bluuebunny/crossref_metadata_2025 huggingface dataset:
Moisture Absorption of Laminated Bamboo Composite and its Influence on Mechanical Properties
Authors: Yu Zi Xuan , Jiang Ze Hui , Wang Ge
Published: October 2012

Laminated bamboo composite (LBC) has received a great attention due to its environmental friendly characteristics and excellent physical and mechanical properties, therefore it is necessary to investigate the durability of the LBC material in ambient environment (temperature and relative humidity). In this paper, firstly, LBC materials were manufactured in laboratory. Moisture absorption and thickness swelling kinetics of the materials at different temperatures and relative humidity were investigated. Then effects of ambient environment on mechanical properties were evaluated at three different ambient temperatures (21 °C, 36 °C, and 60 °C) and different moisture contents. It is found that the moisture absorption and the thickness swelling increase with temperature, relative humidity and ageing time before an equilibrium condition is satisfied. Parameters of the diffusion coefficient and the swelling rate increase with the temperature. In addition, there is a significant decrease in mechanical properties of the moisture-saturated specimens compared to the dry ones. And the degradation of the bending property and the compressive strength is found to be a function of the moisture absorption during the initial period and becomes stable as the absorption process approaches equilibrium. Finally, surface erosions are shown by scanning electron microscopy (SEM) after the hydrothermal aging at 60 °C.
Dielectric Properties of Sol-Gel Prepared Ni-Doped CaCu3Ti4O12 Ceramics
Authors: Jiao Lei , Li Hui , Yang Yan Wei , Wang Tian Ping
Published: October 2012

Dielectric properties of sol–gel prepared Ni-doped calcium copper titanate Ceramics (CCNTO) are investigated. For the x of CaCu3NixTi4O12+x is 0, 0.1, 0.2, 0.3 respectively. The XRD pattern shows that crystal structure of the sample without Ni is basically single-phase. The dielectric properties of CCNTO were analyzed by Agilent 4294A. The experimental results show that the sample has a better dielectric properties when x=0.2. The maximum dielectric constants is found when x=0.2. The dielectric loss decreased with the increases of Ni in the low frequency region, the high frequency region is just the opposite, the sample has lower dielectric loss in the low frequency region when x=0.2.
Effect of Slate Powder on Mineral Admixtures in Suppressing Alkali-Silica Reaction of Slate Aggregate
Authors: Peng Xian Xiao , Li Gu Hua , Huang Wu , Li Yuan Fu , He Xiao Chun
Published: October 2012

In order to study the effects of slate powder on mineral admixtures in suppressing ASR of slate aggregate, refer to the following methods: accelerated mortar bar test in “Standard for Constructional Quality Acceptance of Railway Concrete Engineering” TB10424-2010 and “Durability Design of Railway Concrete Structures” TB10005-2010, as well as an improved steam curing method. The text has studied the expansion of the specimens that are made from slate aggregate with different powder contents and specimens using slate powder as admixtures. The results show : When powder content in aggregate is less than 20%, it dose not have adverse effects; ASR of high-activity slate aggregate can be suppressed by using 30% fly ash and 5% silica fume as mineral admixtures; when the mineral admixtures are effective, a certain amount of powder mixed with admixtures can contribute to suppression; the main mechanism that slate powder can suppress ASR is that alkali in concrete can be consumed and physically diluted by slate powder.
Thermodynamic Analysis of Biomass and Natural Gas Combined Cooling Heating and Power System
Authors: Jing You Yin , Chen Tuo Fa , Wang Jiang Jiang , Zhao Hong Lei
Published: October 2012

This paper presents a biomass and natural gas combined cooling heating and power (BNGCCHP) system, which achieves energy cascade utilization and improves overall energy efficiency. The thermodynamic analysis of BNCCHP system is analyzed from the energy and exergy balance respectively. A case of BNCCHP system for a commercial building is studied.
Numerical Study on Heat and Mass Transfer of Plate Falling Film Absorber with Wire-Meshed Fins
Authors: Zhang Jing Jing , Zhao Dan Dan , Wan Lu Chun , Zhang Bao Huai , Chen Ya Ping
Published: October 2012

A mathematical model of heat and mass transfer process in plate falling film absorber with wire-meshed fins was developed. The model could predict temperature and concentration distribution as well as the solution side heat transfer coefficient and the absorption rate. The results verify that heat and mass transfer performance of the plate falling film absorber with wire-meshed fins is better than the past absorber. Compared with the plate falling film absorber without fins, heat transfer coefficient of the absorber in this article increases 1.06 times and the absorption rate increases 2.32 times.
A Laboratory Study of Stratified Characteristics of Cohesive Sediment Movement in the Lower Energy Conditions
Authors: Wang Jia Sheng , Chai Xiao Ling , Chen Li
Published: October 2012

Cohesive sediment is a major component of clay. Its erosion and movement has a significant impact on the soil environment. Moreover, cohesive sediment is an important part of the sediment of lakes and oceans, and its movement and transportation also have a crucial influence over dispersion of pollutants in water. Open channel flume experiments were carried out to study the characteristics of cohesive sediment movement; simultaneously the velocity and sediment concentration vertical profile was investigated. The experimental results indicate that under the conditions of suitable hydrodynamic velocity and sediment concentration, a special-shaped sediment flow, stratified movement, takes place in the flume. Its formation and features are closely related to fluid parameters and sediment concentration. Its velocity distribution shows a V-shaped pattern falling forward. At the corner of V, the maximum velocity is vertically located in the middle of the flume. The concentration distribution is vertically stratified into three discrete layers on whose interfaces the concentrations change suddenly. To form lamination movement, different hydrodynamic conditions are required under different sediment concentrations. When the concentration increases, the corresponding flow intensity also increases.
Design and Research on One Avoiding-Clogging Equipment in Untreated Sewage Heat Pump Air Conditioning System
Authors: Liu Zhi Bin , Zhang Ji Li , Ma Liang Dong
Published: October 2012

Appling urban untreated sewage as a cool and heat source of the heat pump air conditioning system is considered to be an effective way to develop urban sewage resource and a critical technique to serve the building energy system.Applications of technical difficulties are to solve the jam on sewage dirt to tube of heat exchanger and pipes. The multi-filter surface backwash technology is used to separate the suspended solids from the sewage and clean the dirt on the grille. By describing the filtration technique in the sewage source heat pump system to introduce the principle of operation and control process of the multi-filter surface backwash technology. By using in commercialese, the technology is proved to be feasible and reliability. These methods could serve as a reference for designing and application untreated sewage source heat pump systems.
The Triple-Shear Unified Analytical Solution of Stress and Displacement of Softening Material Thick Walled Cylinder
Authors: Ma Jing Huai
Published: October 2012

Based on the further analysis to triple-shear unified yield criterion, the Lode parameter expression of the triple-shear unified yield criterion were given. This paper performs the analysis computation to softening material thick-walled cylinder under internal pressure based on triple-shear unified yield criterion. The analytical solution of stress and displacement is obtained. By using triple-shear unified yield criterion, more reasonable solution for different softening material can be derived.
Asymptotic Stability for an Impulsive Model of Hematopoiesis with Time Delay
Authors: Chen Rui , Ju Pei Jun
Published: October 2012

A model of hematopoiesis with time delay and impulses is studied. Based on the Lyapunov function method, uniform stability and uniform asymptotic stability of the equilibria is discussed.
Damping of Stay Cable-Passive Damper System with Effects of Cable Bending Stiffness and Damper Stiffness
Authors: Liu Min , Zhang Guang Qiao
Published: October 2012

In the present paper, the asymptotic solution of modal damping ratio of stay cable-passive damper system with the influence of cable bending stiffness and damper stiffness was derived. Maximum modal damping ratio and corresponding optimal damping coefficient, which indicated the relationships of the characteristics of the damper and the cable bending stiffness was theoretically analyzed to obtain their close solutions. On the basis of these close solutions, numerical analysis of modal damping of stay cable-passive damper system with the effects of cable bending stiffness and damper stiffness was conducted. The numerical and analytical results show that the maximum modal damping ratio decrease and the corresponding damping coefficient increase, when considering the influence of the damper stiffness and the cable bending stiffness.
Dynamic Design Height of Embankment Preloading Soil in Dongting Lake District
Authors: Li You Yun , Yi Zhen , Liang Zhong Shan
Published: October 2012

A new computational method of preloading the earthwork has been proposed in this paper. Firstly, the various factors affecting the computed method for the foundation of the average degree of consolidation have been analyzed. Secondly, the settlement prediction method has been described according to the settlement to calculate the degree of consolidation. Then the consolidation coefficient has been calculated according to the least square method. The computed algorithm compute the preloading height based on the Takagi Shunsuke method and the measured data is presented. Finally, two examples illustrate the validity and the feasibility of the computed method in this paper.
Dynamics in a Van Der Pol Model with Delay
Authors: Xu Chang Jin , Li Pei Luan , Yao Ling Yun
Published: October 2012

In this paper, the dynamics of a van der pol model with delay are considered. It is shown that the asymptotic behavior depends crucially on the time delay parameter. By regarded the delay as a bifurcation parameter, we are particularly interested in the study of the Hopf bifurcation problem. The length of delay which preserves the stability of the equilibrium is calculated. Some numerical simulations for justifying the analytical findings are included.
Experimental Studies on the Effects of Nozzle Structures on Characteristics of Submerged Gas Jet Noise
Authors: Hao Zong Rui , Zhou Zhong Hai
Published: October 2012

The structures of nozzle outlet have great effects on jet noise generated by submerged gas jet. Five nozzles with different cross-sections were designed to study the influences of nozzle structures on sound levels by experimental methods. The flow characteristics and sound pressure levels were measured and the gas-liquid flows formed by submerged gas jets under different Weber numbers were also observed. The results show that the gas-liquid flows transformed from bubbling regime to jetting regime with the increase of Weber numbers. With respect to bubbling flow, no significant differences in sound levels for different nozzles were found. However, a remarkable increase of acoustic emission was caused by the transformation of flow patterns over the frequency bands of 0.6-4 kHz for all nozzles. In addition, sound pressure levels for elliptical nozzle were much lower than those of other nozzles over the frequency bands of 0.6-4 kHz. Therefore, it would be a reasonable strategy to adopt several elliptical orifices instead of round nozzle to reduce the gas jet noise in the design of underwater exhaust muffler.
Adaptive Moving Mesh Finite Element Method for Space Fractional Advection Dispersion Equation
Authors: Zhou Zhi Qiang , Wu Hong Ying
Published: October 2012

Space fractional advection dispersion equation includes non-local differential operators, which leads to calculating numerical integrals with weakly singular kernel on every subintervals. Oscillations are visible in computed solutions when fractional order tends to 1. Studies show that the stiffness matrix of time semi-discretization can be calculated directly by formulas established from a special variational formulation. Oscillations are eliminated by using adaptive moving mesh and De Boor algorithm, while the number of nodes remains unchanged.
The Influence of Chord Yield-to-Tensile Stress Ratio on the Static Strength of Unstiffened CHS K-Gap Joints under Static Axial Loading
Authors: Kaluba Chisanga , Tawana M. Mulife
Published: October 2012

The yield strength-to-tensile stress ratio (fy/fu) is considered to be an important material factor in the design of welded tubular joints. For instance CIDECT (2008) has set a limitation on fy of 0.8fu and for steels with nominal fy greater than 355Mpa and a reduction factor of 0.9 on all joint strength formulae to account for the relatively larger deformations that take place for joints with nominal fy of 450Mpa[1]. In this study a statistical analysis of an experimental database was carried in order to determine the influence of the chord fy/fu ratio on joint strength. A finite element study was also carried out in order to quantify this influence and a yield strength function was proposed. Results from the statistical analysis and finite element study both show that the static strength of unstiffened circular hollow section (CHS) K-gap joints under static axial loading is inversely proportional to the chord fy/fu ratio.
Oscillation Criterion of Third-Order Nonlinear Neutral Damped Functional Differential Equations
Authors: Zeng Yun Hui
Published: October 2012

In this paper, A class of third-order nonlinear neutral damped functional differential equations with distributed deviating arguments are studied. By using a generalized Riccati transformation and Kamenev-type or Philos-type integral averaging technique,we establish some new sufficient conditions which insure that any solution of this equation oscillates or converges to zero.
A New Construction Method for Web-Based Large-Scale 3D Terrain Model
Authors: Li Zhen Pei , Wang Ze Gen , Jia Hong Liang
Published: October 2012

With the development of network and information technology, it is highly desirable to create 3D geoscience applications in the network environment. However, construction of web-based 3D terrain model is one of the foundation works of 3D geoscience applications in the network environment. This paper presents a new method of constructing large-scale 3D terrain model based on Extensible 3D (X3D). In this way, we first use Geospatial components of X3D to build 3D terrain model by using DEM as the data source, then we publish the 3D terrain model to the internet with a architecture of Brower/Server and plug-in technology. To promote the display performance of large-scale 3D terrain model, We presents an approach that using the Level of Detail (LOD) technology to simplify the 3D terrain model. The application results show that the method this paper presented has advantage of easy to integrate with other network system, thereby easy to realize data sharing and interoperation; the method also has virtues of fast display speed, high ability of interaction. It’s an effective method for constructing large-scale 3D terrain model in network environment.
Reliability Model of Series and Parallel Systems under Imperfect Information
Authors: Suo Bin , Zeng Chao , Cheng Yong Sheng , Li Jun
Published: October 2012

In the situation that unit failure probability is imprecise when calculation the failure probability of system, classical probability method is not applicable, and the analysis result of interval method is coarse. To calculate the reliability of series and parallel systems in above situation, D-S evidence theory was used to represent the unit failure probability. Multi-sources information was fused, and belief and plausibility function were used to calculate the reliability of series and parallel systems by evidential reasoning. By this mean, lower and upper bounds of probability distribution of system failure probability were obtained. Simulation result shows that the proposed method is preferable to deal with the imprecise probability in reliability calculation, and can get additional information when compare with interval analysis method.
Application of Virtual Reality Technology for Emergency Evacuation in High-Rise Buildings
Authors: Zhang Jun Fang , Wang Shu Ping
Published: October 2012

A virtual reality system was developed to simulate emergency evacuations during fires. The spreading of the flame and smoke in the virtual fire was modeled based on numerical fire simulations, so that the conditions are similar to real life. The paper investigates a number of evacuation strategies in high-rise buildings and the set of human factors affecting high-rise evacuations. It also discusses the challenges that building occupants and fire departments face during a fire emergency.
Sensitivity of B-Splines Weight Function Neural Networks and its Application on Signal Recognition
Authors: Zhang Dai Yuan
Published: October 2012

The statistical sensitivity of training neural networks by B-splines weight functions and its applications for digital modulation signal recognition (DMSR) is discussed in this paper. By extracting some instantaneous parameters using the technology of DMSR, and using the sensitivity formula of B-splines weight function neural networks proposed in this paper, we show that the classifier of B-splines weight function neural networks has optimized architecture and high recognition rate.
Numerical Test Study on the Mechanical Behavior of Rock Creep Fracture
Authors: Yuan Hai Ping , Zhu Li Gang , Zhai You Jing , Chen Shui Mei
Published: October 2012

The mechanical behavior of rock interior creep fracture evolution and the state are difficult to observe. Combined with the laboratory rock compressive-creep test, the uniaxial creep numerical test based on FLAC3D was carried out. The different positions of the model displacement, stress, strain and damage zone were analyzed under different loading. The mechanical behavior of evolution process and characteristics of rock creep fracture were revealed under the different loading. The results show that: the data of numerical simulation and laboratory test are identical by comparing with laboratory test, and numerical test on simulated rock creep mechanical behavior evolution and methods is feasible and effective. It is a new method that can improve laboratory test of the microscopic creep, provide basis for evaluation of engineering rock mass stability too.
Experimental Study on Moisture Migration in Unsaturated Loess under Freezing Effect
Authors: Wang Tie Hang , Zhang Hui , Lu Xing She
Published: October 2012

Test equipments were designed and manufactured for producing moisture migration in unsaturated loess under freezing effect. The results showed that both the amount of freezing-thawing cycles and initial water content of soil samples affect the process of moisture migration. As the freezing front advanced in the sample, the water content in the unfrozen part significantly reduced and the water content in the freezing part significantly increased, with the maximum water content at the freezing front. Comparing to the moisture migration in the unfrozen part, the moisture migration to the freezing front in the freezing part was relatively slow. For soil samples with higher initial water content, the increment of water content at the freezing front was higher and sometimes ice could be formed. During a certain amount of freezing-thawing cycles, the water content at the freezing front kept increasing. However, as the amount of freezing-thawing cycles continued increasing, the freezing front started to move to the part with negative temperature and the maximum water content appears at the end with the lowest temperature.
An Investigation into Nonlinearity of Foundation Soil of Gravity Retaining Wall Based on an Inversion Method
Authors: Xi Hong Yan , Zhang Jun Hua , Sun Jing , Li Jing , Wang You Qing , Chen Xian Mai , Wang Fu Tong
Published: October 2012

Strong earthquake ground motion leads to residual displacements of gravity retaining walls. Since large deformation occurs in foundation soil, nonlinear mechanical behavior should not be neglected in numerical modeling. The inversion methodology in geophysics is borrowed here to study the nonlinearity, i.e. the variation of shear modulus and damping ratio with the increase of shear strain of soil. A simplified model for the seismic displacement of retaining walls is combined with a genetic algorithm for the inversion. The dynamic shear modulus and damping ratio curves, representing the nonlinear property of foundation soil in a centrifuge test for gravity retaining walls, is obtained by the use of an inversion scheme. The result indicates that, for low level of shear strain, the shear modulus is larger than that used in the literature, implying that the model ground may be stiffer than expectation. For high level of shear strain, the inverted damping ratio is larger than the conventional one, which has efficiently suppressed an overestimation of seismic displacements. It is also displayed that the inversion method is an effective way to obtain quantitatively the dynamic nonlinearity of foundation soil of gravity retaining walls.
Numerical Simulation on Vertical Earth Pressure Distribution for Culverts under High Fills
Authors: Fan He , Ning Bao Kuan , Gong Lei
Published: October 2012

High fill culverts have been widely used in expressway in mountain area and problems of culverts frequently take place because of improper design including some earth-pressure calculated values conservatively or culvert type selection irrationally. FEM numerical simulation was carried out to investigate the stress state of the culvert fill. The effect of four influences on the stress state of high-filled culvert is discussed. The research results show that culvert structure type influences earth pressure distribution that arch culvert is different to slab and box culvert. Earth pressure values when boundary slope is 1:0.35 are all larger than slope 1:0. Due to arch effect and stress distributed secondly, nonlinear increased amplitude of earth pressure is reduced with fill heightening. Earth pressure of culvert top and side decreased along with culvert side wall thickness increment. The research can give some references on the design correctly.
The Experiment Study on Thermal Conductivity of Loess-Like Soil
Authors: Guo Liang Liang , Mei Zhen Zhou , Zhou Bing Qiang
Published: October 2012

The author measured the TC of losses-like soil in Changchun with QTM-D2 and discussed the effect of samples in different sizes, the testing error in lab and in site. The research about the size error of TC offered feasible solution to measure TC of geotechnical materials in site. In addition, the empirical relations between TC and temperature of sand and loess-like soil, and their temperature variance coefficient  were also summed up by experiments. It has important significance to understand the heat-conducting property and simulate temperature field of geotechnical materials in northern China.
Effect of Soil Moisture on Soil Temperature Field Near Buried Pipe
Authors: Li Jiang , Fu Jun Ping , Xie Wu Gang
Published: October 2012

System effectiveness and useful life of heat pump are directly affected by whether the design of ground heat exchanger is reasonable or not. The efficiency of heat exchanger has a close relationship with soil thermal conductivity coefficient and heat diffusivity, while soil moisture content affects soil thermal conductivity coefficient and soil temperature field. In this paper, we perform numerical simulation on CFD software. Then we study the soil temperature changes through field experiment in different soil moisture content on field experiment and finally obtained the relationships of the moisture content with the single U ground soil temperature field.
Analysis of Settlement of Composite Foundation with Sparse Pile to Control Settlement
Authors: Zhang Jun Hui , Yin Zhi Yong , Zheng Jian Long
Published: October 2012

The embankment soil arching effect of the composite foundation with sparse piles to control settlement is caused by the differential settlement between the embankment fill and the piles. So, the settlement is an important behaviour of the composite foundation. The effects of the height of embankment, the elastic modulus of geosynthetic and pile material, the stiffness of cushion and substratum, the pile cap and the distance of piles on the settlement are investigated using the computer code ABAQUS in this paper. The results indicate that the maximum settlement and differential settlement decrease with the elastic modulus of geosynthetic, the stiffness of cushion and substratum. The maximum settlement decreases and the differential settlement increases with the elastic modulus of pile material. At the same time, the differential settlement of the embankment surface decreases with the height of fill and there will be an equal settlement plane when the fill reaches certain height. In addition, the distance of piles has a more significant influence on settlement than the dimension of pile cap.
CT Investigation of Fracture Mechanism of Soil-Rock Mixtures
Authors: Sun Hua Fei , Yang Zeng Kun , Xing Ming Xu , Ju Yang , Yang Yong Ming
Published: October 2012

Soil-Rock Mixture (SRM) is a unique type of geological material characterized by inhomogeneous composition and complicated structures. This paper investigated the fracture mechanisms that govern the strength and deformation of SRM subjected to uniaxial compression loads by means of computed tomography (CT) techniques. The self-designed loading devices and self-developed image processing program were applied to identify and quantify the fractures inside SRM during compressions. The results show that the internal fracture behavior of SRM greatly depends on the rock ratios of SRM.
Analysis of the Effects on Optimization Design about Double-Row Piles Retaining Structure
Authors: Wang Yu , Yang Yan Ting , Yu Feng , Hu Guang Lei
Published: October 2012

Double-row piles retaining structure has been widely used in the project now, but the stress mechanism of double-row pile is more complex; Its internal force and deformation are affected by many factors. Understanding and mastering its effects has an important significance for the design and the optimization of double-row pile supporting structure. According to the comparison of the measured data and theoretical calculation about original support scheme and optimized support plan and combined with the soil test data, this paper takes the Jinan Cultural Arts Center(Theatre) stage bin foundation pit as an example to analyse the main effects of optimization design about double-pile supporting structure. The results show that soil shear strength, soil arch effect, influence of CFG composite foundation, pile-beam synergy effect and space effect of foundation pit play an important role for optimization design about double-pile supporting structure.
Characteristics of Cast-InSitu Concrete Pipe Pile under Lateral Load
Authors: Ma Zhi Tao , Wang Yong Ping
Published: October 2012

The cast-in-situ concrete pipe pile is a new kind of pile used widely in China to improve the soft ground. In this paper, the general introduction of this pile was given, mainly including the pile driving machine, the technique of pile working and the structure of pile. At last, one in situ test of this pile under lateral load were given, the characteristics of displacement of pile body and displacement of pile top were analyzed. These results can give a reference for practice project.
A Sufficient Condition for Irregular Shearlet Frame
Authors: Zhu Xiu Ge , Wu Guo Chang
Published: October 2012

Frame theory plays an important role in signal processing and image processing. The shearlets provide optimally space representations for 2D functions that are smooth away from discontinuities along C^2 curves. In the note, a new sufficient condition for irregular shearlet frames is presented. This provides a theoretical foundation for the applications of shearlets in the engineering.
Unifying Section of Chord Member of Transmission Tower Based on Recursion Method
Authors: Wu Di , Xiong Yan , Cui Lei
Published: October 2012

A unifying section problem of a double circuit power transmissions tower (DCPT)’s chord member was studied in this paper. The collision between the theoretic analysis and practical process in optimization of unifying section was proposed. The bourn of each chord member’s broken position was taken into consideration. The concept of dynamic programming was cited, and a procedure to get all the feasible combination patterns for unifying section was put forward by recursion. The object function which is the combination of the decision making and the state in every phase was set up. The object function value of whole structure can be obtained based on the previous decision of every phase. The optimization value in a decision of the weight of the tower’s chord member was set up though above object function value in a certain combination. At last, the optimization solution is designed via selecting a series of self calling functions on the basis of recursive idea.
Experiment and Theory Study on Ultimate Bearing Capacity of Reinforced Concrete Tubular Hollow Continuous Slab
Authors: Zhang Zhen Hao , Yang Wei Jun , He Zhi Gang
Published: October 2012

The tubular hollow slab inside which GBF high-strength thin-wall pipes are placed is a new type of hollow structure. First the ultimate bearing capacity of tubular hollow continuous slab is measured by experiment. Then the ultimate bearing capacity of the tubular hollow continuous slab is studied by plastic limit analysis method. And the complete solution of structural ultimate load under condition of full internal force redistribution is solved. The study show that the measured values of ultimate load are all a little larger than the theoretical values of ultimate load, which shows that the tubular hollow slab develop full internal force redistribution. So it can be concluded that the tubular hollow slab has fine performance of plastic internal force redistribution.
Characteristics of Wind Loads on Long-Span Roof
Authors: Chen Fu Bin , Li Q.S. , Fu Ji Yang , Wu Jiu Rong
Published: October 2012

In recent years, many large span roofs of airport waiting room and garage were destructed in the tropic storm, which have the characteristics of light mass, high flexibility, slight damping and low natural frequency. Wind loads general control the design of such structures. Thus, the tests of wind pressure with the rigid scale model in boundary layer wind tunnel were conducted in the structural design stage. This paper presents the results of characteristics of wind loads on large-span roof structure of the Guangzhou International Convention & Exhibition Center (GICEC) in frequency domain. The power spectrum densities, correlation coefficients, coherence functions and probability density function (PDF) were analyzed in detail. The results can be summarized as follows: (1)The power spectrum densities of fluctuating wind loads have the characteristics of vortex shedding and the Strouhal number is about 0.295; (2)The coherence coefficients decrease with the frequency and the spatial distance increase at both the along-wind and across-wind direction; (3)There are clearly negative skewed distributions for some pressure taps at the windward leading roof edge and much longer negative tails are observed, which follow Non-Gaussian distributions. The results presented in this paper are expected to be of considerable interest and of use to researchers and professionals involved in designing complex long-span roof structures.
A Settlement Compensation Method for Design of Settlement Controlled Piled Raft Foundations under Vertical Loadings
Authors: Wang Cheng Hua , Cao Jun Nan , Zhao Liang Liang
Published: October 2012

In order to analyze the behavior of piled raft foundations under vertical loadings, a simplified method called settlement compensation method (SCM) is proposed based on the basic principles in the code for design of building foundation of China. The effect of several influence factors of the SCM was investigated through an exemplar case. The applicability and accuracy of SCM was checked theoretically with a finite element analysis, and verified practically through a case study in which the results of settlement analysis of other methods were included for comparison.
Analyses of the Elastic Modulus Values of Masonry
Authors: Ni Yu Shuang , Yang Wei Jun , Jiang Yao Hua
Published: October 2012

Abstract: The elastic modulus values of masonry were studied by using homogenization with microscopic mechanics. The formulate of the elastic modulus of brick masonry were derived from the formulae of the elastic modulus and Poisson’s ratio of brick and mortar. The calculated results according to the methods agreed better with our current national codes and the frequently-used formulas. This has paved the way for the study of the failure mechanism of masonry ,and make the analysis of masonry structure more accurate more and convenient.
Design of Steel-Bamboo Composite Structure System
Authors: Du Yong Fei , Li Yu Shun , Yang Bo , Huang Jun Guo
Published: October 2012

In order to make good use of bamboo resources in China and to promote the establishment and promotion of green structure system, which is light and energy saving, this paper presents two kinds of structure form: the composite walls bearing box structure system and the composite beam-column bearing frame structure system. Meanwhile, the design methods of connection and installation of steel-bamboo composite structure system are introduced.
Effect of Urbanization on Precipitation in Yangtze River Delta
Authors: Yang Ming Nan , Xu You Peng , Ding Jin Jia
Published: October 2012

Taking Yangtze River delta(YRD) as the typical region, on basis of daily rainfall data from 1961 to 2006, this paper made contrastive analysis of annual and flood season precipitation between cities and suburbs in the study area with the method of statistical analysis，linear regression and R/S method. The results showed that 1) on the scale of region, for the area with relatively rapid development of urbanization, increasing trend of rainfall in urban areas was more than that of suburban areas, while for the areas with relatively slow development of urbanization, the gap was not obvious; 2) on the scale of city, for the city with relatively rapid development of urbanization, the increase amplitude of rainfall and urban-suburban gap were both obvious, for which with relatively slow development of urbanization, both were not obvious. This study can provide a reference for the analysis of urbanization.
A Brief Analysis of Planning Approaches to the Reduction of Urban Carbon Emissions
Authors: Huo Yong Jun , Pu Li , Zhao Wu
Published: October 2012

Urban area is the main area from where our planet’s carbon discharges. It is generally accepted that the reduction of carbon will result in lower rate of economic growth. On the condition of not containing economic development, from the perspective of urban Planning, this paper tries to explore the planning approaches to the reduction of urban carbon emissions in terms of plans for the development of industries, city scale, urban spatial context, urban transportation, urban green space, architectural patterns, energy planning and urban water supply.
Study on Grassland Environment Capacity of Damao County Inner Mongolia
Authors: Shan Dan , He Jing Li , Liu Yan Ping , Liu Tie Jun
Published: October 2012

The environment capacity is not only importance to maintain the balance of nature, but also influence the socio-economic development well being in grassland regions. Take the case of Damao County in Baotou City Inner Mongolia located on the arid and semi-arid area in northern China and a fragile ecosystem, indicators system of grassland environment capacity are constructed and then analyzed the grassland environment capacity quantitatively. The result shows that the grassland environment capacity is an allowable state in 1992 and 2000, but it is an overloading state in 2009, so natural resources on the grassland has not support the demand of regional economic and social development based mainly on animal husbandry in Damao County, applying some effective measures to protect grassland and maintain ecosystem stability.
The Study of Carbon Dioxide Flux on Xilamuren Grassland Based on the Eddy Covariance Technique
Authors: Liang Zhan Qi , Shan Dan , Rong Hao , Xing En De
Published: October 2012

The eddy covariance is a micrometeorological technique to observe and investigate ecosystem flux nondestructively, as well as the main method the eddy covariance may help to research carbon dioxide exchange between global vegetations and the atmosphere. Carbon dioxide flux has been monitored on Xilamuren grassland of Wulanchabu city by Open Path Eddy Covariance System (OP-2). Carbon dioxide flux shows that carbon absorption is greater than its release, which has an evident carbon sink functions and obvious seasonal variety on the basis of experimental data from June 2009 to July 2011.
Study on the Interaction Characteristic of Wind-Water Alternate Erosion of Mid-West Desert Grasslands in the Inner Mongolia
Authors: Liu Yan Ping , Shan Dan , Liang Zhan Qi
Published: October 2012

In recent years, as a result of personal factors and natural factors of climate, soil, vegetation and so on, grasslands eco-environment worsens continuously, desertification is intensifying and soil and water loss is very severe, which is directly threatening to the national ecological security and sustainable development of national economy. On the basis of predecessors' achievements and our previous work, selecting the WuLanChaBu desert grasslands of the inner Mongolia as main study areas, where soil and water loss is severe and wind erosion and water erosion interact, we using the research approach combining field survey，remote sensing interpreter with field dynamic observations to analyze and study the characteristic of wind-water alternate erosion of the desert grasslands.
Application of Gray Fuzzy Theory in the Post Evaluation of the Huaihe River Treatment Engineering
Authors: Gao Jian Long , Liu Jian
Published: October 2012

Chinese Huaihe River treatment engineering had made brilliant achievements which provided a reliable guarantee of social stability, development and prosperity of watershed economy. As a means of decision-making and management of construction project, the post evaluation of the project was an essential element of basic procedures of project management. Combined with the gray fuzzy evaluation method, project post evaluation on the Huaihe River engineering was conducted in this paper. The result showed that the gray fuzzy evaluation method could reduce the influence of subjective factors impacted on project post evaluation to some extent, and make the qualitative issues quantification possible.
Research Progress and Application Prospect of High Oil-Absorbing Resins
Authors: Liu Xin , Wang Yuan Sheng , Yu Hong Wei , Wei Zheng , Liu Nian
Published: October 2012

The high oil-absorbing resin is a new type functional polymer material. The recent development of high oil-absorbent resin and its properties and synthesis were introduced in this reviewpaper. The absorption principle and process of highoil-absorbent resin are also presented. The effect of monomer, crosslinking agent and pore forming agent on high oil-absorption properties of oil-absorbing resin is investigated. At last, the present applications of the high oil-absorbing resin in environmental protection and other industrial purpose are also mentioned.
Research of the Ecology Revetment Materials and Technology in Seawater Intrusion Area
Authors: Li Xiang Ran , Han Gang , Zhang Hua Fang
Published: October 2012

Traditional rock-soil revetment merely has the function of preventing soil erosion, but cannot restore the vegetation. As it is gradually ignored by people, ecology revetment technology is being utilized in construction step by step. But as to the genuine researches which refer to the application of combining ecological revetment material and technology, especially when it comes to choosing proper seaside and coastal ecological revetment material and common-used ecological revetment structure for seawater intrusion area, researches are comparatively rare. For this passage, the author are attempting to analyze and study the ecology revetment structure model through the mechanism of both dynamics and hydrology effect of ecology revetment, on the principle of succession and diversity of seaside and coastal ecological revetment vegetation type, for choosing proper seaside and coastal ecological revetment vegetation for seawater intrusion area, namely, Grid ecological revetment structure, Geocell reinforced crushed stone ecological revetment structure, 3D geotechnical net-mat revetment structure, Ecological concrete revetment structure, Ecological bag-retaining wall revetment structure.
Study on Influencing Factors of Asphalt Fume Releasing and its Hazards
Authors: Wang Xin Wen , Zhang Wei Jun
Published: October 2012

A large number of experiments were done in order to find out the main factors which have an influence on the asphalt flue production in asphalt road construction and to master its dangers. The results show that the asphalt flue production varies with heating temperature, heating time, the asphalt thickness and stirring rate significantly. accordingly these are the main factors which influence the asphalt flue production. Further analysis by means of UV spectrophotometer and liquid chromatography shows that the asphalt flue contains serious harm to human body, such as aromatic compounds, alkanes, and sulfur heterocyclic compounds and other substances. therefore some steps should be taken to inhibit the production of asphalt flue for reducing the hazards to construction workers.
Institutional Design of Behavior Right in Highway Project Management
Authors: Jiang Wu Jun , Wang Meng Jun , Zhong Yong Jun , He Jing Yu
Published: October 2012

For guaranteeing the collaboration between behavior subjects and the highest efficiency in cooperative tactics, collaborative approaches or authority approaches can be adopted to design the institution of behavior right configuration. The strategic point collaboration among highway project subjects lies in the considering of individual interest of behavior subject from overall collaboration surplus. The behavior right institution can regulate the distribution of overall collaboration surplus to realize the collaboration and the optimal overall profit in the highway construction project.
Optimization Research of Construction Inventory Management on Site Based on Inventory Theory
Authors: Zou Ai Juan
Published: October 2012

Inventory management is to improve economic benefit of project procurement management by means of dominating order cycle and order quantity to minimize the stocks and total cost under the circumstance of normal construction.Firstly,inventory management involves material order,and contractors need to calculate parameters such as order cycle,order fee,order quantity,stocks fee,order lead time and safe stocks in order to make the total inventory fee minimized during construction.This article applies one branch of operations research--"inventory" to optimize the inventory management.
Research on Fort of Chinese Ancient Military Defense System
Authors: Wang Xuan , Hou Xin
Published: October 2012

Fort defense was always being with external or internal strife in ancient China. According to the different characters and functions, the forts in military defense system are classified as five types: the administrative and military central fort, common garrison fort, fort of strategic pass, fort for transmitting information, and farming fort for military supplies. And the fort network system structure for military defense and the basic construction characters of fort are summarized. It is clarified that all kinds of defensive nodes set by forts formed ordered depth through the interconnection in different levels, and played an important role in the history of national military defense system.
Three-Dimensional Complex Construction Project Management Maturity Model: Case Study of 2010 Shanghai Expo
Authors: Hu Wen Fa , Li Da Wei , Hu Rong
Published: October 2012

The increasing complexity of construction projects as a common trend has had a significant impact on management maturity assessment and improvement for the project participating units, especially for the owners’ Project Management Office (PMO). While most maturity models are rationalistic, this paper presents a practical complex construction project management maturity model based on project management three-dimensional perspective. Integrating Organizational Project Management Maturity Model (OPM3) and Best Practices (BPs) derived from 2010 Shanghai Expo practice, this case-based maturity model is constituted by three sub-models: PBS Maturity, Process Maturity and Organization System Maturity. The model uses structured questionnaire consisting of BPs to implement assessment. The proportion of BPs achieved is considered as the maturity level of assessment objectives. Shanghai Expo AB Area is used to test the validity of the model. The result shows that owners’ PMO can assess and improve their project management maturity with the model effectively.
Mechanism Study of Conflict Analysis and Countermeasure about BOT Project Organization
Authors: Zhao Li Ku
Published: October 2012

This paper analyzes BOT project for its basic operational procedures and organizational structure. Conflict of BOT project organization is divided into two levels. On this basis, respectively, to the general contractor and the project company as its core, described main task undertaken by the project stakeholders. It establishes a knowledge-based difference, the two-level model for organizational conflict of BOT projects.
Architectural Experiment of the Chinese Traditional Painting
Authors: Dong Tie Xin , Yan Zhen Yu
Published: October 2012

It introduces the basic information of the Chinese traditional painting, Chinese traditional architecture, and analyses three approaches of the Chinese traditional painting. Indeed, it illustrates the architectural experiment of Wang Shu, according to the Chinese traditional painting.
The Study of Land Supply Management under Asymmetric Information
Authors: Li Xin Xin , Zhang Dong Li , Zhang Su Juan
Published: October 2012

At present, Real estate industry has become an important pillar of national economic development. The development of real estate gives great impetus to economic development. Land in China, as an important carrier and integrant part of real estate commodity, the way of its transfer has great influence on the price of real estate commodity. This paper deals with common problems and the harm in the process of land transfer, analyzes systematically the parties involved in land market with game theory, and proposes corresponding risk prevention measures.
Practice and Reform of Computer-Aided Architectural Design Teaching Course with Tarch Architectural Software
Authors: Zhao Wei Feng , Bu Guo Bin , Zhou Jing
Published: October 2012

On the basis of the careful analysis and summary of many years' teaching experience, this paper investigates the current status of computer-aided architectural design teaching course with Tarch Architectural software and puts forward a series of reform measures such as teaching method, teaching contents, education examination, etc. It’s a significative work for improving teaching level of computer-aided architectural design teaching course and preferably cultivating students’ practical abilities.