bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure Design and Control for Multifunctional Paint-Device
Authors: Geng Jin Liang
Published: October 2014

In view of the traditional way of painting by using brush, wearing protective clothing and breathing harmful gas, etc. problems, The bottleneck of traditional manual approach to health, safety and social progress should be solved. By analyzing the relationship between innovative structure, strength analysis, recycling of resources and environmental protection,A comprehensive solution is put forward which includes the structure design of quadruple adjustment and twofold recycling, integration of roll-spray, automatic control and frequency conversion for speed regulation. The results of the enterprise’s practical application indicate that this device is effective on ensuring human health, environmental protection, resource utilization, improving productivity and creating economic benefit, Its market application prospect is very broad.
Analysis of Time Series to Wear Tendency of Aero-Engines
Authors: Jin Xing
Published: October 2014

A common method of debris detection to detect the condition of the engine is to establish the relationship between wearing condition and the elements in debris. To accomplish this aim, the ARIMA and Auto-Regressive models should be set up by analyzing the original time series which is established in accordance with the data of debris. After that, the trend of engine wear in a cycle of overhaul can be verified and the best model can be found depending on the situation of real data of debris. So the original time series can be obtained and the time series model to monitor engine condition can be set up. This paper finally provides a reference for monitoring engine conditions and other familiar fields.
A Corporate Computer Network Security System Design and Implementation
Authors: Jiang Lan
Published: October 2014

With the rapid development of economy and society, the growing prosperous computer network technology has now become one of the indispensable elements in human life. Small to every household personal computer systems, large to computer systems concerned countries, they are incorporated into the scope of computer network security systems. Enterprises are social living cells, with important role of financial intermediation, the mining technology and training personnel. Corporate computer systems is an important part to ensure high-speed operation of enterprises, summarize business information and protect trade secrets, therefore, the more developed computer network technology is, the more important the development and maintenance of corporate computer network security systems is. This article will explore the design and function of enterprise computer network security system implementations based on the characteristics of computer network security and enterprise computer network system.
A Fast Method of Motion Errors Compensation for High Squint Millimeter Wave SAR
Authors: Wang Quan , Wang Chao , Cui Kai Bo , Wu Wei Wei , Yuan Nai Chang
Published: October 2014

High squint millimeter wave SAR can be applied in missile-borne imaging seeker, but it’s very sensitive to the motion errors. Both the high squint SAR imaging algorithm and the motion errors compensation method are very important for achieving well focused SAR image. Therefore, a motion compensation method integrated with the imaging algorithm is proposed. Firstly, the expression of instantaneous squint range is given according to the imaging geometry model of high squint SAR. Then, the components of motion errors are separated and estimated, using the parameters of inertia navigation system (INS). Finally, the envelope and phase corrections are performed in high squint SAR data through the obtained motion errors. The effectiveness of the proposed approach can be verified by the imaging results of measured millimeter high squint SAR data.
A New Approach for Developing Crossword Games
Authors: Zhang Hong Tao , Gao Jin Yan , Sun Qing Jie
Published: October 2014

This paper puts forward a creative idea that the tiled map editors can be used to replace specialized editors in the development process of crossword games, and this has been verified in a complex Chinese crossword game project. The final results prove the idea completely feasible. This indicates the development process of casual games can be greatly accelerated with appropriate tools and targeted data structure design.
A Synthetic Approach for the Preparation of P1-AZT-5′-P3-d4T-5′-Triphosphate
Authors: Gong Shan Shan , Sun Qi
Published: October 2014

A novel and efficient method for the preparation of P1-AZT-5′-P3-d4T-5′-triphosphate has been developed. The title compound was characterized with 1H, 13C, and 31P NMR and mass spectrometry. The experimental results indicated that the employment of 4,5-dicyanoimidazole (DCI) as the activator could notably promote the coupling reaction of AZT 5′-phosphoropiperidate and d4T 5′-diphosphate.
Quality Detection Techniques and Assessment Method of Highway Projects
Authors: Luo Xiao Jia
Published: October 2014

The foreign and domestic detection techniques of highway project are described firstly in this paper.Then the author analyzes the detection techniques of flatness,deflection and ground penetrating radar (GPR), and starting from the current national laws and regulations.This paper,in the light of current national laws and regulations, mainly discusses the quality assessment of highway projects from aspects of evaluation requirements,evaluation process and evaluation methods.I.Trace to the source of Detection Techniques and Assessment method of of Highway Projects
Architectural Research with Initial Exploration on New Chinese-Style Landscape Design Method
Authors: Wang Yang , Chen Yan
Published: October 2014

With the increasingly distinct pursuit of traditional culture by the public, the new Chinese-style landscape will be a development trend with constant improvement, playing a motivated role in a city, even a country. This paper conducts an analysis on the related concept and elements of new Chinese-style landscape and proposes the design methods of new Chinese-style landscape, to create a new design featuring the period feel and sense of nationality, with better integration and inheritance between tradition and modernity.
Research on Mechanical Conditions of Vehicle Rollover at Corners
Authors: Qian Kai Guo
Published: October 2014

Vehicle rollover refers to a dangerous lateral movement of a vehicle in contact with the ground when it rotates around its longitudinal axis to a certain angle degree or greater angle during moving. There are many factors that could cause the vehicle's rollover, including automotive structures, road conditions and the driver's condition. vehicle rollover can be divided into two categories, one category is tripped rollover (trPPiedorllover), the other is a rollover (maneuve curve caused by motion: niduecdorllove) The former refers to the generation of lateral slip when the vehicle is moving, and the obstacle on the road surface collides sideways with it its "tripped" The latter refers to the rollover caused by the vertical reaction force inside the wheels of the vehicle reaching to zero because sideways acceleration of the has exceeded a certain limit when the vehicle moves on the road (including a lateral ramp). In this paper, only the rollover caused by curvilinear motion will be studied.
Energy Optimal Control of Induction Motor for Electric Vehicle Drive System Base DTC
Authors: Yu Hong Xia , Qiao Jing Shi
Published: October 2014

The requirements of the drive system for electric vehicle is high efficiency and fast dynamic response, an optimal control method base direct torque control is proposed to improve respose speed of energy optimal controlled induction motor. In stator flux orientation coordinate system, the loss mathematical model of the induction motor was established by analyzing the relationship between loss and motor torque, speed and stator flux, then the optimal stator flux formula is derived under different operating conditions to achieve the maximum efficiency of induction motor, the getted optimal stator flux is used as stator flux set value in DTC. Simulation results reveal that the proposed method improve the efficiency and respose spee of induction motor.
Design of Automotive Intelligent Preloaded Safety Belt
Authors: Zhao Yu , Guan Zhi Wei , Du Feng
Published: October 2014

This paper introduces the significance of automotive safety belt, designs intelligent preloaded safety belt system. The system is made up of early warning sensors, seat belt furl system and core controller based on the MC9S12DP256. This article focuses on the structural optimization and circuit design of the controller. The designed test-bed is able to predict the dangerous occurrence and control the safety belt tightening through processing early warning signal of the sensor, implements the safety belt active preload function and meet the needs of active safety.
Synthesis and Property Analysis of Hydrophobic Modification Guar Gum
Authors: Chen Feng , Wang Xu Guang , Yang Ren Shu , Yu Man Lin , Wang Qiang
Published: October 2014

The experiments were conducted to study the property of HMG GG-C14 which was prepared by pre-swelling guar gum hydrophobic modification in alcohol-aqueous solution, and the experiments results show the better viscosifying property of this hydrophobic modification product, and indicate that the novel hydrophobic modification method has better modification effect.
Research on Method of Process System with Error Tracing Based on PSO
Authors: Yao Yi Yong , Wang Xu , Diao Guang Zhou
Published: October 2014

In machining process, the machining systems are usually described by the stable theoretical model. However, there are still various process errors existed. To recognize, compensate and eliminate the errors, a method of process system error tracing based on PSO is proposed to explore the errors existing in the machining process. The determined theoretical model is defined and actual measurement data samples are used to find the optimal solution, get the deviation value of each error sources. Finally, the process system error tracing of the Arc Cam is taken as an example to prove the stability and validity of proposed method.
The Design of Automatic Control System for Industrialized Recirculating Aquaculture
Authors: Liu Yu Qing , Wu Yan Xiang , Cao Li Ling
Published: October 2014

Based on the control process and requirements of the industrialized recirculating aquaculture system (IRAS), we designed an aquaculture automatic control system. The entire system is divided into seven modules including water circulation and filtration, bioreactor self-loop, water quality monitoring, Emergency treatment, thermostatic temperature control, PID operation, and failure alarm. It is used to control the water circulation, and automatically detect and adjust the environmental factors of the pond for best farming environment. The lower computer adopts Siemens S7-200 PLC. MCGS configuration software is applied in the upper computer for the dynamic display, parameter setting, fault alarm and other functions of the whole recirculating aquaculture process. The lab test showed the advantages of the system including the high degree of automation of the system, user-friendly, easy to maintain and reliable operation, with a good promotional and application value.
Research on the Single Target Recognition of Car Collision Avoidance Radar Based on the FMCW Technology
Authors: Zhao Shuang , Chen Lei
Published: October 2014

The signal processing algorithm mainly for the FMCW automotive collision avoidance radar is studied in this paper. Through discussing the FMCW signal processing works with two-dimensional FFT algorithm, we use CZT transform to refine the velocity spectrum so as to accurately extract the velocity of the target.
Generic and Automatic Multi-Channel Control System
Authors: Zhang Xiao Yu , Wu Yuan , Mo Chong Jiang
Published: October 2014

This document mainly describes the control equipment of microwave anechoic chamber RCS measurement system, which can be expanded into a generic and automatic multi-channel control system. The conventional control equipment is mainly operating in manual mode with computer control feature as secondary. Such feature causes the problems of difficult operation, complicated structure and no software portability. This generic control system is designed with DAM-E3000 series of module which is an interface module from generic sensor to computer, uses remote Ethernet connection solution, supports TCP/IP and UDP protocols, and can realize remote I/O control. This generic control system has the automatic control feature through network by using this mentioned module. In addition, the hardware structure design is simplified, and the software portability and expandability are enhanced, so that the codes programming difficulty is lowered. Therefore the system can conform to more industrial I/O signal protocols and can be used widely in various industrial environments.
Reliable Data Transmission Scheme Based on Network Coding in Wireless Sensor Network
Authors: Niu Tao , Zhuang Yi
Published: October 2014

In order to achieve reliable data transmission in clustering structure based data acquisition systems of wireless sensor network, in this paper, we propose a reliable data transmission scheme based on network coding for clustering wireless sensor network. We use random linear network coding to solve reliable multicast data transmission from base station to other nodes, and then combine random linear network coding with multipath routing for transmitting acquired data to the base station, so as to improve the success rate for sending acquired data to the base station. Simulation results show that the proposed algorithm can achieve reliable data transmission with lower energy, and significantly improve the transmission reliability compared to data transmission without using network coding.
Research on Information Processing with Dynamic Adaptive Job Scheduling Algorithm Based on Hadoop Platform
Authors: Jiang Xue Ying , Wang Yao , Meng Yan Yan
Published: October 2014

Job scheduling and resource allocation problems relate to the overall performance and resource utilization of Hadoop platform. This paper proposes a dynamic adaptive job scheduling algorithm based on Hadoop platform. This algorithm monitors the change of each computing resource nodes in real time. And through the feedback mechanism pass this information to the control node. It implements the purpose of assign the optimal resource for each of tasks.
Chaotic Clonal Genetic Algorithm for Routing Optimization
Authors: Fan Bing , Zeng Ying , Tang Liang Rui
Published: October 2014

Clonal operator which can reserve the elites is introduced in the selection step of traditional genetic algorithm (GA) to accelerate the local convergence speed. Chaotic search which is randomness and ergodicity is applied in crossover and mutation operators to avoid the algorithm stopping at a local extreme value. The above hybrid GA is called chaotic clonal GA (CCGA) which can overcome the instability of optimizing processes and results in traditional GA by the certainty of chaotic trajectory. The CCGA is applied to solve the problem of load balance routing in differentiated service networks. The routing optimization model is created and the optimizing objective is load balance and small path length. The simulation results show that CCGA has fast convergence speed and high stability. It can meet the requirements of important business routings.
Research on Applied-Information Technology Based on the Improved NCC Identification of Fruit and Vegetables
Authors: Zhuang Lu Lu , Wang Yan Qing , Zhang Zhen Wei
Published: October 2014

NCC algorithm for the shortcomings, namely the operation is slow and does not have a real-time. Through multi-valued by differential summation and template matching methods for NCC to improve , it enhances the computing speed of the algorithm and adaptive algorithm. Through lots of experiments to prove, using improved NCC to identify fruits and vegetables, The algorithm has good recognition of fruits and vegetables and has robustness and real-time performance.
Research on Applied-Information Technology in Online Compact System Based on Serial Communication
Authors: Jiang Hong
Published: October 2014

The ceramic industry fall into two main categories: daily used ceramics and craft ceramic. With the demand for daily used ceramics is increasing in my country, ceramics enterprises are faced with intense market competition. Based on the investigation of ceramic industrial production, the traditional method for Ceramic production has some disadvantages, such as long periods of dies production, complicated production process, wasting human resource, high cost, short life, poor quality, easy to damage. According to the characteristics of daily used ceramics, this paper presents a rapid prototyping system based on RS-232C compacts. This system can cancel the long and complex development process of the dies, and can achieve rapid prototyping of ceramic body, thereby greatly reducing the cost of production of ceramic manufacturers.
Applied-Information Technology in Random Naming System Based on Image Processing and Application
Authors: Zhou Xiao Xiong , Yan Tao
Published: October 2014

The traditional class naming is take time, the effect is not good, and there will be many take another's place by counterfeiting phenomenon, So, this paper proposes a random naming system based on image processing. This paper establishes the database class students, including students some basic information, such as name, student number, photos; then establishes a random roll call system, which the teacher can random name evaluation, for students grades and attendance; finally, test system and further improve . Because the roll call to show the students the image clear based on image processing , avoid take another’s place by counterfeiting phenomenon, student performance improved significantly. The test results show that the random naming system we developed, convenient for teacher to student's attendance and can improve student the attendance.
Research on Data Processing in PLM Product Based on Cloud Platform
Authors: Peng Wei Ping , Zhong Yuan Hua , Liu Zhao , Li Jing , Gao Rong
Published: October 2014

To solve the problem of massive PLM product data analysis, a PLM product data analysis system based on OpenStack cloud platform was proposed.It includes a data analysis method of structured products based on data warehouse and a data analysis method of non-structured products based on Hadoop. By means of the former method, firstly product data was filtered, tranformed and loaded into the warehouse, then the required data cube was extracted, lastly the structured product data was analyzed with the analysis tools of data warehouse. By means of the latter method, the product data firstly was loaded into the distributed file system,and the non-structured massive PLM product data was analyzed by the data mining algorithm,which was programmed by JAVA language based on MapReduce. By applying the methods mentioned above to massive PLM product data analysis, it shows that these methods hava a higher efficiency.
Applied-Information Technology in Project Portfolio Risk Management System Based on Hall's Three-Dimensional Structure
Authors: Wu Yun Na , Liu Chao , Xu Hu
Published: October 2014

Project portfolio management involves multiple projects, of which risk regulation is different from the risk regulation of single projects especially in information technology application. In addition to considering each project's own risk, it must consider risk of project portfolio from a broader perspective. Issues of risk regulation are more complex, therefore its risk regulation requires new management approaches. This paper draws on Hall's three-dimensional management structure, respectively, from the four aspects: project portfolio management process, project portfolio risk regulation process, project portfolio risk regulation approach and project portfolio risk regulation organization, to establish a project portfolio risk regulation four-dimensional system (tlkc system) by applied-information technology. It provides a theoretical guidance for current risk regulation of project portfolio management, contributes project-oriented enterprises to establish suitable project portfolio risk regulation measures with their own circumstances, which is a necessary complement for project portfolio theory.
Data Processing in Project Supply Chain Vendor Selection Based on Improved Entropy Weight - Grey Correlation - TOPSIS
Authors: Lu Qiu Qin , Zhao Qiao
Published: October 2014

On the basis of the establishment of evaluation index system, an improved entropy weight – grey correlation – TOPSIS model is put forward to select project supply chain vendor, and process the related data. The each index weight is obtained from subjective weighting method and objective entropy method. The positive and negative distance between each evaluation object and ideal solution is calculated, and the grey correlation grade between each evaluation object and ideal solution is obtained. Then the relative closeness of each evaluation object can be gained that we can select the best vendor according to it.
Data Processing in Scientific Research Performance Evaluation of University Based on DEA and Supervision Measures
Authors: Wu Yun Na , Yuan Jian Ping
Published: October 2014

The university scientific research performance has being a hot issue in recent years. The scientific research performance evaluation of university is one of important bases for rationally allocating educational resources. Data processing is very important for evaluation. This study analyzes many factors that affect the university scientific research performance to collect evaluation indicators for data processing. The collected indicators are classified into input indicators and output indicators. Then Factor Analysis is used to reduce the number of two types of indicators with professional software SPSS. Further, the selected 32 universities are evaluated on research performance by using DEA method. Finally, the results of scientific research performance of university are obtained, and the improvements and supervision measures are proposed.
Application of Forecasting Power Based on Neural Network and Wilcoxon Rank Sum Test
Authors: Tian Zhi Peng , Xia Chang Hao , Chen Jian Ping
Published: October 2014

With the development of modern power systems, the accuracy requirement for load forecasting is getting higher and higher. In this paper, the Wilcoxon rank sum test as a new mathematical method to test error, is applied to the neural network based short-term load forecasting model. The actual historical load data and the associated weather conditions factors to be considered, based on MATLAB neural network toolbox, The method to construct three different neural network model, the power load in Yichang area in 2009 was forecasted and the simulation of short-term. The simulation results show：Wilcoxon rank sum test algorithms in neural network model, not only can correctly predict，relative to the average relative error, in the statistical methods and statistical laws - especially in the face of large amounts of data - through a random sample to show a certain advantage in the overall distribution.
Study and Application of the Life-Cycle Cost Control Model of Water Conservancy and Hydropower Project Based on Entropy and FAHP
Authors: Wang Chun Yan , Wei Ning
Published: October 2014

How to implement the life-cycle management of water conservancy and hydro power project cost effectively, and how to distinguish the influence degree of different factors on project cost stage management. This is a key problem in project cost control. In this paper, based on the influence of each factor on the overall evaluation goal influence, FAHP is applied to set up Fuzzy Comprehensive Evaluation Model. Aiming at the variability characteristics of factors in each stage, the information entropy is used to determine the objective weight in the model, in combination with AHP the subjective weights to determine the weight.
Mechanical Properties of Reactive Power Concrete and Ultra-High Strength Concrete with Coarse Aggregate
Authors: Yang Juan , Peng Gai Fei
Published: October 2014

An experimental investigation on the variation of compressive strength, splitting tensile strength and fracture energy, with the ratios of water to binder (W/B) of ultra-high strength concretes, including the reactive power concrete (RPC) and ultra-high strength concrete with coarse aggregate (UHSC), has been carried out. The W/B varied between 0.14 and 0.22 at a constant increment of 0.02. It was observed that, compressive strength of RPC almost remained the unchanged, when the W/B was between 0.14 and 0.18. However, it decreased dramatically when the ratios were 0.20 and 0.22. For UHSC, the compressive strength was the highest value at the ratio of 0.18. The results of the two concretes could not comply with the Abrams' generalized W/B ratio law. Moreover, splitting tensile strength of RPC and UHSC decreased continually as the ratio increased from 0.14 to 0.22. Fracture energy of RPC was more or less the same when the ratios were between 0.16 and 0.20, and the maximum value was at 0.14. Fracture energy was observed to be almost no variation for UHSC at all ratios
Application of Micro-Structure Testing in the Analysis of the Cause of Concrete Cracks
Authors: Chun Chen , Zhang Ya Mei , Wang Rui Xing , Yang Jie
Published: October 2014

Scanning electron microscope, differential thermal analysis, thermo-gravimetric analysis, fluorescent analysis and X-ray CT et.al. have become usual means used in the research of concrete material science. This paper proposed a new method to evaluate the causes of cracking of in-situ concrete based on the investigation by using these comprehensive technologies for analysis of micro-structure. The proposed new method is more reliable and objective than the traditional method which is mainly based on experience and chemical analysis. A case investigation using the new method to explore the causes of cracking in a real project was introduced.
Evaluation of Shrinkage Resulted Cracking of High Strength Calcium Sulfoaluminate Cement Concrete with Impact of Internal Curing
Authors: Luosun Yi Ming , Zhang Jun , Gao Yuan
Published: October 2014

In this paper, restrained ring test and shrinkage test are carried on three kinds of concrete—high-strength portland cement concrete, high-strength calcium sulfoaluminate cement concrete and high-strength calcium sulfoaluminate cement concrete with internal curing in order to evaluate the shrinkage induced cracking performance of the concretes. The experimental results show that calcium sulfoaluminate cement concrete exhibits lower shrinkage caused by surface drying comparing to portland cement concrete. Internal curing can eliminate most of the autogenous shrinkage of concrete. In the ring test, the latter two concrete did not crack during the whole test history—42 days, while high-strength portland cement concrete cracked at the 13th day after casting. High strength calcium sulfoaluminate cement concrete exhibits better anti-cracking ability than the high strength portland cement concrete with the same strength grade.
Experimental Research on High-Strength Super Sulphate Cement Paste Mixed with Superfine Mineral Admixtures
Authors: Wang Jun , Yu Bao Ying , Yang Long , Gao Yu Xin , Xiang Jia Yu
Published: October 2014

Aimed at the performance affect of high-strength super sulphate cement (SSC) paste mixed with superfine mineral admixtures, influence of microbead and silica fume replacing SSC quantity on high-strength SSC paste compression strength were studied under water-cement ratio 0.18; Hydration product morphology and phase were further compared by scanning electron microscopy and X-ray diffraction analyzer in this paper. Results show that, compared with sample HS-1, 3-day strength of HS-2 and HS-3 were increased by 5% and 10%, 28d strength basically unchanged; Furthermore, early strength of HS-7 sample slightly higher and late strength basically unchanged. SSC by adding 5% microbead and 3% silica fume (HS-11) has compressive strength 50.8MPa at 3 days and 86.1MPa at 28 days is significantly higher than other samples. Early strength of HS-11sample mainly depends on hydration reaction of SSC and particle filling effect of admixtures, later strength is due to accelerating consumption of gypsum and promoting formation of ettringite.
Material and Structural Properties for Creating High Performance Concrete Structures
Authors: Balázs György L.
Published: October 2014

HPC and UHPC concretes are finding their ways both to new structures and to retrofitting of existing structures. Herein specific material properties as well as structural examples are discussed. New Codes and Recommendations provide description of material properties and design rules for HPC/UHPC structures and structural elements.
Behavior of High Performance Steel-Fiber Concrete Exposed to High Temperature in Terms of Spalling and Permeability
Authors: Peng Gai Fei , Duan Xu Jie , Yang Xue Chao , Hao Ting Yu
Published: October 2014

An experimental investigation was conducted on behavior of high performance steel-fiber concrete subjected to high temperature, in terms of explosive spalling and permeability. A series of concretes incorporated steel fiber at various dosages were prepared, and further processed to have a series of moisture contents. Explosive spalling tests were conducted on control plain concrete and steel fiber concrete. After explosive spalling tests, each of the specimens that didn’t encounter spalling was sawn into two pieces. Crack observations and permeability tests were conducted on the sawn surfaces. The results prove that steel fiber is efficient to avoid spalling concrete under high temperature. The permeability increases significantly after thermal exposure, while it also exhibits an ascending trend with the increase of moisture content. Therefore it is concluded that steel fiber can play a positive effect on explosive spalling of high performance concrete under high temperature, as well as on permeability after thermal exposure.
Research and Application of Multi-Properties Concrete
Authors: Feng Nai Qian , Ye Hao Wen , Lin Zhong Long
Published: October 2014

Multi-properties concrete (MPC) contains the properties as follows: self-compacting, self-curing, heat dissipation at low water content; low shrinkage; high plasticity keeping and high durability. We applied the concept of “multi-properties concrete” (MPC) during the construction of the West Tower and East Tower both at Guangzhou and Jinji Complex at Shenzhen. The multi-properties concrete is more effective in controlling cracks of concrete, while it is a new type concrete with properties of green and low carbon.
Mechanical Properties of Recycled Aggregate Concrete at High and Low Water to Binder Ratios
Authors: Peng Gai Fei , Wang Shuo , Li Ting
Published: October 2014

This paper presents an original research on the influence of defects in recycled aggregate (RA) on mechanical properties of recycled aggregate concrete (RAC), including compressive strength, splitting tensile strength, fracture energy and elastic modulus. Six types of concretes, with the water to binder ratios (W/B) of 0.26 and 0.60, were prepared using nature aggregate (NA), RA and recycled aggregate treated by 3 mol/L (RA-H). Mechanical properties of RAC was inferior to that of NAC, and treated RA by sulfuric acid solution could improve the mechanical properties. Attached mortar in RA was the main factor resulting in the decrease of mechanical properties of RAC with 0.26 W/B, and for the RAC with 0.60 W/B, the effect of aggregate damage was more significant than that of attached mortar.
Study on the Calcinations of Recycled Cement Clinker Using Waste Concrete and Waste Clay Brick
Authors: Ai Hong Mei , Zhu Su Feng
Published: October 2014

Utilizing construction waste, mainly waste concrete, to produce recycled cement, provides possibility for realizing the closed circulation between concrete and cement, which is an effective way for sustainable development of cement and concrete industry. Waste clay brick (WCB) and its surface-coated waste mortar are inevitably introduced into the raw meals while waste concrete is used in cement production. So on the basis of the composition characteristics of construction waste, considering of optimizing the performance of recycled cement and improving the adaptability of recycled cement to complex raw material, it's necessary to study the effect of raw meal mixing waste concrete and WCB on sintering process and property of recycled cement clinker. Mixing waste concrete and WCB in three different proportions, the burnability of raw meal, clinker mineral composition, clinker mineral morphology and hydration characteristics of recycled cement have been studied in this paper. The results indicate, the presence of WCB is beneficial for the generation and development of silicate minerals; with increasing proportion of WCB, the content of f-CaO in recycled cement clinker rises, the structure of C-S-H gel from hydration product presents higher densification and the compression strength of 3d and 28d curing period are enhanced.
Experimental Study on Non-Autoclaved PHC Pile Concrete Applying Polycarboxylate Superplasticizer
Authors: Zhan Ying , Yang Yi Bo , Wu Xiao Huan , Xie Yu Hang , Luo Jian , Guo Wen Ying , Hao Yan Hao , Wang Heng Chang
Published: October 2014

Traditional PHC pile production adopts two-step curing with the disadvantages of high energy consumption, considerable carbon emissions, and easy cracking during construction. In addition, non-autoclaved pipe pile studies involve problems such as adoption of naphthalene based superplasticizer and lengthy coated curing duration, thus leading to their few applications. In order to solve the problems, the study on non-autoclaved PHC pile was conducted to systematically study the impacts of curing system, water-binder ratio, and admixture composition on concrete strength, ratio of tensile and compressive strength, and chloride ion resistance at different ages. Study results show that through the use of a polycarboxylate superplasticizer, an optimal 8-hour curing system and concrete mix ratio, the strength of non-autoclaved concrete reached 93.2MPa within one day, with the ratio of tensile and compressive strength of 6.07%, the coulomb electric flux of 85C, and the chloride migration coefficient of 0.54×10-12m2/s.
Effect of Fineness on the Properties of Cement Paste
Authors: Li Hua Jian , Yang Lu , Xie Yong Jiang
Published: October 2014

Properties of cement paste were affected significently by fineness of cement which is one of the most important influence factors. Effect of fineness on the rheology properties, strength, hydration and pore structure of cement was studied. The results showed that: plastic viscosity of the cement paste can be reduced by the increase of cement fineness to some extent. The strength of cement, especially the early strength significantly increased; heat of hydration increased, the peak of hydration heat brought forward and induction period shortened; porosity of cement paste reduced with the increase of cement fineness. There is a good negative linear correlation between characteristics particle size D (0.1) and 1 day hydration heat of three different kinds of cement. Keywords: cement; fineness; hydration; porosity
Evaluation and Application of Recipe for Binding Materials in Self-Compacting Concrete
Authors: Yeih Wei Chung , Chang Jiang Jhy , Chi Mao Chieh , Chang Cheng Chin , Huang Ran
Published: October 2014

Concrete consists of many kinds of raw materials, the safety and quality of construction are greatly influenced by the stability of concrete. Thus, how to improve the performance of concrete and construction method, i.e. avoid the bleeding, segregation and honeycomb, etc, becomes a very important issue and imminent mission. This study discusses the different mixing designs of SCC with the amounts of cementitious materials ( OPC, GGBFS, and FA) ranged from 400 - 500 kg/m3. Meanwhile, the fresh and hardened properties of SCC, such as the slump flow, setting time, heat of hydration, and compressive strength were also determined. Test results indicate SCC binding materials can be classified by its compacting ratio. For instance, to pass the boxing test of R1/R2 within and without hindrance, the minimum binding materials should be 500kg/m3, 450kg/m3 and 400kg/m3. The optimum binding materials research shows if use cement, GGBFS and FA at the same time , it can increase the initial and final setting time and decrease the heat of hydration. The SCC binding materials’ concept will meet the requirement of " Safety, Durability, Workability and Ecology " for the new era. Thus, the amount of cement was at least 250kg/m3 or more for SCC mix design and the adding of GGBFS and FA was recommended to maintain 20 - 40 % of all cementitious materials based on the test results.
Research on the Application of Expansive Agent in C60 Self-Compacting Concrete
Authors: Lin Xi Qiang , Li Guo You , Huo Liang
Published: October 2014

It analyzed the performance, mechanical properties, volume stability, microstructure of hydration cementitious material of C60 self-compacting expansion concrete, which dependent on CSA to expansive ettringite source for the expansion. Results suggest that on the same curing conditions, C60 self-compacting concrete with the water-cement ratio of 0.32 admixture CSA expansive agent can effectively control the shrinkage of concrete, so that it is slightly inflated. The dosage of CSA expansive is higher, early strength of C60 self-compacting concrete is lower and its late strength declines small. It is affected little for the slump and extended degree of concrete under the superplasticizer by the expansive agent. SEM results show that CSA expansion agent can improve the pore structure of hydrated cement paste system with low water-binder ratio. The gel phase after hardening has good compactness and ettringite needlelike crystals mostly distribute at each interface layer.
Effect of Colloidal Nano-Silica on the Mechanical and Durability Performances of Mortar
Authors: Du Hong Jian , Pang Sze Dai
Published: October 2014

s. The mechanical and durability properties of cement mortars with colloidal nanosilica (CNS) were investigated experimentally. Reference mortar with a low water-to-cement ratio of 0.30 was used in this study. The influence of CNS was evaluated by adding 0.5, 1.0, 1.5 and 2.0% of CNS by weight of cement. CNS was first stirred in the mixing water for 2 minutes before added to cement and sand. Superplasticizer was used to maintain the same flowability. Results showed that the compressive strength consistently increases with higher dosage of CNS at all the curing ages, due to both hydration acceleration and pozzolanic reaction. With the increase in CNS, the migration coefficient and water sorptivity consistently decreased; with 2% of CNS, the migration coefficient and water sorptivity were reduced by 45% and 30% respectively in comparison with the reference mortar. The improved durability could be explained by the reduction and refinement in the porosity, which can be attributed to nanofiller effect and pozzolanic reaction of nanosilica. Furthermore, the addition of CNS could reduce the drying shrinkage by densifying the microstructure in the cement paste, which has not been reported previously.
Reuse of Waste from the South West of England in Alkali-Activated Cement Concrete
Authors: Zografou Adamantia , Heath Andrew , Walker Peter
Published: October 2014

The extraction of china clay in the South West of the UK generates waste in a mass ratio of 1:9 for china clay: waste. Currently, part of the coarser waste, “stent” and sand named “china clay sand” (CCS) in this study, is used as building stone or secondary aggregate in concrete and asphalt but the finest waste fraction, called “mica” waste, is used only for the restoration of old quarries. Looking for innovative solutions for the needs of a new Eco-town in the UK, and with regard to uses commercially applicable to construction and of low environmental impact, the china clay waste is being studied as an aggregate in alkali-activated cements (AAC). Aiming to replace primary aggregates with wastes in low risk construction materials, a series of AAC concrete based on a 50% GGBS and 50% fly ash (FA) blend and an equivalent Portland concrete series were produced. In the mixes the primary aggregate was steadily replaced by forms of the waste and tests in compression showed a decreasing trend in strength accordingly. The two series of concrete follow approximately the same ratios of decrease although in absolute values the AAC series reached higher range of strengths on the 28 day compared to the Portland series. While the use of CCS did not have any negative impact, the addition of mica decreased the strength up to 25% more.
The Research of Mud Influence on Properties of Concrete
Authors: Hang Mei Yan , Lan Ying Jing , Zhang Pei Yu , Zhang Li Ming
Published: October 2014

Abstract: The same amount of mixture ratio of cement, replacing a part of fly ash with a certain amount of mud to research about the workability of fresh concrete and the effect of the mechanical and shrinkage properties of hardened concrete. Test's results show: The different kinds of mud lead that the fluidity of the fresh concrete and the strength of hardened concrete are different. The influence of sand mud is lighter than planting mud on the fluidity and strength of concrete. The compressive strength of concrete decreases and the early shrinkage increase with an increase of mud replaced the fly ash.
Research Progress on Carbon Nanotubes Reinforced Cement-Based Materials
Authors: Wang Bao Min , Liu Shuai , Han Yu
Published: October 2014

For their remarkable properties, carbon nanotubes (CNTs) are considered as promising candidate for next generation of high performance and functional cement-based composites in 21st century. The paper focuses on the dispersibility, mechanical property, durability, conductivity and piezoresistivity properties of CNTs reinforced cement-based materials. A homogenous CNTs-suspension was obtained using the method which combined ultrasonic processing with mechanical stirring, electric-field introduction and surfactant decoration. The low weight fraction of CNTs improved the mechanical properties of CNTs/cement composites. The compressive strength and toughness were correspondingly improved. The added CNTs improved the sulfate attack resistance and impermeability properties of the prepared CNTs/cement mixes. Meanwhile, the added CNTs improved the pressure-sensitive, conductivity and electromagnetic absorption properties of the prepared mixes, which laid a foundation of multi-functional concrete and structure. It concludes that the key issue for CNTs/cement composites is the dispersibility and the compatibility of CNTs in cement matrix. The solving solutions are put forward. In the meantime, the further research prospects in this research field are forecasted.
Self-Healing and Repairing Concrete Cracks Based on Bio-Mineralization
Authors: Qian Chun Xiang , Luo Mian , Ren Li Fu , Wang Rui Xing , Li Rui Yang , Pan Qing Feng , Chen Huai Cheng
Published: October 2014

In this paper, three bio-mineralization mechanisms were proposed to repair cement-based materials cracks. The common feature is that the three are all induced by bacterial. A type of bacterial which can decompose urea and release carbonate ions could be applied to repair micro cracks on concrete surface when combining calcium ions. But what need to be noted is that the way of repairing cracks is passive. Some alkaliphilic bacterial spores could be added to concrete when casted and two different types of bacterial were used to realize the function of self-healing. The sources of carbonate ions made them different, the one release carbonate dioxide through its own cellular respiration, the other could transfer carbon dioxide in air to bicarbonate. Coefficient of capillary suction, apparent water permeation coefficient and area repairing rate were applied to characterize the repairing effectiveness. The tests results were that all three bio-mineralization mechanisms showed excellent repair effect to small cracks formed at early ages. When the bacteria were immobilized by ceramsite, the self-healing effect could be improved for the cracks formed at late ages.
Scattering-Filling Stone Concrete: Mechanism, Experiment and Utilization
Authors: Shen Wei Guo , Yang Zhen Guo , Yang Zhi Feng , Li Jiang Feng , Cao Liu , Zhang Chuan
Published: October 2014

The coarse aggregate volume fraction in conventional plastic concrete is controlled relatively low to ensure a required workability, but its low aggregate content play negative roll on the service properties of the concrete. In this paper, we revealed the mechanism of a coarse aggregate interlocking concrete prepared by Scattering-Filling Stone Concrete (SFSC), it can keep the fresh concrete its workability but increase its service performance by scattering coarse aggregate during the concrete casting, the experimental and engineering application of SFSC indicated that: the strength of concrete prepared with this method increases obviously whereas the shrinkage decreases significantly when 20% cement dosage is saved. The SFS process was utilized in a highway pavement, the core of the concrete is very dense and no obvious defect could be found when 8% pavement concrete was replaced by coarse aggregate. The SFSC is a type of low carbon concrete.
Reinforced HSC Beams
Authors: Elbasha Nuri Mohamed
Published: October 2014

The primary long and short term advantages of high strength concrete are, low creep and shrinkage, higher stiffness, higher elastic modulus, higher tensile strength, higher durability (resistance to chemical attacks) and higher shear resistance. In addition, high strength concrete reduces the size of the member, which in turn reduces the form size, concrete volume, construction time, labor costs and dead load. Reducing the dead load reduces the number and size of the beams, columns and foundations. Thus there is a positive impact on reduction of maintenance and repair costs and an increase in rentable space. Other, yet to be discovered advantages may also exist. High strength concrete has definite advantages over normal strength concrete. The ductility of over reinforced HSC beams is enhanced through the application of helical reinforcement located in the compression region. The pitch of helix is an important parameter controlling the level of strength and ductility enhancement. This paper presents an experimental investigation of the effect of helices on the behavior of over reinforced high strength concrete beams through testing ten helically confined full scale beams. The helix pitches were 25, 50, 75, 100 and 160 mm. Beams’ cross section was 200×300 mm, and with a length of 4 m and a clear span of 3.6 m subjected to four point loading. The main results indicate that helix effectiveness is negligible when the helical pitch is 160 mm (helix diameter). The experimental program in this study proved that the HSC, HSS and helical confinement construct a reinforced concrete beam. This beam has the ability to resist weathering action and chemical attack while maintaining its desired engineering properties. In near future Reinforced High Strength Concrete Beam with Helical Confinement will be considered as a durable and sustainable Reinforced Concrete Beam.