bluuebunny/crossref_metadata_2025 huggingface dataset:
Indoor Thermal Comfort Predicting Correlations in Subtropical Plateau Monsoon Climate
Authors: Wei Sheng Xian , Zhou Qing , Tao Shu Fen , Chen Guang Xue
Published: August 2012

Fanger’s PMV is the most famous thermal sensation index but it is too complex to be applied in practice. Besides, the PMV index does not include the effect of hourly solar radiation on the indoor thermal climate. In order to obtain simple and applicable correlations with considerations of outdoor hourly solar radiation, a one-year measurement was performed in a naturally ventilated residential room in Qujing Normal University of Yunnan province, China. PMV indices are calculated by using Newton’s iterative method based on the collected data. Correlations of the PMV and the environmental parameters (outdoor air temperature, indoor air temperature, mean radiant temperature, wind velocity, relative humidity, hourly beam radiation and hourly diffuse radiation) have been developed by the multivariable regression technique. It is convenient to use them to predict the indoor thermal comfort in the subtropical plateau monsoon climate.
Study on Green Low Carbon Building Design Based on Photovoltaic Power Generation Technology
Authors: Fu Xiao , Shen Shi Guang , Yin Jie
Published: August 2012

Under the background of global warming, green low carbon buildings have become a trend which is considered to reduce the carbon emissions. This paper, on the basis of analysis on the traditional low carbon building design methods, puts forward a new concept of design supported by the technology of photovoltaic power generation. This paper introduces the development and principles of photovoltaic power generation and emphasizes the BIPV technology. Green low carbon building design based on BIPV can be divided into active and passive design, which all has a positive influence on the green low carbon design.
The Implementation and Case Study of the China Energy Efficiency Evaluation and Labeling System for Civil Buildings
Authors: Jiang Xiang Yang , Yang Jian Kun , Law Ching Hin
Published: August 2012

This research took Guangdong Science Center as a case study and demonstrated the methodology of the two-star qualification for China energy efficiency evaluation and labeling system. It presented the testing methods, evaluation principles and results of the basic, prerequisite and elective items which are explained from the contents and perspectives within the article as well as the implementation on this project.
Research on Pavement Performance of Flame Retarding Asphalt Mixture
Authors: Tian Bin , Zhao Liang , Wei Chuan Guang
Published: August 2012

In the pre-stage work, research of flame retarding asphalt with non-flammability level-2 has been completed and experiment and research of the asphalt pavement performance has been carried out. In this paper, through freeze thawing cleavage, track and low-temperature bending experiment of the mixture, overall research has been performed for high and low-temperature pavement performance of the flame retarding asphalt mixture by the phosphorous-phosphorous, halogen-phosphorous collaboration systems to analyze influences on pavement performance of flame-retarding asphalt mixture by flame retardants of different systems.
Regeneration Aggregate Concretes Enhancement Technology Experimental Study
Authors: Xu Yuan
Published: August 2012

The article analyzed the filling and repairing effect of ultra-fine fly ash about recycled concrete under different gradations. And obtained something by analyzing test data: ultra-fine fly ash could improve the recycled concrete workability and strength to some extent, but different gradations of the recycled concrete have different effects on strengthen. Recycled concrete strength increased by an average of about 15% after incorporation of ultra-fine fly ash. These conclusions could provide a certain reference value for the recycled concrete research and application of enhanced technology.
Effect of Steel Fiber on the Performance of Concrete Materials
Authors: Zhang Shi Ping , Dong Xiang
Published: August 2012

This paper presents the results of testing performed to evaluate the influence of steel fiber on the performance of concrete materials. The performance of concrete materials was studied through frost resistance, carbonation testing and restraint cracking testing. Experimental results show that the steel fibers can improve the frost resistance and carbonation of concrete, compared with plain concrete. Steel fibers can also reduce cracking, and improve the cracking resistance of concrete materials.
Properties of Concrete with High-Volume Limestone Powder as Composite Mineral Admixture
Authors: Song Shao Min , Wang Xiao Lun , Wang Lin
Published: August 2012

This paper studies the effects of high-volume composite mineral admixture made of limestone powder and low-quality fly ash on the properties of concrete. Through experiments, this paper makes clear the workability of fresh concrete and analyzes the law of strength development of concrete. The experimental results indicate that the concrete with high-volume limestone powder as composite mineral admixture has good fresh properties; due to low water consumption per unit volume, medium-and-high-strength concrete can be prepared. As new type concrete mineral admixture, the composite mineral admixture made of limestone powder and low-quality fly ash will play an active role in the sustainable development of concrete industry.
Preparation and Properties of MWCNTs/CF Reinforced Epoxy Resin Composite Patch
Authors: Song Wei , Li Chang Qing , Lin Lin , Chen Yang
Published: August 2012

Multi-walled carbon nano-tubes and carbon fiber reinforced epoxy resin (MWCNTs/CF/EP) composite patch was prepared by the route of hot-melt impregnation. The results of the mechanical properties shown that adding MWCNTs had made the tensile strength and interlaminar shear strength increased by 9.79% and 3.1%, separatively. It was detected using the ultrasonic non-destructive technique that the composite patch had a good interlaminar combination with no defects as obvious resin enrichment or insufficient gel content except for some slight stratification phenomenon in few parts. The high heat-resistance obtained by TG.
Study on the Desulfurization Gypsum and Steel Slag Blended Clinker-Free Cementing Material
Authors: Luo Hai Liang , Li Chun Sheng , Ye Yi Ting , Chen Fu Dan
Published: August 2012

Based on orthogonal test with steel slag and desulfurization gypsum as main raw material, mixed appropriate amount slag and compound addition a little of activator, we explored the slag dosage, the proportion of the combined admixture activator and the desulfurization gypsum dosage impact on the performance of clinker-free cementing material, such as strength, stability, standard consistency water quantity and setting time. The results showed that the best mix proportion of cementing material with slag content 40% and activator A:activator B is equal to 2.78:2.22. We explored the structure and composition of hydration products further more by micro-analysis, such as SEM, EDS and so on. We can found that the cementing material hydration products similar with hydration products of silicate cement. The cementitious material hydration with Afm crystal content increased significantly. The Aft crystal generated in early hydration(3d) gradually transformed into Afm crystal in late hydration(28d) ,and the structure becomes more dense.
Evolution of Various States of Water in Blended Cementitious Materials
Authors: She An Ming , Yao Wu , Yuan Wan Cheng
Published: August 2012

Low field NMR, as a nondestructure and noninvasive method was employed to study the evolution of various states of water in blended cementious materials added with fly ash during hydration from 1 day to 100 days. The relative content of water held in series of pores in cement matrix, e.g. capillary pore, mesopore and gel pore, was determined based on the quantitative relationship between transverse relaxation time, T2, and pore dimension. The results indicated that the relative content of chemically bound water was higher at long-term cure of 100 days compared with the neat cement paste. The water distributed in various pores was also influenced by the pozzolanic reactions between fly ash and calcium hydroxide. The gel water and mesopore water increased dramatically during the short-term age of 1 to 7 days in blended matrix, but then decreased gradually after 28 days, unlike that in pure cement paste. Due to the lower hydration degree in blended matrix, there was still amount of capillary water residual in paste to supply for the further hydration of fly ash.
Investigation on Asphalt Modified by LDPE Combined with Petroleum Resin
Authors: Li Jiu Su , Yuan Wen , Jia Wen Ke
Published: August 2012

The influence of combination of low density polyethylene (LDPE) and petroleum resin on asphalt was investigated by analyzing the change of its penetration, ductility, softening point and viscosity. The results show that petroleum resin can significantly increase the viscosity of PE modified asphalt, which results in the improvement of the asphalt’s waterproof ability and anti-rutting performance in a certain degree. However, the ductility and softening point were negatively affected due to the addition of the petroleum resin. Through analyzing the penetration indexes, an optimal dosage of 8% PE and 5% petroleum resin can be determined, respectively.
Towards the Climate Adaptive Residential Buildings Design
Authors: Chen Hong , Wang En Dong , Li Qiong
Published: August 2012

Climate adaptability of residential buildings is critical for their energy efficiency. This paper investigates the operable design methods dealing with residential climate adaptability on the basis of the general design principle and the conceptual design theory. Particularly, the impacts of wind forces on the ventilation environment and sunshine on the lighting environment for residential buildings are explored by combining qualitative analysis and numerical simulation under the perspectives of master plan and individual design, respectively. The corresponding alternative operable design schemes are presented through case examples to make buildings more adaptive to local climate.
Research on Application of New Energy-Saving Building Materials
Authors: Liu Ai Fang , Guo Shu Rong
Published: August 2012

Currently, energy saving and consumption reduction has been a crucial task the domestic people are facing with. It has been considered as essential question in the field of building materials to research and develop a new energy saving building material. In this paper, we classified new wall material and thermal insulation material, analyzed the performance, feature and application of such materials, selected typical foam concrete and slurry insulation material and analyzed their thermal properties and technology parameters and so on, to present the development trend and direction of energy saving building material, to provide valid scientific data to relevant building energy saving management units, design units and construction units, to play a positive guiding role in improving the application level of new energy saving building material and promoting new energy saving building material of high quality.
Effectiveness of Alkali-Activated Slag Cementitious Material as Adhesive for Structural Reinforcement
Authors: Zhu Jing , Zheng Wen Zhong
Published: August 2012

Alkali-activated slag cementitious material (AASCM), a high-temperature resistant inorganic adhesive, is presented in this paper. The components of AASCM were optimized for favorable mechanical properties. A FRP-to-concrete bond test to account for the influence of FRP and adhesive types was performed on thirty-three specimens. The results show that after the double shear tests, the interfacial shear strengths and reinforcing effects of AASCM are comparable to that of epoxy adhesive, and this strengthening method of strengthening concrete structures with CFRP sheets bonded with AASCM is feasible.
Rice Hull Ash Concrete Mechanical Properties
Authors: Sun Bo Cheng , Wang Shao Qing
Published: August 2012

This technical note discusses an innovative use of rice hull ash (RHS) as filler in concrete. RHS in the range of 0–30% was used as a partial replacement for ordinary cement in a concrete of mix ratio 1:2:4:0.6 (cement: sand: coarse aggregate: water cement ratio). Fresh concrete properties, compressive, split tensile strengths, and modulus of rupture were measured for concrete mixtures with RHS within the investigated replacement levels. The results showed that the setting times of RSH concrete increased with higher ash content, while the compressive, split tensile strengths and modulus of rupture showed a reverse trend.
Study on Low Temperature Performance Evaluation Index of Asphalt Mixture Based on Bending Test at Low Temperature
Authors: Lv Si Si
Published: August 2012

In order to characterize how the temperature influence Low Temperature anti-cracking performance and the ability of asphalt mixture resist low temperature, on the basis of bending test at low temperature, this paper from the angle of energy, introduce the concept of failure energy per unit volume as the evaluation index for the low temperature performance of asphalt mixture. Meanwhile, this paper used this evaluation index to perform bending test at low temperature for two kinds of different type of asphalt mixture which under three temperature as follows:0°C，-10°C，-20°C, And separately calculated failure energy per unit volume, then analyzes the characteristics and regularity of the index.
TG-FTIR Study on the Heat Treatment of Plasticized Melt-Spun PAN Precursors for Carbon Fiber
Authors: Yan Bin , Han Ke Qing , Zhang Jing Jie , Wang Dan , Liu Su Ping , Tian Yin Cai , Yu Mu Huo
Published: August 2012

In this paper, the evolution of the gas evolved during the heat treatment of the plasticized melt-spun PAN fibers was investigated by TG-FTIR. TG, DTG and G-S (Gram-Schmidt) curves showed that there were two main decomposition stages during the heat treatment of melt-spun PAN fibers. And the results indicated that the main pyrolysis products were NH3 (966 cm-1 and 932 cm-1), HCN (713 cm-1), H2O (3650 cm-1), CH4 (1305cm-1), CO (2180 cm-1), CO2 (2360 cm-1 and 667 cm-1). The release of NH3 and HCN started at the same temperature 220 °C, which were the main products during the stabilization step. Besides, the formation mechanism of the pyrolysis products is presented in detail.
Laboratory Assessment of Workability of Asphalt Rubber Hot Mixes Using Warm Mix Technology
Authors: Huang Meng Yun , Liu Jing Hui , Zhang Xi , Li Dan Ni
Published: August 2012

Using the waste crumb rubber modified asphalt to pave the road surface could reduce cost and save energy. However，in order to obtain adequate workability, the mixing temperature and compaction temperature of rubberized asphalt binder and its mixture is much higher than those of conventional asphalt mixtures. Warm Mix Asphalt (WMA) is the name given to certain technologies that reduce the production and placement temperatures of asphalt mixes. One of the main benefits advertised is the increased workability at conventional and lower compaction temperatures with the WMA addition. This paper evaluates whether there are any synergy effects of using warm mix technologies and Asphalt Rubber(AR) hot mixes. This paper summarizes a lab research to evaluate the workability of Asphalt Rubber hot mixes containing warm mix technologies. Both asphalt binder and asphalt mixture were evaluated and compared. The research suggests that combining WMA technology with Asphalt Rubber mixtures is a win-win.
Studay on the Anisotropy of Clay
Authors: Chen Lan
Published: August 2012

The development of stress-induced anisotropy in clay which was not only decided by the maximum stress endured before, but mainly lied on the stress route that reaching the maximum stress point of clay. The development or disappearance means of stress-induced anisotropy of normally consolidated clay, anisotropic consolidation clay and over-consolidated clay with different stress history are analyzed by experiments. Additionally, the effect of stress-induced anisotropy on deformation is also analyzed.
The Technology on Producing the First Class Plywood Using Fast Growing Eucalyptus Timber
Authors: Li Kai Fu , Xu Kai Meng
Published: August 2012

There were three key factors including glue quantity of veneer, hot-pressing time, hot-pressing temperature to be researched on the effect of plywood performance, which gave a effective conclusion about technology parameter. The results indicated that the three factors obviously were related to the bonding strength and ranked as hot-pressing time > glue quantity of veneer > hot-pressing temperature in sequence. The best groups for production technology were that glue quantity of veneer was 320 g/m2 with hot-pressing time and temperature of 1.2 mm/min and 135 °C respectively.
Preparation and Properties of Polyurethane Heat Insulating Building Materials Based on Lignin
Authors: Han Yan Ming , Qin Te Fu , Chu Fu Xiang
Published: August 2012

The synthesis of polymer materials from renewable biomass resources has attracted lots of attention. In this study, lignin based polyurethane heat insulating building materials were prepared from isocyanate and lignin polyol. Lignin was modified by polyethylene glycol and glycerol with 0.6% acid at 120°C to obtain lignin polyol containing reactive hydroxyl groups, and then polyurethane foams were prepared by the reaction between the above lignin polyol and isocyanate. Hydroxyl value of lignin polyol, gel time, apparent activation energy for polymerization, impact strength and thermal conductivity of lignin based polyurethane were investigated. The results showed that: (1) hydroxyl value achieved 397.0 mgKOH/g at temperature 120°C; (2) the apparent activation energy for lignin based polyurethane polymerization was 34.12 kJ/mol; (3) compressive strength reached 291 kPa with lignin polyol content 30%; (4) thermal conductivity was 0.02517 W/mK when lignin polyol dosage was 30%. It was detected that lignin could be used to prepare polyurethane heat insulating building materials in replacement of petroleum polyols.
Hydration Dynamics of Portland Cement Studied by Magnetic Resonance
Authors: She An Ming , Yao Wu , Yuan Wan Cheng
Published: August 2012

Hydration dynamics of Portland cement was investigated by low field NMR, a technique with advantage of continuous and nondestructure monitor. The transverse relaxation time, T2, and signals intensity arising from the physically bound water in paste were measured. Their evolution with the hydration time could be used well to describe the hydration dynamics. Three successive periods, comprising of initial period, accelerated period and steady period, were defined according the different rate of change. The reactions and mechanism for individual stage were disscussed based on the cement chemistry theory.
Integrated Application of Renewable Energy Technology in Building Energy Efficiency
Authors: Chang Jing Yi , Kuan Yean Der , Yao Chih Hsun , Chan Sheng Ching
Published: August 2012

During the average fifty or sixty years of building lifecycles, large amounts of energies are consumed at all stages, from the production of building materials, transportation for project constructions, daily use, and maintenance to demolition, in particular, the daily energy consumption of air-conditioners, lighting, and elevators. The main “energy saving indicator,” from among nine green building indicators, evaluates the electrical power consumption of air conditioners and lighting. The main evaluation items are building envelope heating load ratio, air-conditioner energy efficiency ratio, and lighting energy saving ratio. During evaluation, the promotion and application of renewable energy is encouraged by incentive factors. The development and use of renewable energy technology may improve energy utilization efficiency, maintain a balance of supply and demand, and reduce environmental pollution, thus, this study developed a indoor personal office system with 1KW solar energy and a 500W proton exchange membrane fuel cell (PEM fuel cell) as the power source, which is composed of LED indoor lighting, air fan, LED table lamp, notebook computer, printer, and acoustic equipment. Under continuous operations of 24h, this office system will generate 12kwh of electricity, which reduces 7.656kg of carbon dioxide output. If continuously operated for 1 year, it will generate 4,320kwh electricity, which reduces 2,756.16kg of carbon dioxide output. In addition, the side product water can be recycled as landscape water.
Use of CRT Funnel Glass as a Fine Aggregate in Self-Compacting Mortar: The Effect of Limestone on Pb Immobilization
Authors: Lairaksa Nirut , Moon Tony
Published: August 2012

End-of-life CRTs are classified as hazardous waste since the funnel glass component has a high Pb content. Alternative management of the glass is required due to the cessation of closed-loop recycling of CRT glass. This study aims to compare the feasibility of using CRT funnel glass as fine aggregates in a self-compacting mortar by addition of limestone to enhance the Pb immobilization. Sample mixtures of self-compacting mortar were prepared from Ordinary Portland cement Type 1 (OPC) with water/cementitious (W/C) ratio of 0.38 by weight, which contained 0, 20 and 40 wt% of Samsung CRT funnel glass ground to sizes smaller than 595 µm as a sand replacement. The sample with glass mixtures contained additions of 5, 10 and 15 wt% of limestone, ground to sizes smaller than 297 µm as a viscosity modifying agent (VMA). The samples’ flow ability was tested by V-funnel and Marsh cone. Pb-fixation in the samples was analysed by TCLP at 7 days and 14 days. The addition of limestone as a viscosity modifying agent improved flow ability in mixtures with CRT funnel glass, with the addition of 10 wt% limestone showing the highest flow improvement in V-funnel tests for both glass mixtures. CRT funnel glass utilized as sand replacement at 20 and 40 wt% showed Pb leaching results within the US EPA allowable limits. However, the addition of limestone reduced the Pb immobilization ability in mortars. A silica based VMA such as fly ash and rice husk ash should be used for these applications.
Evaluation the Heat Environment for Using Phenolic Resin as Heat Insulation Construction Material
Authors: Sung Wen Pei , Wu H.H. , Chen Ting Yu , Ou Wen Sheng
Published: August 2012

In this research, two buildings were constructed using phenolic insulation along with considerations of various experimental elements and condition. These environmental factors include natural ventilation, forced ventilation, the mist system, and shading. The results show that when the building is well insulated, the heat transported across the well is effectively prevented indicating that the phenolic resin is effective in insulating the building. Under full sunshine, the room temperature is 10 °C lower than the ambient temperature under full sunshine with the best insulation effect observed at 10:00 am. Shading will provide additional insulation effect to lower the room temperature by 3 °Cmore; the insulation efficiency can also be improved by ventilating the room. Results at 12:00 noon show that shading can effectively reduce solar radiation on the wall whereas force ventilation will carry away heat to reduce the room temperature. Shading will always be effective in reducing the room temperature by about 4 °C, and at 14:00, forced ventilation is the most effective in lowering the room temperature.
Full-Light-Aggregate Concrete for Structural and Thermal Insulating Wall
Authors: Li Cong Bo , Yin Su Hong , Wen Zi Yun , Zhou Xiao Hua
Published: August 2012

An optimal air-entraining agent was selected through a systematically experimental and theoretical study on air-entraining and full-light-aggregate concrete (AEFLC) for structural and thermal insulating wall. Among the three air-entraining agents: rosin acid sodium, Polycarboxylate-type agent, Lauric acid-based agent, Lauric acid-based (Huntsman) air entraining agent was considered the best for the air-entraining quantity and quality. As the result, a AEFLC with the apparent density of 1110kg/m3, compressive strength of 18.8MPa in 28 days, and thermal conductivity of 0.38w/(m.K) was obtained.
The Performance of Green Basalt Fiber and its Application in the Civil Engineering Field
Authors: Li Jian Jun , Meng Ying , Liu Yan Chun
Published: August 2012

By deeply analyzing and studying the physical and chemical properties of Lueyang’s basalt fiber, its characteristics such as the chemical components, the crystallization’s upper limit temperature and lower limit temperature during the melting process, and the the viscosity and temperature change during melting process are verified to provide theoretical bases for the industrial production of a new type composite materials, and meanwhile to offer grounds for the development of a new generation of composite fiber materials.
Research of the CFRP Strengthened Reinforced Concrete Structures
Authors: Wang Xiao Chu , Nie Hong Bin
Published: August 2012

This paper analyzes mainly that the CFRP reinforced concrete research and FRP cloth reinforced characteristics and advantages, and from the material aspects illustrate the CFRP cloth’s faults. For different components, materials, and the nonlinear programming and analysis, through the integral, combination, discrete type three calculation model of material and materials between, namely, concrete, steel, concrete and reinforced, GFRP cloth, concrete and CFRP cloth the constitutive relation analysis, this paper expounds the present research, points out the existing limitations of the present study and later the research direction. Finally, the paper draw the conclusion that the column and beam mechanical strength, toughness, and crack resistance, impact resistant properties and durability of these aspects to illustrate the superiority of the CFRP reinforced concrete. That fiber reinforced polymer (FRP) strengthening, repairing concrete has broad prospects for development.
Effect of Reinforcement Size on Concrete Crack Width with the Same Reinforcement Ratio
Authors: Shi Nan Nan , Huang Da Hai , Zhang Run Xiao
Published: August 2012

The quantitative influence of tensile steel bars size on the concrete crack width is analyzed. According to the engineering experience, the smaller diameter steel bars are superior to the bigger ones with the same reinforcement ratio consideration. However, the quantitative analyses have not been well treated. The criterion of “element with the maximum tensile stress will crack” and classic formula of the crack width in “Design code for hydraulic concrete structures”, are combined to analyze the uniaxial tensile specimens. Finally, three conventional diameters of tensile steel bars (14, 16 and 20mm) are adopted to verify the finite element model (FEM), and the quantitative analyses can be employed to the engineering reinforcement design.
Analysis of Failure Patterns and Damage Mechanisms under Impact Compression of Hybrid Fiber Reinforced Concrete
Authors: Chen Meng , Li Zhi , Lu Zhe An
Published: August 2012

In order to studying the failure patterns under impact compression of Hybrid Fiber Reinforced Concrete(HFRC), tests focused on static and dynamic compression properties according to steel fiber reinforced concrete(SFRC) and HFRC are adopted. The equipment of dynamic compression properties test is Ф74mm split Hopkinson pressure bar (SHPB). The static and dynamic compressive strength at four different strain rates of the two materials are obtained, while failure mechanism has been analyzed from specimens’ failure modes in static and dynamic compressive tests, which in turn provides theory basis for the application of HFRC.
The Influence of Engineering Pile on the Bottom Upheaval of Foundation Pit
Authors: Zhang Xi Zhen , Gong Quan Mei , Zhou Shun Hua
Published: August 2012

In foundation pit engineering, the presence of pile plays an important role on the pit stability and deformation control. The bottom upheaval of deep foundation pit is a key criterion of judging the foundation stability and deformation. This paper built the 3D finite element model to analyze the influence of different factors (pile diameter, pile length and pile spacing) on the bottom upheaval, and concluded that: when pile length and pile spacing is constant, changing the pile diameter can hardly affect the bottom upheaval; as the pile length increased, the inhibitory effect to the bottom upheaval grew stronger with a gradually decreased growth rate; increasing pile spacing can significantly reduce the bottom upheaval, and the smaller the pile spacing, the smaller the upheaval. The concept of upheaval inhibition rate was defined to evaluate the influence of different factors of pile layout on the bottom upheaval. A correction method of calculating the bottom upheaval of foundation pit with engineering pile was proposed. An engineering instance of Shanghai Natural History Museum foundation pit was studied, and the result showed that the bottom upheaval calculated by the correction method is less than the upheaval calculated by method of residual stress, which was more close to the monitoring data. The influence of engineering pile on bottom upheaval of foundation pit should not be neglected where a large number of piles were present in deep foundation pit.
Brief Introduction on the Application of High-Performance Concrete Preparation Technology in Ultra-High-Rise Buildings
Authors: Xu Li Bin , Ye Hao Wen , Feng Nai Qian , Bee Ch'ng Guan
Published: August 2012

With the constantly increasing height of the ultra-high-rise buildings in the world, the high pumping technology of high-performance concrete has become the feature of the constructions. This article has briefly introduced the preparation technology of the high-performance concrete in the world, then elaborated some key technologies such as the mixture ratio and mixture properties of high-performance concrete combining the West Tower project in Guangzhou Pearl River New Town (building height: 440.7m) contracted by Fourth Engineering Bureau of Chinese Construction.
Dynamic Analysis and Evaluation of Wind Turbine Towers
Authors: Chen Chang Zheng , Pan Ping Ping , Zhang Shi Wei , Qiang Meng
Published: August 2012

This paper presents static and dynamic analysis of wind turbine towers which is supporting a 1.5MW wind turbine based on the theory of FEM. In static analysis, the modal frequencies of the towers are analyzed without wind load. In dynamic analysis, by the fluid-coupling theory, the dynamic effect of wind loads on the towers is calculated. It can be concluded that the main errors under the different load situations is caused by the impact of fluid structure coupling.
Bearing Capacity Experimental Analysis on Slotted End Plate Connection Joints of Different Types
Authors: Yang Jun Fen , Li Hong Bo , Peng Yi Liang , Qiang Ruo Hui
Published: August 2012

Four different types of full-scale slotted end plate (SEP) connection joints are tested to determine their failure modes and damage mechanisms under ultimate load, also analyze their force-displacement behaviors and developing processes of deformation and stress. The results show that ultimate bearing capacity of the I-type SEP joint is only approximate 1/2 of the other three types of SEP joints, which indicate the SEP’s type have great influence on the ultimate strength of joints. The instability of SEP is the main factor to cause the loss of bearing capacity of the connection joints, which is shown through the development of stress, that SEP enters into plastic stage and the other regions still are elastic.
Research on Compression Failure and Size Effect in High Strength Eccentric Reinforced Concrete Column
Authors: Matamb Cedrick Mbang , Du Xiu Li , Zhang Jian Wei
Published: August 2012

This test was investigated on the compression failure in eccentric reinforced concrete square cross-section. In total twelve different scale specimens were eccentrically compressed with size of: 200×200mm; 400×400mm; 800×800mm. specimens were divided into 3 groups with 4 each. Only six columns have been investigated in this paper thus a column by eccentricity. The main point were based on the existence of size effect phenomenon on cross-section components collapsed with different sizes to the ultimate bearing capacity and the cross-section strain, ductility, deflection, and other failure characteristics. Analysis of the experimental data’s showed that the size effect phenomenon exists.
Modeling and Control of the Precision for the Building Energy Consumption Monitoring System
Authors: Zhao Liang , Zhang Ji Li , Liang Ruo Bing , Chen Yong Pan
Published: August 2012

Building energy conservation has become to be one of the major tasks of promoting energy conservation and raise the efficiency of energy consumption. Meters are the source of data, it is important to study data precision model based on the accuracy of the error analysis method. This paper firstly introduces error analysis, error distribution and error control theory, then take electric and heat meters for example to describe the error analysis and error distribute methods. The results show that when the precision level of voltage is 0.2, current is 0.2 and power factor is 0.5, the maximum relative error of electrical quantity can be controlled less than 1%, meet the requirement of measurement. The total relative error of heat meter is inverse proportion with temperature difference of sensor and water flow, and when the temperature difference remains unchanged, the error of heat meter trends to main steady if the instant flow of water more than half of the normal flow value.
Intelligent Prediction for Distortion of Weak Surrounding Rock in Tunnel
Authors: Huang Yuan Liang , Zhou Xin Wen , Liao Jiao Qi
Published: August 2012

In order to remove the hidden danger resulted by distortion of weak surrounding rock in tunnel, the GM(1,1) of the distortion data of weak surrounding rock is used to predict the distortion trend of weak rock vault in the next phase. According to the actual data, a GM(1,1) of the distortion is built, and it is shown that the predict result of GM(1, 1) is accurate, and the calamity can be reduced by the way.
The Safety Status Evaluation of Rock Mass Element by Nonlinear Mechanics Model
Authors: Zhang Hai Bo , Liu Qun Yi
Published: August 2012

Slope stability analysis is an important content in geotechnical engineering designing. And the safety factor is still the main index to evaluate the safety status of the whole slope, but the stability of each element of rock mass can not be reflected by the whole safety factor. Some scholars introduce the concept of point safety factor (PSF) to evaluate the stability of each element in rock-soil mass. However, the present work about PSF is remaining in the field of linear model, instead of nonlinear model. But in real situation, the nonlinear failure criterions are more adaptable used to describe the characteristic of rock mass, such as nonlinear failure characteristic of rock strength, structural characteristic and the effect of the stress to the strength of rock mass. So in this paper, the PSF based on the Hoek-Brown nonlinear mechanics model is founded, followed by calculation PSF for one rock mass element stability.
Dynamic Response of the Stay Cable under Bridge Deck Excitation
Authors: Luo Shuai , Liu Hong Jun , Yan Quan Sheng
Published: August 2012

Modeling the dynamic response of the stay cable under bridge deck excitation represents a complex task for cable design procedure and forms an important step in the cable mitigation design. This paper analyses the characteristics of cable response under bridge deck excitation. The problem of cable vibration under the harmonic oscillation of the supports is considered as the external excitation. The formulae for the estimation of maximum amplitude of cable vibration are presented to determine the main cause of large amplitude vibration of the cable under indirect excitation.
The Exterior Space Design of Public Rental Housing in Mountainous City of Chongqing
Authors: Gan Shi Yuan , Zhang Wei
Published: August 2012

The Public Rental Housing has been built large-scale ,it doing well in these respect in Chongqing ,such as balanced distribution ,convenience transportation, perfect mating, suitable living environment .But as a real mountainous city ,Public Rental Housing in Chongqing exist some problem in the incorporation between the exterior space and the geographical environment of mountainous city .The exterior space design didn't reflect the characteristic of mountainous city, it also lack of 3d stereo feeling, space distribution lack of identification feeling and characteristic , the acquaintance with special ground feature is not enough .Aim at above problems, come up with reasonable solution to increase the exterior space characteristic of public rental housing exterior space. Such as choosing the suitable living location, compiling with terrain, connecting ground in a suitable way, using various design way and so on.
Experimental Research on the Effects of Reinforcement Ratio on Axial Compression Properties of FRP Reinforced Concrete Column
Authors: Zhang Yun Feng , Lv Zhong Liang , Zhao De Wang
Published: August 2012

Through the axial compression experiment of 11 FRP reinforced concrete columns, this paper analyzes the failure mode and loading-strain curves.Comparison between the experimental data with FRP reinforced concrete and the calculated value without FRP reinforced concrete is done. The results show that the reinforcement for the component will increase ductility and ultimate bearing capacity of the composite column, but the increase of reinforcement ratio will also reduce confining ability of FRP tubes.
Study on Influence of Poisson’s Ratio on Bearing Capacity of Subsoil
Authors: Mei Ling , Zhou Ai Zhao , Jiang Peng Ming
Published: August 2012

The formulas of critical edge pressure and critical load are usually developed by assuming Poisson’s ratio equal to 0.5. It means that the soil be in a triaxial equi-compression state. This assumption increases the lateral load of subsoil, and makes the subsoil be in intensive state, and results in a higher bearing capacity of subsoil. In the paper, a MATLAB program is used to find the numerical solution of bearing capacity of soil with different Poisson’s ratio. This method corrects some calculating mistakes when proposes calculation formulas of subsoil bearing capacity which obtains Poisson’s ratio unequal to 0.5. And it compensates the limitation of some other calculation formulas. The influence of shear strength parameters of subsoil on critical load is analyzed.
Study on the Polyurethane Concrete for the Rapid Repairment of Highway Pavement
Authors: Wang Hui , Liu Hai Xia , Zhuang Cai Hong
Published: August 2012

Abstract：Polyurethane concrete which applies to the rapid repair highway pavement was systematically researched. Influences on mechanical properties of the polyurethane concrete of cement-dinas and binder-aggregate ratio, curing agent dosage, thinning agent dosage, etc. were analyzed in this paper. Furthermore, the optimal formulation materials were gotten to use in the repairment of used-broken cement blocks in the experiment. Simultaneously, the microstructure of polyurethane concrete and their adhesive situation bewteen waste cement blocks were observed through scanning electron microscope (SEM). The results show that the flexural strength of the specimen for two hours can reach to 6.67 MPa, and the compressive strength can reach to 9.15MPa, which can achieve the rapid pavement repair on highway in two hours, and it is superior to the related Chinese Standard. Besides the SEM images indicate that polyurethane molecular and aggregate are firmly bonded to each other as well as the cementation between polyurethane concrete and concretes, it means that the material has characteristic of rapid repair as well as good mechanical property.
The Low-Carbon City Construction Problems and Measures of Energy Scarcity Developed City in the Southern Jiangsu
Authors: Zhu Pei Feng , Zhang Hao
Published: August 2012

In order to deal with Energy scarcity and economic development problem, more and more city turns to the Low-carbon development model. The paper describes the Low-carbon city constructive condition of the Southern Jiangsu Province, and analyzes current main problems from the viewpoint of the industry, the traffic, the architecture, the consumer Low-carbon consumption consciousness and policy. After referring to experiences home and aboard，the paper puts forward some suggestions to deal with the before-mentioned problems.
Technology of Temperature Measurement in Concrete Bridge Pier
Authors: Wu Yun Fang , Zhang Zhi Yong
Published: August 2012

In order to accurately get the concrete pier temperature field, this paper briefly introduces the types, advantages and disadvantages, development of temperature sensors and the composition, function and measurement accuracy of LTM-8663 intelligent temperature monitoring system. The system has high measurement precision, so we can measure the temperature field by it. In order to certify the rationality of test methods, taking a concrete pier section model as an example, we use the system to measure its sunshine temperature fields in different ways of embedding sensor. According to the comparative analysis of sunshine temperature fields measured in pier section model, we get useful conclusions and recommendations to be provided references for the concrete temperature measurement in piers and other structures.
Based on Analytic Hierarchy Process in the Study of Cave Construction
Authors: Zhang Yin , Yang Hui
Published: August 2012

This article mainly study on AHP application in cave dwelling construction system, based on the combination with professional experience and the investigation of the folk, put forward the influence factors of building in caves, By establishing the hierarchical structure model ladder to explain the interaction of the various factors relationship，And then calculate and recognize the key factors in influencing of the cave-building, in the hope of improving the construction quality of a cave reference function.
The Highway Landscape Evaluation Based on Fuzzy Hierarchy Analysis
Authors: Shi Zhi Jian , Ge Wei , Meng Xiao
Published: August 2012

Two evaluation models AHP / Fuzzy AHP were discussed and used for integrated assessment of highway landscape evaluation scheme, by initial AHP calculation of the weight of highway landscape evaluation factors, followed by the judgment matrix fuzzy calculation and evaluation. The results indicated that the more objective and scientific evaluation can provide a new method to evaluate highway landscape.
Analysis of Failure Mode of Masonry Wall under Vertical Compressive Stress
Authors: Zhao Hui Hui , Zhang Wen Fang
Published: August 2012

The application of ABAQUS finite element software non-linear finite element analysis of brick masonry walls with structural column. Build three brick masonry wall models, and analysis of the damage form of the wall under different vertical compressive stress and horizontal force. Thus the analysis result compared with the calculation result of the relevant specification formula, in order to get validate compression influence of masonry aseismic walls. It turned out that different vertical compressive stress effect the shear capacity, and failure mode of brick masonry wall structure with a structural column.
Research on Advanced Geological Prediction in Highway Double-Arch Tunnel Construction
Authors: Tang Shuang Mei , Lin Chun Jiao , Yao Xiao , He Chong Xiong
Published: August 2012

In this paper, a comprehensive advanced geological prediction method in highway double-arch tunnel construction was put forward, which could take the advantages of geological radar technology and the horizontal of advanced drilling in karst area. The method would give relatively accurate judgments in the construction of the highway double-arch tunnel by using different geological radar survey line layout, combining with advanced horizontal hole, which ensure the construction safety of the tunnel. The practical application of comprehensive advanced geological prediction in double-arch highway tunnel in karst area had received a good effect, and it showed the method had a certain guiding function.
Experimental Study on Creep of Surrounding Rock Mass in Argillaceous Soft Rock Tunnel
Authors: Fan Qiu Yan , Lu Jia Yan , Zhu Zhen
Published: August 2012

Due to the complexity of underground engineering, study on creep characteristics of surrounding rock mainly adopts laboratory simulation experiment. Recently, the similar materials are used to do the experiment both at home and abroad, yet it can't reflect the original nature and others of rock fissure in original rock mass. Through the field collection of undisturbed sample of Tertiary mudstone, the conclusions are made by laboratory model test on surrounding rock of underground tunnel and creep process regularity and failure mechanism in the surrounding rock in this paper as follows: there are three obvious stages of creep under certain stress levels, which is measured on the surface of surrounding rock mass in argillaceous soft rock tunnel--decay creep ,steady creep and accelerated creep. The surrounding rock will produce the accelerated creep damage when the stress level is over a threshold value. Creep damage of surrounding rock mainly includes the forms of roof sinking, floor working up, and forming a macro- fracture surfaces etc. Test results showed that the undisturbed surrounding rock fracture would be dissimilar to the homogeneous surrounding rock without fracture in damage model, and original fissure have a larger effect on creep damage of surrounding rock.
Experiment Study on the Phenomenological Model of Bolted Joint Connections
Authors: Yang Min
Published: August 2012

Based on phenomenological method, the paper carried out experimental study for a kind of typical bolted joint structure, three kinds of testing specimens was designed, from the test result, the phenomenological model was obtained and the nonlinear mechanics behavior was comprehended, at last, the phenomenological model was verified experimental and numerical
Calculation of Shear Capacity of Steel Reinforced Concrete Beams Strengthened with Near-Surface Mounted CFRP Rods
Authors: Chen Wei Hua , Wu Mei Qin
Published: August 2012

Some calculated methods of shear capacity of RC beams strengthened with NSM(near-surface mounted) CFRP(Carbon fiber reinforce polymer) rods are reviewed based on the experimental data on shear capacity of RC beams strengthened with NSM CFRP rods. Therefore, according to the destruction forms of steel reinforced concrete beam strengthened with NSM CFRP rods, the formula for calculating the shear capacity of the beam is given. The formula is expressed clearly, simple and easy to use.
Principle of Stress Rate in the Instability of Trusses
Authors: Du Wen Feng , Yu Fu Dong
Published: August 2012

How to judge the dynamic instability of trusses is an important problem. It is found that stress rate of a truss has the catastrophic characters when trusses are out of stability. According to the relationship of the total strain energy and the stress rate, the principle of stress rate is proposed , that the dynamic instability was made in structures if the stress rate was suddenly changed to a relative very great value. Some examples, such as a dome shell, a three-bar spatial frame, a plane truss, and so on, are discussed. The results showed that it was effective to judge the instability of truss structures by using the tress rate criterion. By comparison of the stress rate criterion with the displacement criterion it can be obtained that the result of displacement criterion was comparatively obvious in the global instability while the result of stress rate criterion was more ocular in judging the local instability in truss structures.