacity development of Lagos should be looked into critically.
Numerical Study on Concrete Filled GFRP-Steel Tube under Cyclic Loading
Authors: Zhu Chun Yang , Zhao Ying Hua , Wang Dong Sheng
Published: October 2011

For the purpose of investigating the strengthening effectiveness of GFRP on concrete filled steel tube structure under combined seismic loading and comparing with CFRP ones, numerical simulations of quasi-static test are developed by using ABAQUS. The establishment of finite element model is tested to be feasible by comparing the numerical load-displacement hysteretic curves and their skeleton curves with the experimental ones. Further studies are carried out through changing models’ FRP (GFRP/CFRP) thickness, axial compression ratio and cross sectional steel ratio. Simulation results show that specimens with thicker FRP (GFRP/CFRP) equip better energy dissipation capacity and higher bearing capacity. In elastic-plastic stage the stiffness of specimen degradation becomes more serious as axial compression increases. Energy dissipation capacity is enhanced as cross sectional steel ratio increases.
Studies on Design Plan Optimized Evaluation Method of Old Industrial Building Regeneration Utilization Project
Authors: Yan Rui Qi , Li Hui Min , Chen Xu , Tian Wei
Published: October 2011

Until now, there have been no reasonable methods for optimizing the design plan of old industrial building regeneration utilization project.Aiming to the self-characteristics of the old industrial regeneration utilization project, the application deficiency of the regular analytic hierarch process existing in the project is going to be researched, as is improved from the analysis process, consistency check and weight confirm in order to make the design plan of the old industrial building regeneration utilization project scientific and reasonable.
The Survey and Prevention of Bridges and Culverts Flood Hazard in the Eastern Mountainous Areas of Jilin Province
Authors: Wang Wen Hua , Zhao Wen Ding
Published: October 2011

The catastrophic floods in Jilin province on July 28th 2010 led to the serious multiple bridges and culverts flood hazards in the roads in eastern mountainous area, and brought about the inestimable economic losses. In order to effectively strengthen prevention and set up the reasonable measures of management bridges and culverts flood hazard, on the basis of the survey of bridges and culverts flood hazard along the road, we analysed the reason of it. After that we put forward the measures of the prevention and cure, which including the measures of the design, construction, management, maintenance etc. Based on the above survey of the bridges and culverts flood hazard, we found that its prevention and cure should find the main reason of causing bridges and culverts flood hazard, make the prevention coming first, pay various attention to bridges and culverts flood hazard, its occurrence can get effective control.
The Anti-Seismic Analysis of the Lock-up Device on the Arch Bridge
Authors: Kong Ling Jun , Chen Yan Bei , Li Peng , Jiang Qi Bin
Published: October 2011

To study the anti-seismic performance of Lock-up device, the two computational models which are respectively uninstalled Lock-up device and installed Lock-up device on the arch bridge are established. Nonlinear time-history analyses are carried out by the Midas/Civil software in this paper. The interaction between pile and soil is considered in the analyses. The results show that the maximum shear forces of the tops and the maximum bending moments of the bottoms of all piers are quite uniform after the LUD are installed and that the displacements of the top of the fixed pier has been decreased.
Seismic Response Analysis of a High-Rise Tower with Complex Structure
Authors: Bao Li Yuan , Su San Qing , Hou Jun Feng , Guo Huan
Published: October 2011

The complex tower structure appears as modeling of palms together, which is designed as steel frame-core tube structure. This paper uses SAP2000 to analysis seismic response respectively on the linear and elastic-plastic stage, and puts forward some specific suggestions for seismic design according to the analysis and calculation.
The Construction Process Simulation of a Large-Span Rhombic Space Truss Using FEM Analysis
Authors: Yan Xu , Li Tie Ying , Nie Yun Jing
Published: October 2011

With the developments of the design theories and the researches, the quantity and the technology of space truss systems in our country have reached the international leading level. In the meantime, the construction methods need to achieve even higher standard. In the article, the rhombic space truss roof of the north station building of Suzhou is selected as the research object. Each step of the sliding and unloading construction is simulated by FEM. The stability and rigidity of the truss are checked in detail. It gives an representative exsample for complicated construction design of large-span space trusses.
Complex with Dangerous Rock Engineering Geological Characteristics and their Reinforcement Technology Research
Authors: Xiao Jin
Published: October 2011

In the southwest mountains, a lot of dangerous rock bands are widely distributed, whose formation conditions are complex, which are diverse, specially located and dangerous. How to reinforce such complex unstable rock band In this paper, the treatment of typical dangerous rock band is taken as an example, the classification investigation and one by one evaluation is performed first, and then each block composing the complex and dangerous rock band is analyzed and calculated. According to the site conditions and calculated results of each block composing the dangerous rock, using clearing risk - repairing - reinforcement- landscaping and other technology portfolio approach, forming a comprehensive treatment program to conduct a thorough treatment for each dangerous rock, it is proved that such a reinforcement technique has good effects with the management of dangerous rock.
The Study of Axial Compression Ratio Impact on Steel Reinforced Concrete Pressure Twist Component
Authors: Liu Ji Ming , Xing Xiang Yang , Liu Zeng Wei
Published: October 2011

As Steel reinforced concrete (SRC) structure has a good prospect in Practical engineering, large number of studies carried out home and abroad, as for the study of the Steel reinforced concrete composite torsion , research data is not mature at present time. This paper analyzed the steel reinforced concrete members’ Torsion properties under combined force by method of the finite element analysis. Considering the main affecting factors like compression ratio to reveal the SRC structures under the force of monotonic torque’s characteristics of the damage and capacity, etc.
Prediction of the Ground Settlements Induced by Shallow-Buried Subway Tunneling in the Loess Region
Authors: Han Dong , Su San Qing , Yang Yu
Published: October 2011

Stochastic medium theory is applied in the research of the ground settlements Induced by subway tunneling lately. There are a lot of simplification and many difference between the predict results and the engineering practice in the prediction process in irregular tunneling. This paper gives expression of the ground settlements Induced by any section tunneling using standard transform principle on the base of the correctional stochastic medium theory. On the basis of above discussion, proving this method is effective and reliable by the verification.
Research on Organization Structure Adaptability of Real Estate Enterprise Based on Analytical Hierarchy Process and Grey System Theory
Authors: Li Qian , Chen Run Qiang , Bai Rong
Published: October 2011

In our real estate enterprises, the rapid growth and lopsided organization structure have become the obstacle for the development. This paper regards real estate enterprise as the research object. Based on the foundation of substantive investigation and expert consultation，considering the practical situation of real estate enterprise, following the basic principles of index system design of organization structure adaptability evaluation, this paper constructs an index system of organization structure adaptability of real estate enterprise evaluation. Combining AHP, Grey System Theory and concrete examples, this paper works out the evaluation grade of organization structure adaptability of real estate enterprise.
Performances Analysis of Tall Concrete Frames on the Ground Fissure Field
Authors: Fu Guang Yao , Zeng Fan Sheng , Tian Min , Zhou Yang Yang
Published: October 2011

Through predict activities trend of ground fissures, given to the ground surface subsidence curve on the topper side in the next 50 years. Established a tall concrete frame construction model, using SAP2000 finite element programs, take a distance of the building depart from the fissure as analytical variables, in considering the dead load, live load, horizontal seismic action and combine with foundation differential settlement working conditions, analyze the elastic displacement and internal forces of the structure. The results showed that，in the topper side area near to the fissure, affected by the avoidance distance, the displacements and internal forces of the frame structure change remarkably. The growth and redistribution of internal forces performance are the most serious in the building base floor of framework， the internal forces change in ends of both beam and column will cause a change in the direction of bending moment， but also an inflection point of the column will change with the internal forces growth and regression.
On the Real Estate Project Cost Management
Authors: Liu Shu Ru , Li Min Juan
Published: October 2011

Real estate Industry is capital-intensive. Cost management is very important for real estate. Efficient cost management is one of important means that can ensure sustainable development of the real estate business. Now, we must find out the efficient cost management means according to analysis the importance of the real estate and the problem exist in it.
Study on Improvement for Seismic Behavior of Reinforced Concrete Shear Walls
Authors: Chu Ming Jin , Feng Peng , Ye Lie Ping
Published: October 2011

Shear walls are commonly used as structural elements to resist earthquake. The seismic performance of shear wall can be guaranteed under small earthquakes, but problems exist when it is subjected to large earthquakes. To improve the ductility and energy dissipation capacity of shear walls in large earthquakes, shear failure must be avoided and the performance of plastic hinge region must be improved. The adaptive-slit shear walls (ASSW) is proposed in this paper The mechanical characteristics of ASSW satisfy the requirements of structures under different seismic level. Therefore the damage process of ASSW can be controlled and the ductile shear failure can be realized, which obviously improve the seismic performance of shear wall structures.
Numerical Derivation of Pressure-Impulse Diagrams for Unreinforced Brick Masonry Walls
Authors: Wei Xue Ying , Huang Tuo , Li Nan
Published: October 2011

Pressure-impulse diagrams have been extensively used for damage assessments of structural components subject to a specified blast loading. In this paper, a numerical method is used to generate pressure-impulse diagrams for unreinforced masonry walls subjected to blast loading. A previously developed plastic damage material model accounting for strain rate effects is used for brick and mortar. Three levels of damage criteria are defined based on maximum deflection of the wall and rotation of the supports. The obtained blast response for unreinforced masonry walls are validated against field test data. It is shown that the obtained pressure-impulse diagrams have an improved ability to evaluate the damage level of masonry walls.
Analysis of Wall Rock Settlement on Section of Super Shallow Four-Arch Tunnel
Authors: Huo Run Ke , Yao Yong Zhen , Yue Qi Xian
Published: October 2011

With the development of subway in major cities, the density of underground railway tunnel increases. At the same time, the form and the area of subway tunnel become different. All these make higher requirements for stability of wall rock. The super section shallow multi-arch tunnel between Hananzhan Station and Nongkeyuan Station of Harbin subway ,with the twin-side heading tunnel construction method do harm to the wall rock for many times. It becomes more difficult for below the main road. This paper, using finite element analysis ANSYS software to simulate the excavation process, obtains rock settlement of the four-arch tunnel through on-site monitoring data, and further validates the feasibility of the twin-side heading tunnel construction method.
Research of Two-Series-Mass Dynamic Vibration Absorber and it’s Application on Building Vibration Control
Authors: Pan Gong Yu , Zhang Ying
Published: October 2011

Multiplexing the dynamic vibration absorber (DVA) has tried for improving the vibration absorption efficiency of the dynamic vibration absorber, and because there are several tuning vibration frequencies in the multi-mass dynamic vibration absorber system, the vibration absorption efficiency is more excellent than a conventional single-mass dynamic vibration absorber when they are in the same total mass ratio. In this paper, a two-series-mass dynamic vibration absorber was proposed, optimal parameters of the two-series-mass dynamic vibration absorber have been calculated and vibration absorption is analyzed with the simulation and experiment. The results show that the two-series-mss dynamic vibration absorber can improve vibration absorption, in the same total mass ratio, by about 20% above that of a conventional single-mass dynamic vibration absorber. Based on the above optimal results, the two-series-mass dynamic vibration was used for vibration control on high building, and the practical measure result shows its effectiveness.
Behaviors of Masonry Building with Frame Structure in Earthquake
Authors: Liu Xiao Yu , Xu Xiao Tong , Zhao Zhan Chao
Published: October 2011

Masonry building with frame structure (hereinafter referred to as MBFS), rigid upper and flexible lower, is a special kind of structure appropriate for Chinese economic conditions in current years. Although this kind of structure is proven unstable in earthquake, its significant functional advantages and economic competitiveness make it popular in roadside buildings in small cities. In recent years, MBFS damaged seriously in earthquakes. This paper expounds different models and reasons of seismic damage of this kind of structures. This paper also discusses measures to reduce seismic damage of such structure. In the end, this paper proposes an ideal failure model of MBFS after analyzing the essence of damage. The ideals in this paper can help engineers reducing the seismic damage of MBFS as much as possible.
Resistance Analysis of Reinforced Concrete Structures in Construction
Authors: Zhao Nan , Yan Wen
Published: October 2011

This paper analyses the characteristics of resistance of structural components, puts forward the concept of early resistance force of structural components, and discuss the main factors which affect it based on the field measurement investigation and theoretical analysis. Besides, in the paper the reduction factor is applied to reflect time-varying features of early-age concrete strength, and utilization coefficient of concrete strength is utilized to present the influence of early time-varying features of cohesive action on resistance. The paper finally deduces the formula of early-age resistance force of typical flexural member, and gives the time-changing law of early resistance by using a case.
Numerical Analysis of Interlaminar Stress Distributions around Hole in Thermoplastic Laminate
Authors: Zhao Guo Hua , Shu Qing Lian , Huang Bo Sheng
Published: October 2011

This paper investigates the interlaminar stress distributions at hole edge of notched thermoplastic laminates. Two numerical models of AS4/PEEK laminates with configuration of [±25]S4 and [0/±45/90]2S were built and studied by finite element code ANSYS. The results show: (1) The angle-ply configuration ([±25]S4) may cause more severe concentration of interlaminar shear stress at hole edge; (2) the quasi-isotropic configuration ([0/±45/90]2S) can lessen the stress concentration at hole edge.
Research on Constitutive Law of UHPFRC Used in Numerical Simulation
Authors: Guo Yi Hong , Wang Zhen Qing
Published: October 2011

This paper presents compressive and tensile constitutive law of UHPFRC used in numerical simulation. UHPFRC exhibits different constitutive law from normal and high strength concrete. A multi-directional fixed crack criterion that considers tensile strain hardening is defined to describe tensile behavior, and Drucker-Prager criterion with an associate d flow rule is adopted in the compressive region. The comparison of numerical results with experimental results indicates a good agreement.
Experimental Studies on Bearing Capacity of Post-Tensioned Unbonded Prestressed Concrete Hollowed Floors
Authors: Yang Xiao Hua , Zhou Chao Yang , He Xue Jun , Yang Zhi Qing
Published: October 2011

A 1/4 scales four-storey model of post-tensioned unbonded prestressed concrete hollow slab-column structure has been made to do the ultimate load test on the second-storey floor. By measuring the floor deflection, stresses of steel bars and cracks of floors, the bearing capacity of floor is explored. The bearing capacity tests of floor are divided into three stages: elastic stage, crack growth stage and destruction stage. Based on the test results and crack developments in floor, a improved plastic hinge model is carried out to predict the ultimate loads. The calculated results of the ultimate loads with improved plastic hinge model are in good agreement with the experiment data.
System Reliability Study Based on Bearing Capacity Update and Deformation Iteration
Authors: Zhu Hao Liang , Sun Wen Bo
Published: October 2011

For the sensitive of distribution parameters of random variables, system reliability research should be focus on identifying the significant failure modes, while failure probability as a quantitative reference index, only combining both of them can better estimate system reliability. On the basis of load incremental step theory, a method for identifying the significant failure modes which could more accurately simulate the real failure process for considering the change of bearing capacity and spatial position is proposed in this paper. Then, the corresponding program is prepared with APDL on ANSYS platform. On the one hand, the efficiency and accuracy of identification is improved, on the other hand, the usefulness of this method is enhanced. Finally, the reliability of a space grid engineering project is analyzed and discussed by this method; moreover, the system reliability index β is calculated as well. These analysis results are helpful to provide scientific basis for structural optimization, structural testing, and structural reinforcement and so on.
Safety Analysis on the Variable Constraint Space Reticulated Shell Structures
Authors: Wang Xiu Li , Jin En Ping , Zhu Yan Peng
Published: October 2011

During construction, the spatial shell structure is the variable constraint structure system. In order to guarantee the construction quality and safety, its addition or disassembly scheme of temporary support must be optimized design. Based on variable constraint structure analysis method, the paper simulated and analyzed possible multiple variable constraint scheme during the long-span space reticulated shell structural construction, and put forward the principle and method abide by addition and disassembly design of temporary support. For other variable constraint structures similar to the spatial shells, the principle and method proposed has a very great reference value.
Study on Stability of High Embankments on Rock Slope under Complicated Stress Conditions
Authors: Ding Gui Ling
Published: October 2011

Three-dimensional finite element analysis should be used in stability analysis of slope because it can overcome the short advantages of two-dimensional finite element and can simulate the complex topographic and geological conditions. Based on the large-scale triaxial shear test, the modified Duncan-Chang model is established. Based on strength reduction elasto-plastic finite element, stability of high fill embankment was studied with three-dimensional finite element method considering the complex terrain conditions. Study results suggest that plastic strain and displacement mutant of slip surface node can be a sign of slope instability as a whole. At the same time calculation of three-dimensional finite element also does not converge. Therefore, it can be slope instability criterion calculate whether the finite element static analysis converges or not. On the other hand, stability safety factor of high fill embankment under three-dimensional conditions is larger than that of two-dimensional conditions, which shows that boundary conditions of high fill embankment enhance its stability.
A New Framework of Urban and Rural Planning System in Guangdong
Authors: Qi Dong Jin , Zhou Jian Yun
Published: October 2011

As the "Urban and Rural Planning Law " had been promulgated in 2008, the paper studied the context of socio-economic development and the actual situation of urban and rural development in Guangdong Province, drawing on the experience of the British planning system, proposing the framework of urban and rural planning system as "Provincial Spatial Plan" and "Local Development Plan", which including urban system planning, master plan, detailed plan, village plan four types. The new framework will streamline the planning system, reduce the levels of planning and clear the relationship between different types of planning, contributing to regional coordination in urban and rural areas.
Fuzzy Ideal Points Method In Project Construction Sequence of the Downstream of Yellow River
Authors: Zhou Zhen Min
Published: October 2011

Based on the project construction and investment feature of the Downstream of Yellow River, the structures were divided into flood control dike, water diversion, irrigation and water saving, soil erosion conservation and ecological projects, river mouth management and development and water resources information. Using fuzzy and decision making analysis theory and project planning investigation data, the different project weights were calculated and fuzzy ideal point model was set up. According to administrative region, the total area of the downstream of the Yellow River was divided as 14 sub-regions. Using the model to solve the project construction sequence, the sequence scheme of the water project construction was achieved. The results have an important significance for the different water projects construction of the downstream of the Yellow River.
The Invalidity Analyse on Feasibility of Urban Color Planning
Authors: Wang Xia , Huang Lei
Published: October 2011

As one of the most effective ways to create the urban scene, urban color planning was once a hot spot in the planning industry in the past years. However, the implementation of the planning always ended up with nothing or fails to come up to the expectation. This paper analyzes profoundly the reasons for the failure of current urban color planning in our country, and puts forward several aspects to be focused for the practical urban color planning from nature of the urban color and complexity of the problems existed in the urban color planning.
The Application of GIS-SCENARIO Decision Method in Spatial Planning
Authors: Wu Yi Zhou , Wu Ling Lin
Published: October 2011

This study puts forward the framework of GIS—Scenario decision method and introduces some methods, ideas, principles and analysis process applied in regional spatial planning. Combining the GIS spatial analysis method with the scenario—planning, simulating and contrasting scenarios for regional key development zones, this study determines regional development strategies. Findings show that the GIS-SCENARIO analysis method can quantitatively analyze factors influencing the spatial distribution more accurately. Considering fully complex real situation and combined with reasonable value judgments, the GIS can provide various factors with a spatial analysis platform to contact and contrast with each other. As a strategic planning approach, it enables decision makers decide relatively reasonably in an uncertain and unpredictable situation and improves rationality in planning.
Innovation Request and Technical Method of Urban Geography in the New Period
Authors: Zheng Wen Hui
Published: October 2011

Urban geography is widely used in urban planning, regional planning, and multiform strategy researches about urban and area development. In the new period, urban geography is facing omnifarious innovation request in china. Firstly, the paper indicates that many problems such as lack of concept, disordered definition in basic concepts of urban geography in China; it is important to define basic concepts of urban areas to enhance pertinence and rationality of region research and region policy. Late-development countries have not duplicated the typical urbanized regional model of developed countries, which reveal urban geography possesses broad research prospect and opportunity in the countries whose economy and society reform rapidly. Under globalization, researcher should attach importance to singularity of the subjects and perspectiveness of research conclusions. Then, through introduction of research development, the paper discusses application of technical method in urban geography from angles of constitution of urban development strategy, quantification, facility location and geocomputation. Furthermore, through research development of business center, the paper expounds the significance of combining speculative knowledge with technical method. Finally, the paper summarizes the enlightenments which are beneficial to urban geography research.
Experimental Research on Seismic Behavior of Exterior Frame Joints with T-Shaped CFST Column and Steel Beam
Authors: Du Guo Feng , Ma Chao , Xu Cheng Xiang
Published: October 2011

In order to understand the mechanical performance and related tectonic design requirements of the concrete-filled steel tubular joints with special-shaped cross-section , three T-shaped concrete filled steel tubular column joints with exterior diaphragms were manufactured and experimented under cyclic loading. By changing the axial compression ratio of the columns and increasing the width and overhanging length of the stiffening ring, the hysteretic performance and working mechanism of such joints under cyclic loading were studied. The results show that by increasing the width and overhanging length of the stiffening ring, the hysteretic performance, ductility and energy dissipation capacity of joints were obviously improved.