bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Influence of Fly Ash on the the Microstructural Characteristics of Sea Sand Concrete
Authors: Zhang Guo Liang , Chen Jian Bin , Mo Li Wei , Liu Jun Zhe , He Zhi Min
Published: October 2012

By using the electron microscope scanner, we have done some research and analysis about the internal microcosmic structure of sea sand concrete. And combined with micro-XRD analysis as well integrative thermal analysis, we made observations of the internal composition of sea sand concrete., studying the effect on which sea sand makes during concrete hydration and the effect which fly ash made on the micro-structural characteristics of sea sand concrete.
An Investigation of Strength and Deformation Behavior on Shale Ceramsite Concrete Shear Walls
Authors: Chen Wei Chao , Yang Wei Jun , Wang Tong
Published: October 2012

With cyclic quasi-static tests, the strength and deformation behaviors of five shale ceramsite concrete shear walls specimens were studied, the effect of height-width ratios and reinforcement ratios of shear walls were considered. The failure feature, strength, deformation behaviors of shale ceramsite concrete shear walls were analyzed after the test. Analytical result indicates that, the shale ceramsite concrete shear walls have good strength and deformation behavior and it can meet the requirements of the structure seismic. The calculation formula of resistance moment and the relationship between curvature ductility ratio and displacement ductility ratio were established for shale ceramsite concrete shear walls and the calculate results were compared with test results.
Fatigue Life Analysis of Asphalt Mixture Coupling with Loading Intermittent Time
Authors: Luan Li Qiang , Tian Xiao Ge
Published: October 2012

Repeated loading will produce cumulative damage to asphalt concrete, because of the visco-elastic property of asphalt concrete, a certain degree of self-healing may occurred in case the loads being taken away.( the healing effect is more obvious under higher temperature or pressure),this process can be indicated through adding the intermittent time factor to fatigue test of asphalt concrete .This study adds intermittent time factor to asphalt concrete fatigue testing through universal testing machine,, deeply analyzing the effect of intermittent time, confirming that 0.5 second intermittent time is a key time point to fatigue process ,fatigue rate under 15 °C is slower than that under 20 °C,and introducing the effect factor to the fatigue equation.
New Applications of Glass Materials in Buildings
Authors: Zhang Chao , Wan Jie , Wang Zhen Hua
Published: October 2012

With the development of economy, architectural form constantly update and development. High-rise buildings, long-span buildings, and Giant buildings are constantly emerging. Building function becomes more and more complicated and diverse. Furthermore, people's aesthetic requirement continues to improve, which makes the glass more and more widely used in public building. Because it is lightweight and transparent, glass has received more and more architect's favor in the modern architecture design.
TSDC Study of Space Charge Influence on PP Film by Steep Front Impulse Injection
Authors: Kong Zhong Hua , Xu Bei , Luo Zai Fei
Published: October 2012

Influence of DC and steep front impulse injection on space charge of PP by thermally stimulated discharge current (TSDC) are studied. The experimental results show that space charge of PP is almost irrelative to the rise time of pulse, but space charge has relationship with polarized field intensity and polarized time, which is similar to the theory of TSDC
Effect of Bamboo Powder on Curing Behaviors of Liquefied Bamboo-Based Resol Resin
Authors: Liu Xiao Huan , Zhang Ming Ming , Fu Shen Yuan , Li Shou Hai , Wang Chun Peng
Published: October 2012

Differential Thermal Analysis(DTA) and Differential scanning calorimetry (DSC) were used to study the effect of Bamboo Powder(BP) on the curing behavior of two types of liquefied bamboo-based resol resin(PBF). DTA analysis shows that the addition of bamboo powder to the PBF resin leads to low temperature and broad peaks in the DTA curves. It also accelerates the addition reaction in the curing process of PBF resin and reduced the peak temperature, activation energies for PBF resin . Bamboo Powder reduced the activation energies for resins because the bamboo powder maybe had selfcatalysis effect. The lowest activation energy for a PBF resin probably appeared about at pH 11.0 under alkaline conditions.
Experimental Study on the Crack Consequences of Shale Ceramsite Concrete Aggregate
Authors: Yang Wei Jun , Kong Qiu , Yu Zhou Ping , Ren Yi Chun
Published: October 2012

To analyze the influence of aggregate on shale ceramsite concrete cracks and to compare the crack resistance between shale ceramsite reinforced concrete and ordinary reinforced concrete under the static load, one normal reinforcement beam and seven reinforced ceramsite concrete beams were used to take static experiment by way of two symmetric loading method to get different damages and characteristics of crack beams under load at all levels of distribution.
Study on Structure and Performance of PTFE/YSZ Composite Microporous Membrane
Authors: Du Jin Li , Deng Xin Hua , Sun Yuan
Published: October 2012

In this paper, the crystallinity, tensile strength and hydrophility of polytetrafluoroethylene (PTFE) filled with 7wt.% Y2O3-ZrO2(YSZ) were studied using X-ray diffraction (XRD), mechanical property testing and low-temperature plasma. The results show that the crystallinity gradually increases while tensile strength decreases with the stretch ratio going up; with YSZ content increasing, the tensile strength increases while the crystallinity decreases.
Research of Mechanical Properties of Asphalt Pavement Materials with WMA and RAP
Authors: Yu Bao Yang , Wang Yu , Zhang Min Jiang
Published: October 2012

The objectives of this paper are to characterize the mechanical properties of porous asphalt pavement mixtures containing RAP and a WMA additive using Super pave gyratory compactor and dynamic modulus testing. Four types of asphalt mixtures were evaluated in this study. This study evaluated compaction energy index, permeability, indirect tensile strength, and dynamic modulus for all types of porous asphalt mixtures. All of the asphalt mixtures meet the typical minimum coefficient of permeability in this study. In addition, only a slight decrease in was found when WMA additive was added to the porous asphalt mixture containing RAP. For indirect tensile strength testing, WMA containing RAP was found to have the highest tensile strength among all of the mixtures tested.
Preparation of Polyurethane-Poly(butyl acrylate) Hybrid Latexes via Miniemulsion Polymerization
Authors: Wang Shi Jie , Wang Yu Li , Yang Peng Fei , Li Tian Duo
Published: October 2012

Polyurethane prepolymer capped by vinyl group (PUV) was synthesized by reaction of hydroxyethyl methacrylate and toluene diisocyanate using di-n-butyltin dilaurate as catalyst, and then polyurethane-poly(butyl acrylate) hybrid latexes were prepared via miniemulsion polymerization of PUV and butyl acrylate (BA). Fourier transform infrared, differential scanning calorimeter were adapted to characterize the structure of PUV and PU-PBA and the properties of their films. The results show that the decrease of BA/PUV ratio result in an increase of the hardness and glass transition (Tg) of PU-PBA, but reduce the stability of miniemulsion and elasticity of final copolymer films.
Experimental Research on the Change Rule of Frequency of Shale Ceramsite Reinforced Concrete Beam with Damage
Authors: Yang Wei Jun , Kong Qiu , Yu Zhou Ping , Ren Yi Chun
Published: October 2012

Taking vibration test on 7 shale ceramsite concrete beams and a reinforced concrete beam, collecting the dynamic signals, and modal analyzing it, this paper studies the ceramsite diameter /strength and the injury at all stages impact on the frequency so as to guide the design and construction of shale ceramsite reinforced concrete structures and components.
Effects of Fiber Content and Water Ratio on the Strength of Fiber Reinforced Mortar
Authors: Wang Yao , Xuan Wei Hong , Chen Yu Zhi , Chen Xiao Hong , Zheng Gang
Published: October 2012

The compressive and flexural strength of ordinary mortar and fiber reinforced mortar with five different pp fiber content were tested in this paper. The results show that the compressive strength reduced gradually with PP fiber increasing, and the flexural strength increased when the fiber volume fraction is no more than 0.12%. The higher water ratio can weaken the cohesiveness of the fiber and cement material, and the influence of polypropylene fiber on the flexural strength of mortar decreased after soaking. The major strength damage in the process of curing is caused in the early age and appropriate amount of fiber is beneficial to reduce strength damage.
Effect of Heat-Curing Procedure on Strength and Microstructure of Reactive Powder Concrete Having High Volume of Mineral Admixtures
Authors: Peng Yan Zhou , Yang Wen , Zhu Qiao Sheng
Published: October 2012

The effect of heat-curing procedure on strength of reactive powder concrete (RPC) having high volume of mineral admixtures, such as ultra-fine fly ash (UFFA), steel slag powder (SS) and silica fume (SF) was studied in this paper. Moreover, the effect of the cuing temperature (20°C, 60°C and 90°C) and the duration (1 day and 3 days) of heat-curing both on microstructure of RPCs’ samples were investigated by SEM-EDXA. The results indicate that the heat-curing procedure has a great influence on strength of this RPC; the compressive strength of specimens cured in a appropriate condition could achieve more than 190 MPa. Moreover, a high curing temperature or a long duration of heat-curing will cause not only a high degree of pozzolanic reaction but also a low n(Ca)/n(Si) ratio of hydration product. Thus, the microstructure of the paste becomes more compact, which would definitely improve the mechanic properties of the hardened paste.
Experimental Study on Force-Bearing Performance of Road Concrete which Modified by Fiber and Rubber Powder
Authors: Li Hong Bo , Wang Bo , Zou Yuan Yuan
Published: October 2012

Test items include compressive strength, anti-breaking strength and split strength of standard concrete, rubber concrete and fiber-rubber concrete, and 43 groups test were conducted. In order to investigate the influence of the synergistic reaction between fiber and rubber powder on force-bearing performance of concrete used in subgrade, and different blended ratio effect on strength and extension of concrete were studied. The results indicated that with the increasing of content of 40 mesh rubber powder, the compressive strength of concrete decreasing regularly; with adding the blends of fiber and rubber powder, the anti-breaking strength and extension of concrete were promoted, as to fiber - 40 mesh rubber powder concrete, the content of rubber control less than 6%, and the fiber less than 0.5%，as to 60 mesh rubber powder -10mm fiber concrete, the content of rubber control less than 6%, and the fiber less than 0.5%; as to 60 mesh rubber powder -20mm fiber concrete, the appropriate adding quantity of rubber less than 2%, and the fiber less than 0.5%.
Load-Bearing Capacity of CFDST Based on the Unified Strength Theory
Authors: Xia Gui Yun , Li Jia Jun , Yang Mei Liang
Published: October 2012

Based on the unified strength theory presented by Maohong Yu, the calculating formula for the load-bearing capacity of concrete-filled double steel tube was derived. Through tests, the calculating load-bearing capacity results were compared with testing results, which agreed well. The change of load-bearing capacities with parameter k of the unified strength theory was discussed. It can be drawn that the load-bearing capacity of CFDST will increase with the increase of parameter b, but the increase is not obvious.
Dynamic Mechanical Behavior Study for the Fabricated Composite with High Anti-Corrosion Properties
Authors: Liu Guo Ning , Zhao Hua Dong , Li Yan Min , Zhu Qiang , Du Yun Hai , Zhao Ming Hao
Published: October 2012

Composite, with both sides deposited by pure aluminum (Al) thin films to improve its anti-corrosion properties, is designed and fabricated in this study through thermo-mechanical processing techniques. Manufactured composite here mainly consists of polyester textile and PET thin films. Mechanical tests are carried out to study the dynamic mechanical behaviors of the fabricated composites under various loading rates. Our works reveal that proper bonding material and appropriate processing are key and essential in order to fully make use of the excellent mechanical properties of polyester textile in the composite.
The New Synthesis of Novel Organic Light-Emitting Material Spirobifluorene by Ullman Coupling
Authors: Lou Ya Zhou , Sun Xiao Xia , Li Ying Chun
Published: October 2012

A mide, simple and efficient synthetic procedure for the preparation of 2,7-dibromo-2′,3′,6′,7′-tetra(2-methylbutyloxy)spirobifluorene and key intermediates, tetra(2-methlbutyloxy)biphenyl ，2-bromo-4,5,3′,4′-tetra(2-methylbutyloxy)biphenyl, 2,7-Dibromo-2′,6,3′,7′--tetra(2-methylbutyloxy)biphenyl-9-Fluorenol, has been developed. The procedure described herein offers several advantages, including high product yields, easy purification, and large scale production. Ether protected 2,7-dibromo-9,9′-spirobifluorene has good solubility in organic aolvents to permit an appropriate coating process, ability to achieve various colors so as to make full color display elements possible.
Effect of RE on Cyclic Oxidation Behavior of Ferrite Stainless Steel
Authors: Liu Xiao , Wang Long Mei
Published: October 2012

A primary study on the resistance to high-temperature-oxidation of 430 ferrite stainless steel and its oxidation process before and after the addition of RE elements was reported. Results show that the oxidation resistance of 430 ferrite stainless steel after adding RE is indeed great. The value of oxidation rate of Sample 1 (without adding RE) is 2.87 times higher than Sample 2, respectively at 1423K after oxidizeing for totally 144h. And the dense and adherent Cr2O3 scale and FeCr2O4 scale are formed and played the protection role to the 430 ferrite stainless steel. In the internal oxidation layer, the pinning effect of silicon dioxide is strengthened by RE.
Toughening Analysis for Eutectic Composite Ceramic Containing Lamellae
Authors: Ni Xin Hua , Chen Cheng , Liu Xie Quan , He Wan Heng
Published: October 2012

On basis of the residual-stress-field of the composite ceramic, the frictional force on the boundary of the lamellae can be computed. Then the frictional work is determined. The pull-out toughening mechanism is gotten. The result shows that the toughening value is dependent on the size of lamellae: the pull-out toughening value will increase as the thickness of the lamellae increase.
The Research on Hot Compression Mechanism of Light Alloy
Authors: Liu Jun Wei , Lu Shi Qiang , Dong Xian Juan , Xiao Xuan , Li Gui Fa
Published: October 2012

In this research, in order to explore the main mechanism of direct and two-stage compression in as-cast light alloy, the mechanical property, microstructure evolution and the flowing of second phase particles were studied, before and after deformation. Then, the influence of the strain volume in first stage on flowing stress of the second stage deformation also was researched.
Numerical Evaluation of the Active Earth Pressure Acting on Rigid Retaining Walls
Authors: Feng Shi Lun , Li Jun , Li Pu Lin
Published: October 2012

The active earth pressure on rigid retaining wall is analyzed using the finite element software ABAQUS. The fill behind the wall is sand and the Mohr–Coulomb constitutive model was used to model the stress–strain behaviour of soils.The finite element analysis results were compared with the Rankine results. The maximum error of the results is about 10% and the finite element analysis result is bigger. So the result obtained from the finite element method could safely be used in actual projects.
The Effect of Curing Time on Compressive Strength of Composite Cement Concrete
Authors: Uddin Md. Alhaz , Jameel Mohammed , Sobuz Habibur Rahman , Hasan Noor Md. Sadiqul , Islam Md. Shahinul , Amanat Khan Mahmud
Published: October 2012

The effect of curing condition of five different composition of Portland composite cement (PCC) and ordinary Portland cement (OPC) were investigated in this study. Compressive strength development of five different concrete types has been investigated in terms of cement content and curing duration. From the experimental observation, it is found that the early age strength of concrete made with PCC is lower than that of concrete made with OPC due to the presence of fly ash in PCC which is responsible for the pozzolanic reaction. The continued pozzolanic activity of fly ash contributes to increase strength gain at later ages at continued curing condition. It is also found that drying ambient conditions reduction of the strength potential of concrete made with PCC because the secondary (pozzolanic) reaction fails to contribute to the development of strength.
Deterioration of Enamel and Epoxy Coated Steel Rebar in 3.5 wt.% NaCl Solution
Authors: Tang Fu Jian , Cheng Xiao Ming , Chen Gen Da , Brow Richard K. , Volz Jeffery S. , Koenigstein Michael
Published: October 2012

Reinforcing steel bars coated with pure enamel and fusion-bonded epoxy (FBE) were immersed in 3.5 wt.% NaCl solution for a period of 84 days. Predetermined damage of the coatings was created with a standard impact tester to study the coating resistance to potential damage caused during transportation and construction. Open-circuit potential and electrochemical impedance spectroscopy (EIS) tests were used to investigate deterioration processes of the two coating systems. An equivalent electrical circuit model was established to extract corrosion-indicative dielectric properties of enamel and FBE coatings from the EIS data. The change of coating capacitance over time was represented by a diffusion-controlled process. In comparison with the FBE coating with the same extent of damage, the enamel coating corroded sooner due to its thinner layer and porous microstructure, but deteriorated more slowly due to its robust bond with the steel substrate.
Preparation and Characterization of Microencapsulated Phase Change Coating
Authors: Yu Jian Xiang , Liu Tai Qi
Published: October 2012

Microencapsulated phase change materials were achieved by solvent evaporation in this article, using polymethylmethacrylate as capsule’s shell and inorganic salt CaCl2•6H2O as capsule’s core. the effects of emulsion concentration and different ratio of core and shell to the microencapsulated phase change materials were discussed. The phase change material were added to the interior wall paints and its properties were characterized. The results showed that its enthalpy content will be different with the microcapsules and different storage time.
Synthesis and Characterization of Poly(N-Arylenebenzimidazole Ketone)
Authors: Xu Ye Wei , Tang Jie , Chang Guan Jun , Zhu Fang Hua , Zhang Lin
Published: October 2012

Using 1,4-bis(2-benzimidazolyl) benzene (BBIB) and 4,4'-difluorobenzophenone as the monomers, poly(N-arylenebenzimidazole ketone) (PNABIK) has been prepared via the aromatic nucleophilic displacement reaction. The chemical structure of PNABIK was confirmed by FT-IR, elemental analysis and 1H NMR. The results show a good agreement with the proposed structures. The polymer was obtained in quantitative yields with Mn value 12500 and Mw value 28600, respectively. DSC and TGA measurements show that the glass transition temperature (Tg) is 202 °C and 5% weight loss temperature is 550°C in nitrogen and 571 °C in air, respectively. In addition, the novel polymer exhibit good solubility.
Dynamic Penetration Tests (DPT) at Gravelly Soils Liquefaction Sites
Authors: Cao Zhen Zhong , Xu Xue Yan , Yuan Xiao Ming
Published: October 2012

The Chinese Dynamic Penetration Test (DPT) was used following the 2008 Wenchuan earthquake to measure penetration resistances of gravels that liquefied and nearby gravels that did not. The test has many advantages, including simplicity, continuous data acquisition, and robust equipment that is easily transported by light vehicles and low cost. A probability formula, developed from logistic procedures, was proposed using the 47 compiled DPT data. The DPT could be a viable test for measurement of penetration resistance of gravels in other parts of the world beyond China.
Influence of Covering Layer on Surface Temperature of Floor Radiant Heating System
Authors: Zhao Hai Qian , Wang Zhong Hua , Zhang Lan Shuang
Published: October 2012

Floor radiant heating system has many advantages, energy and space saving, for example. The radiant floor is the radiator of floor radiant heating system, and its thermal parameters influence surface temperature distribution and comfort. In this paper, mathematical model of heat exchange coil under floor was established, and boundary heat transfer conditions were given. Based on these, surface temperature of different covering layer was calculated. According to the results, using different covering layer, the floor surface temperature has a great difference. Using wooden floor as cover material, the floor surface temperature is more moderate and uniform.
Stress Influence Factor Analysis of Gas Pipeline in the Tunnel
Authors: Wu Xiao Nan , Ma Hong Yan , Zhou Ying , Hu Mei Lin , Xian Yan
Published: October 2012

The laying of gas pipeline with tunnel crossing method, except under the influence of pressure, temperature, and out of gas direction, it also subjected to constraints of soil, soil temperature, terrain conditions and the impact of earthquakes. Also crossing pipes are in the constraints of fixed pier, anchorage pier and pier pipeline deformation, which makes the stress analysis of boundary is difficult to determine. In order to compare the effect of different constraints and out of gas direction on the entire tunnel crossing pipeline under operating conditions, this paper has established three pipe models: the symmetrical form of the direction of access to gas, completely without supporting (do not canceled the fixed pier at both ends)and with supporting form, then the primary stress, secondary stress and compound stress are checked in turn. By comparing their impact on the stress of the whole pipeline, we get the importance and extent of the main constrains on the pipeline stress.
Study on the Ventilation and Dehumidification System Integration Framework for City Buildings in Hot Summer and Cold Winter Zone
Authors: Yu Xiao Ping , Fu Xiang Zhao
Published: October 2012

Building ventilation has typical regional characteristics, due to its annual high wet climate characteristics in hot summer and cold winter area, the choice of ventilation type is especially important. The present building energy consumption simulation and thermal comfort evaluation of is inadequate to air humidity effects, and easily to ignore ventilation energy saving potential with building thermal environment control. In this paper based on the region annual building humidity environment characteristic, author put forward a kind of building ventilation and dehumidification integrated solutions, from a methodological point of view to explore a ventilation and dehumidification integrated technique with air conditioning and heating period , try to deal with the indoor thermal environment quality problems with lower energy consumption.
Discussion on the Design of Freezing Dehumidification-Based Radiant Air-Conditioning System
Authors: Tan Chao Yi , Wang Han Qing , Zhu Hui
Published: October 2012

For the purpose of realizing non-dewfall condition of the radiant panels, low energy consumption and nice comfort of the freezing dehumidification-based radiant air-conditioning system, the design temperature and humidity of the room were figured out according to the mean comfort index of human body during the design. And in order to lower the energy consumption, the necessity of the reasonable load allocation between the dehumidification unit and the radiant unit was discussed by means of the calculation with the quasi heat-humidity-ratio line. As a result, much more precise design parameters were acquired through the approximation calculation. And it was proven to be a good design method by applying these parameters to the design of the reading rooms of the library. In the design example of the reading room, the load ratio between the dehumidification unit and the radiant unit was 48 to 52, and the recirculation air flow rate of the dehumidification unit was not less than 36.8% of the total air rate of the room.
Research of Energy Saving Control for Central Air-Conditioning Based on Adaptive Fuzzy PID Method
Authors: Sun Jian Min , Zhang Chun Dong , Zhou Ze Yang
Published: October 2012

Central air-conditioning control system have characteristics of susceptible to outside interference, nonlinear, time-varying, hysteresis and difficult to build precise mathematical model. Central air conditioning chilled water system with variable water flow was taken as subject. According to the principle of energy saving, on the basis of traditional PID controller, adaptive fuzzy PID controller was designed. Fuzzy control algorithm determines the choice of parameters of PID controller KP、KI、KD , with which, then, regulate the output of adaptive fuzzy PID controller; Finally the output value determination of the operation frequency of the chilled water pumps. Compared with conventional system temperature control, adaptive fuzzy PID control in central air conditioning system has good energy-saving effect.
Study on Strength Reduction Method with Two Reduction-Factors
Authors: Yang Ping , Zhu Zhan Yuan , Zou Zu Yin
Published: October 2012

Because development degree and order as well as decay rate and degree of shear strength indexes, cohesion C and angle of internal friction , are not equal as slope failure, both should have their own security reserve. For this reason, it was proposed that C and  should have different reduction-factors, rather than same about strength reduction method (SRM). And to take a slope as an example, by FLAC SRM and strength reduction slice method (SRSM), reduction-factors of the two indexes and dangerous slide surfaces of the slope were computed and comparatively analyzed under 9 different reduction conditions. The results obtained by FLAC SRM and SRSM accorded with each other well. Therefore conclusions can be drawn that different reduction conditions correspond to different two reduction-factors and dangerous slide surfaces, so that all these dangerous slide surfaces form a dangerous slide region; single reduction-factor method that reduction-factors of C and  are same is only a special case of two reduction-factors method; two reduction-factors method can just reasonably reflect respective roles of C and  as slope instability. The conclusions in turn confirm the above-mentioned viewpoint again.
Evaluation of the Influence of One Air Circulation System on LGS House Indoor Thermal Environment
Authors: Li Jing , Deng Zhi Qiang , Li Chuan , Zhou Di
Published: October 2012

Basing on 3 dimensional simulation of Airpak software, it studied the indoor thermal environment characteristics and influence factor of LGS house which provided with one air circulation system. It investigated the indoor air flow velocity field, temperature field, air age distribution and PMV-PPD distribution, and completed prediction and evaluation for air flow organization and air quality. The study shows that this air circulation system improves the air flow velocity and temperature distribution of LGS house indoor, provided a good thermal environment and air exchanging effect for indoor with low energy consumption, this has a significant meaning for improving comfort level of LGS house on the basis of meeting green energy saving.
Experimental Verification and Analysis of Thermal Comfort with Radiant Floor Cooling
Authors: Li Qi Fen , Zhou Zhi Tian , Sun Wei Dong , Li Tao , Zhao Li Feng , Pan Cui Cui
Published: October 2012

Radiant floor cooling is a new energy saving air conditioning. In recent years, radiant floor cooling effect and its thermal comfort are still in the exploratory period in China. The body's comfort evaluation methods are briefly described in this paper. The indoor temperature and wall temperature of the building envelope determination method is analyzed. Nanhui Art Hall is used as object of study in this paper. Combined with the radiant floor cooling experiments, and using fanger formula calculation, the thermal comfort is calculated. Proper analysis of the results is in two aspects: the clothing thermal resistance and indoor air humidity. With the floor surface temperature below 21.56 °C, and air humidity 55% to 65%, it can meet the requirement of thermal comfort. The result will provide a helpful reference to energy-saving technologies and energy-saving equipment.
Heat Flux through Naturally Ventilated Building in Malaysian Climate
Authors: Morris Freda , Zakaria Nor Zaini , Zain Ahmed Azni
Published: October 2012

Roofs and walls are the main media for heat transfer for typical Malaysian buildings. In order to estimate the duration of uncomfortable periods, the environmental temperature of a building was determined over a period of time. A study of heat flux through a naturally ventilated was conducted by simulation. This study focused on heat transfer through the roof, ceiling and vertical walls. A Thermal Analysis Software was used for the modeling and analyses. A virtual test building model dimension 4m x 4m x 3m was created using conventional construction parameters for roof, ceiling, windows, door, walls and floor which meet the minimum requirement in Malaysian Standards. The results show that heat rate flux mostly peak at east wall before 12:00 hrs and west wall after 12:00 hrs. The heat rate flux through the roof is higher than that through the ceiling during daytime but lower at night as roof was the surface of most exposed to solar radiation. The proportion of heat through roof was 87% by radiation, 11% by convection and 2% by conduction. 97% of heat was transferred by radiation and 3% by conduction for ceiling and heat through wall was 88% by radiation, 8% by convection and 4% by conduction respectively.
Mode-II Stress Intensity Factor by Triangular Williams Element with Generalized Degrees of Freedom
Authors: Xu Hua , Yang Lu Feng
Published: October 2012

A new triangular Williams element with generalized degrees of freedom (GDOFs) was proposed for analysis of stress intensity factor (SIF) of mode II crack. The singular region around the crack tip was evenly divided into a series of triangular elements, which could be approximated by the improved Williams series. On the basis of the principle, the displacement of local field must be compatible with that of the global one, so that the SIF at the crack tip can be directly evaluated by one of the undetermined constants of the Williams series. Three important parameters for the triangular Williams element, including the radial scale factor, the number of subelements and the terms of the Williams series, were discussed in detail. Numerical example shows that the triangular Williams elements with GDOFs can directly calculate the mode II SIF with high accuracy and efficiency.
Numerical Simulation Analysis on Mass Concrete Thermal Stress
Authors: Tian Guo Liang , Wang Yin
Published: October 2012

Cement hydration heat temperature of the concrete could result thermal stress. Which is an important reason for the concrete structure’ cracks. The cracks could reduce the structure’ durability and structural stability. A spatial finite element model analysis on a mass concrete foundation board of a project was established using large-scale finite element analysis software. Temperature stress finite element analysis was carried on model. Numerical simulation analyzed the hydration heat of mass concrete construction phase and calculated the mass concrete’ temperature and stress distribution. Results of numerical simulation of crack control had certain guiding significance to mass concrete construction.
An Eigenfunction Expansion Method in the Stress Concentration Analysis
Authors: Bai Yang , Chen Li
Published: October 2012

This paper deals with the traditional stress concentration problems based on the eigenfunction expansion approach. Due to the completeness property of the eigenfunction space obtained by the previous researches, the solution of an arbitrary problem can be expressed by their linear combination. Thus the original problem is transformed into finding the combination of these eigenfuctions satisfying boundary conditions. By applying adjoint symplectic relationships of the ortho-normalization, the combination can be obtained numerically. Numerical results in tensional problems show that stress concentration appears when one of the ends of the solid is clamped. The concentration is seriously confined near the boundary of the fixed, and decrease rapidly with the distance of the boundarys.
Siltation of Approach Channel and its Influence on Ship Grounding
Authors: Li Ya Jun , Mou Jun Min , Ren Ya Lei , Lin Xue Jun
Published: October 2012

Ports at high siltation rates are covered with fluid mud layers which generally develop from short-term siltation. The presence of a fluid mud layer on the bottom of the channel has a considerable influence on ship behaviour, e.g. squat. The paper calculates siltation in an approach channel and its effect on ship motions. Firstly, siltation thickness and sediment density are predicted based on existing information of sediment, and the characteristics of mud layers are analyzed, Secondly, the squat and trim of ship navigating in the muddy areas are computerized. Finally a model through Monte Carlo simulation is presented to interpret the probability of ship grounding on the fluid mud layer.
Research on Mode of Deformation Forcasting Based on the Maximal Lyapunov Exponent
Authors: Wang Xiu Ping , Jiang Ting Chen
Published: October 2012

It is necessary for us to monitor and forecast deformation as harm of deformation is tremendous. At the same time, deformation is seen as power system with chaos features because process of deformation is easily influenced by geology、hydrology、earthquake and activity and so on. On the base of chaos theory, forecasting model based on the maximal Lyapunov exponent is put forward in this paper, and is checked by example of engineering. Research indicate that Chaos phenomenon exist in deformation sequence for Lyapunov exponents is bigger than 0. The forecasting results show that forecasting method based on maximal Lyapunov exponent has high predictive precision, so the method is proved to be feasible and referenced.
Rigidity Test Research of Rigid and Flexible Flange Connection in Power-Transformed Frames
Authors: Li Hong Bo , Yang Jun Fen , Peng Yi Liang , Xiang Yang
Published: October 2012

The existing research on flange focused on bearing capacity, and there were few reports on the rigidity of flange. In this paper, rigidity test was carried on for the connection of rigid flange and flexible flange in power-transformed frames. According to the test results, the axial rigidity, shear rigidity and flexural rigidity was compared. The results indicated that the axial rigidity, shear rigidity and flexural rigidity of flexible flange connection was lower than those of rigid flange connection for both the plain bolt and high strength bolt.
Nonlinear Dynamic Response of Buoys under the Collision Load with Ships
Authors: Chang Liu Hong , Jiang Chang Bo , Liao Man Jun , Xiao Xiong
Published: October 2012

The explicit dynamic finite element theory is applied on the collision of ships with buoys for computer simulation. Using ANSYS/LS-DYNA finite element analysis software, the numerical simulation of the collision between the ton ship and the buoy with different structures and impact points. The collision force, deformation, displacement parameters and the weak impact points of a buoy are obtained. Based on the numerical simulation results, analysis of buoys and structural collision damages in anti-collision features are discussed, and several theoretical sugestions in anti-collision for the design of buoy are provided.
Solving the Linear Time-Fractional Wave Equation by Generalized Differential Transform Method
Authors: Chen Xue Hui , Wei Liang , Sui Ji Zhe , Zheng Lian Cun
Published: October 2012

In this paper, the generalized differential transform method is implemented for solving time-fractional wave equations in fluid mechanics. This method is based on the two-dimensional differential transform method (DTM) and generalized Taylor’s formula. The results reveal the method is feasible and convenient for handling approximate solutions of time-fractional partial differential equations.
Identification Method Research of Elastic Buckling Load of the Compressed Beam at Two Ends Elastic Fixed
Authors: Du Ling , Li Fan Chun
Published: October 2012

From the basic equation of dynamics, the precise expression of the relationship, which is between the horizontal natural frequency and pressure load of the beam at two ends elastic fixed and subjecting to vertical pressures, is obtained. Its approximate expression derives from the variational method. By comparing the precise numerical solution and the approximate solution of the beam at two ends elastic fixed and subjecting to vertical pressures, the conclusion of approximate linear relationship that is between the square of the natural frequency and axial force of the beam at two ends elastic fixed and subjecting to vertical pressures is got. And the difference between the approximate solution and the accurate numerical solution is small, which can meet the requirements of accuracy on engineering. On this basis, as long as the natural frequencies of the structure at two load conditions are measured by experimental methods, elastic buckling load of the compressed beam can be identified. So the no damage test method to identify the elastic buckling load of the structures is given.
Non-Linear Finite Element Analysis of EPS Module Shear Wall
Authors: Zhang Min , Jin Ying Yu , Dou Li Jun
Published: October 2012

EPS module is connected like roy brick to form a hollow wall, then grouting the without vibrate concrete to form the thermal-insulating shear wall. Based on the experiment data, analyzed the aseismatic behavior of EPS module shear wall under horizontal cyclic loads by ANSYS software. Compared EPS module shear wall with the traditional shear wall on crack status, stress and strain distribution, rigidity, and attenuation coefficients of rigidity. Compared the experiment data with the finite element analysis result by ANSYS, discussed the method of analyzing this new plate material by finite element analysis, which can be basis for experiment and analysis on this material.
Existence of Nontrivial Positive Solutions to a Semilinear Elliptic System
Authors: Sun Da Wei , Zhu Gao Sheng
Published: October 2012

This paper studies the nontrivial positive solutions to a semilinear elliptic system in the n dimensional Euclide space. By constructing new variational space, using the linking theorems and some embedding theorems, this paper proves the existence of positive solution to a semilinear elliptic system, and improves the results of Li and Wang.
Energy Estimates of Strictly Contact Homeomorphisms in Contact Dynamical System
Authors: Sun Da Wei
Published: October 2012

This paper studies the reductions and properties of strictly contact diffeomorphisms in contact dynamical system. By constructing new norms and using some estimate techniques, this paper proves that the induced homeomorphism of contact homeomorphism is Hamiltonian, and computes the norm of such homeomorphism under reduction in contact dynamical system.
A Note on Exact Travelling Wave Solutions for Nonlinear PHI-Four Equation
Authors: Xiang Chun Huan
Published: October 2012

The purpose of this work is to reveal the dynamical behavior of the nonlinear PHI-four equation, which is an interesting and very useful model in particle physics and mathematical physics. As a result, travelling wave solutions of nonlinear PHI-four equation are formally derived by employing hyperbolic tangent method in this paper. This paper shows that hyperbolic tangent method can be a powerful tool in obtaining evolution solutions of nonlinear system.
Study on Concrete Dam Temperature Evaluation Based on Distributed Optical Fiber Temperature
Authors: Huang Yao Ying , Liu Dan Dan , Qu Li Xin , Zhou Yi Hong
Published: October 2012

The dam concrete material properties wre influenced by the implementation of temperature control measures on site. The weekly temperature evaluation system has been set up in order to evaluate current temperature control measures, combining with the distributed optical fiber temperature control techniques and construction technical requirements. The system has been applied to a concrete arch dam under construction in southwest China which established multi-objective fuzzy mathematical model by synthetic weighting method that was a combination of experts scoring method and entropy weight method. Practice shows that the system can estimate weak link of this week and give guidance to the temperature control’s adjustment of the following week.
A new Interface Element Method on Computation of the Interface Crack Propagation Energy Release Rate
Authors: Zhong Zhi Peng , Wan Shui , Zhou Lin Yun
Published: October 2012

A new interface element method was proposed to calculate the strain energy release rates(SERR) based on the virtual crack closure technique (VCCT). A Lagrange multiplier was introduced between the node pair at crack tip to obtain the internal forces. Then from the VCCT, the SERR was solved by using the forces and displacements near the crack tip. Examples for stationary cracks under the two typical cases are given. Meanwhile, the relationship curves between crack energy release rate and the length of crack, plate depths were plotted respectively.The example shows that the interface element used to calculate the SERR is simple, efficient, and highly accurate in analysis of 2D crack growth problems, and without requiring the special singularity element or collapsed element at crack tip.
Numerical Simulation of Ship Maneuvering on Bend Channel
Authors: Dong Bing Jiang , Lin Jiang , Chen Qian
Published: October 2012

Bend channel is common seen in inland waterways. Due to the complex flow conditions, it’s often of great difficulty for ship maneuvering. To improve navigation conditions, usually the regulation is needed. In this paper, a 3D flow simulation model and ship maneuvering model are coupled. Based on the simulation results, the navigation conditions in Yiyang-Lulintan waterway project are evaluated. The simulation based evaluation provides a scientific basis and guidance for regulation projects in bend channel.
Experimental Investigation on Tensile Mechanical Properties of CFRP-PCPs Composite Rebars
Authors: Liang Jiong Feng , Lei Huang , Deng Zhi Ping
Published: October 2012

The behavior of CFRP-PCPs composite rebars on tensile test was studied. Experimental results showed that using CFRP-PCP composite rebars as reinforcement utilizes high strength of FRP effectively, reducing the reinforcement ratio and consequently the cost while simultaneously satisfying structural requirements. Tension stiffening in CFRP-PCPs composite rebars is significant when higher concrete strength and higher prestressing level are applied.
Failure Analysis on Tube Socket Crack of Supercritical Boiler Water Wall Header
Authors: Zheng Xiang Feng , Jiang Yun Jian , Feng Yan Ting , Wang Qing , Niu Xiao Guang , Hao Xiao Jun , Li Wen Bin , Li Zhong Wei , Xu Xue Xia , Li Wen Peng
Published: October 2012

Through methods, such as microscope analysis, mechanical analysis, chemical analysis, metallography examination and scanning electron microscope etc, the causes resulting in lots of tube socket cracks of supercritical boiler water wall header (15CrMo) have been analyzed. The result indicates failure of the supercritical boiler water wall header tube sockets are the ductile fracture and belong to thermal stress crack. The unreasonable structure, excessive thermal stress between header and sockets are the primarily inducement of crack failure.
The Application of Pseudolinear Equivalent System in the Deformation Analysis of RC Structure Members
Authors: Yu Hai Xiang , Chen Xiao Yang , Wang Xue Yuan
Published: October 2012

A pseudolinear equivalent method is proposed to analyze the nonlinear deformation of reinforced concrete structure member. In this method, the real moment of a bending member is transformed into equivalent moment by means of acquiring the bending moment-curvature relation of the section, and then the equivalent concentrated forces along the member are gained through the differential relationship between bending moment, shear force and distributed force. By this method, the problem of nonlinear system can be transformed into the problem of linear system. This method can analyze the deformation of RC structure members with constant or variant sections, which can be extended to analyze the nonlinear deformation of the structure members made of other kinds of engineering materials. The analyzed result given by this method fits the result attained from finite element method very well, which proves the feasibility of the model.
Analysis of Four Finite Volume Schemes for Plane Stress Problems
Authors: Qin Yue Ping , Sun Quan , Yang Xiao Bin , Zhang Guo Yu
Published: October 2012

In order to compare precisions of different finite volume schemes for plane stress problems, this paper discussed three typical finite volume schemes(FVM2, FVM3 and FVM4) through theoretical deduction and example verification, and introduced a new scheme(FVM1). Force equilibrium equations were obtained, which derived from the principle of the finite volume method (FVM). Using triangular units and in view of internal cells and boundary elements, this paper put forward these four finite schemes linear equations similar to the finite element method(FEM) stiffness equations but with different coefficients. The analyses and numerical example results show that FVM1 is the optimal finite volume scheme, and suggest that in practical civil, architectural and hydraulic engineering calculations, schemes should be selected carefully and FVM1 is a good option.
Control Technology of Magneto-Rheological Damper Based on Impact Load
Authors: Li Fu , Lin Li Ping , Hu Wei , Meng Guang Lei
Published: October 2012

Magneto-rheological damper is an adjustable damping smart drive. Its advantage lies that the magneto-rheological fluid can rapidly and reversibly change Newtonian fluid with good liquidity into plastic solid with high viscosity and low liquidity in the millisecond time. And then it can be easily combined with control. MR damper has obtained a certain application in vibration control of automotive, machinery, construction and other areas. In this paper, the writer focus on describing control strategy present situation and the advantages and disadvantages of various control strategies of magneto-rheological damper based on impact load. And he makes a more detailed analysis of difficulties and future trends of magneto-rheological damper based on impact load.
A Novel RNA Genetic Algorithm for the Parameter Estimation of the Fluid Mechanics with Multiple Solutions
Authors: Fang Guo Hua , Si Xin Yi , Chen Xiao Ping , Zhou Jian Hui
Published: October 2012

In fluid mechanics, to obtain the multiple solutions in ordinary differential equations is always a concerned and difficult problem. In this paper, a novel RNA genetic algorithm (NRNA-GA) inspired by RNA molecular structure and operators is proposed to solve the parameter estimation problems of the multiple solutions in fluid mechanics. This algorithm has improved greatly in precision and the success rate. Multiple solutions can be found through changing accuracy and search coverage and multi-iterations of computer. At last, parameter estimation of the ordinary differential equations with multiple solutions is calculated. We found that the result has great accuracy and this method is practical.