bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling Concrete Strength Using Support Vector Machines
Authors: Yang Hai Ying , Dong Yi Feng
Published: October 2013

Support vector machine (SVM) is a statistical learning theory based on a structural risk minimization principle that minimizes both error and weight terms. A SVM model is presented to predict compressive strength of concrete at 28 days in this paper. A total of 20 data sets were used to train, whereas the remaining 10 data sets were used to test the created model. Radial basis function based on support vector machines was used to model the compressive strength and results were compared with a generalized regression neural network approach. The results of this study showed that the SVM approach has the potential to be a practical tool for predicting compressive strength of concrete at 28 days.
Problems and Effective Countermeasures in Construction Safety Management
Authors: Shuai Li , Li Hong
Published: October 2013

With the rapid development of construction industry progress, construction safety is paid more attention by more and more people. At present, construction safety has become the main problem which restricted the construction industrys development. It not only reflects construction enterprises management level, but also the economic efficiency of enterprises. Therefore, adopting prevention measures about construction industry is worth researching and discussing. This paper introduces the present situation of safety management in construction sites, then analyses the major safety management problems. Finally, it pertinently advances effective countermeasures on the basis of Safety First, Prevention First, Comprehensive Treatment to achieve the aim at reducing the construction safety accident rate to the greatest extent.
Applicable Strategy on Energy Saving Optimization in External Wall of Rural Residence Based on Low Cost and Low Technology
Authors: Lu Mei Jun , Li Hu
Published: October 2013

Based on the situation of residential construction, economic characteristics and construction technology in rural region, the design idea on energy saving optimization in rural residence based on low cost and technology is formed. On this basis, combining the characteristics of rural residential construction and the current economic situation in rural areas, applicable strategy on energy saving optimization for external wall in winter cold and summer hot regions of rural residence is put forward, which contains increase of wall thickness, using insulation layer with different thickness for each orientation wall, adopting applicable thermal insulation materials and doing heat-insulating design for west wall. The strategy has good popularization value in winter cold and summer hot regions.
Research on Construction Supervision Progress Control during Equipment Installation Phase
Authors: Yang Yan Yan , Feng Jiao Wei , Yuan Ying Bao
Published: October 2013

The project progress control during equipment installation phase is a weak link in the whole construction process, and also the important and difficult part for supervision unit to implement the progress control. From the perspective of supervision unit, this paper analyzes the main factors affecting the progress control during equipment installation phase. Base on the analysis, some countermeasures and suggestions are put forward.
Study on Effect of Different Fine Aggregates on Properties of Dam Concrete
Authors: Li Ren Jiang , Zhu Zheng Gui , Yao Xian Hua , Zhang Xiao Yan
Published: October 2013

The effect of different water absorption and texture of fine aggregate on properties of dam concrete is significant. This paper studies the properties of dam concrete made by the same and different kinds of fine aggregates. The results showed that concrete made by fine aggregate with high water absorption have higher degree of hydration, larger workability, lower ultimate tensile strength, compared to concrete made by limestone sand. Concrete made by basalt sand have lower strength, higher dry shrinkage, lower autogenously volume deformation.
Research on Energy Saving Reconstruction Strategy of Rural School Building in Guanzhong Area - A Case Study of Guocun Primary School in Xi'an City
Authors: Yang Zhi Xiong , Ma Ting , Huang Jie , Liu Yu
Published: October 2013

As an important component of the construction of a new socialist countryside, the rural school building is the important infrastructure of new rural cultural construction. This paper takes rural schools of Guanzhong area as research object, combining the geographical environment characteristics with social development conditions to field investigate, and analyzes rural school construction and its status in Guanzhong area. On the basis of the investigation and analysis, this paper points out the advantages and disadvantages of design and usage of the existing rural school buildings, and proposes energy-saving strategy which is suitable for rural school building.
Simulation Research of Qingdao Green Building System Based on System Dynamics
Authors: Xun Zhi Yuan , Zhao Tai , Cao Ning
Published: October 2013

With the increasing deterioration of the resources and environment, the development status of construction industry which based on high pollution and high energy consumption need to be changed urgently. So it is imminent to develop green buildings. Aimed at the complexity and systemic of the green building development process, this paper analyses the relationship of the feedback elements at all levels. The main factors affecting the green building system are analyzed by using the basic methods of system dynamics. This paper also establishes the simulation model of Qingdao green building on the basis of system dynamics and forecasts the development trend of green building in Qingdao by simulating the model in computer.
Application of the Last Planner System in Schedule Management of Construction Projects
Authors: Jin Jun Yan
Published: October 2013

Schedule control is one of the main tasks of engineering project management, and effective schedule management is an important means of realization of project objectives. The traditional project schedule management is lack of dynamic adjustment and update, and various drawbacks of the method have been appeared. Last planner system (LPS) is a kind of schedule management of project based TFV theory of lean thinking, which transfers the traditional "push" system into "pull" system for schedule management. Based on the master schedule, look-ahead schedule and weekly work plan, schedule management with LPS will facilitate the realization the projects schedule objective.
Land Value Evaluation of Real Estate Development Project Based on Grey Correlation Analysis
Authors: Wang Wei Ran , Sai Yun Xiu , Fang Xing
Published: October 2013

The accuracy of land value directly affects the size of the project development profit in real estate development project, more will be related to the project success and failure. According to the characteristics of the real estate development, land prices in the mature real estate, on the basis of influence factors, the grey correlation analysis model is set up by using the value of developed successful plot, to estimate the land value, and combined with examples to provide a reference for scientific decision-making to real estate developers.
Study on Employer's Cost Control in the Bidding Phase
Authors: Wang Qiu Fang , Liu Xing , Li Juan Fang
Published: October 2013

Bidding stage is one of the important stages of cost control of project construction, which is a form of beforehand control and active control. In order to make rational use of construction funds and pursuit investment returns to a greater extent, the employer should strengthen the construction cost control in the bidding phase. To begin with, this paper analyzes the significance of construction cost control in the bidding phase, states the form of expression of construction cost in the bidding phase, and focuses on the analysis of influence factors of cost control in the bidding phase. Finally it puts forward some countermeasures to prevent the risk of project cost control in the bidding phase.
Non-Utility and Redundancy of Modern Architectural Space
Authors: Lin Lin , Tang Jian , Yu Ling
Published: October 2013

Redundancy has penetrated into literature, art, architecture and many other areas with the arrival of redundancy era, which significantly impact on architecture. This paper discusses the important role of redundant space, also called non-utility space, in architecture from four dimensions of philosophical view within redundant space, material and spiritual value of space and serving as medium space, using a philosophical way of taking architecture as part of historical events.
Difficulties and Countermeasures on Restricting the Development of Project Management
Authors: Luo Qin
Published: October 2013

Difficulties of engineering supervision are mainly in the complex beneficial relationship among the owner, supervision and contractor. Owners lack of knowledge on the need of supervision and uneven quality of supervision personnel bring about disjunction in the stage of decision making, design and construction during the project operating process. The measures can be used to introduce a new mechanism to eliminate the economic dependence between the supervision unit and the owner, enhance the construction of laws and regulations in supervision, improve the three main competitive consciousnesses and ability of the construction market, and strengthen the engineering and construction market regulation.
The Impact of Urban Land Reserve System on House Prices
Authors: Yan Rui Jun , Xu He Fang
Published: October 2013

In recent years of China, land reserve system has become a vital measure of urban land system reform, it also has been a hotspot of the reform for real state territory. Starting from the land reserve, this paper will research the changes of house prices after land reserve occurs, and reveal how the land reserve makes effect on house price.
The Development Plan and Countermeasure of Affordable Housing in Hainan Province
Authors: Yi Jun , Wen Chang Zhong
Published: October 2013

Under the premise of the rapid development of housing in the whole country, Hainan Province as the only an international tourism island, the affordable housing development has been got a wide concerns and high evaluation by the provincial government. But in the process of rapid development, there are still some problems to be solved. This paper analyzes the main problems in construction and management of affordable housing in Haikou, Hainan Province, and puts forward corresponding countermeasure according to the Twelfth Five Plan about affordable housing.
Numerical Simulation of Smoke Movement in Vertical Shafts during a High-Rise Building Fire
Authors: Zhang Xu Tao , Wang Song Ling
Published: October 2013

A numerical study on the smoke flow in a shaft, representing the stairwells, the elevator shafts and warehouses, is conducted during a high-rise building fire. It is of vital importance to predict the movement of smoke throughout the tall structure, because smoke is the major and leading cause of fatalities. The stack effect takes place due to the temperature differences between the smoke in shafts and the environment. The cold air enters in at a lower opening and exhausts at a higher ones, and this leads to the concept of the horizontal elevation called the neutral pressure plane, where the air flow equals zero. The location of neutral plane plays a key role on the management of smoke. The numeral results obtained with the FDS (Fire Dynamic Simulator) illustrate how the smoke movement can be managed in order to mitigate dangerous conditions within the structure.
Research on Materials for Construction Projects Cost Control – Taking a Project in Shijiazhuang as an Example
Authors: Yu Xiang Mei , Geng Dong Yang , Xie Zhen Bin
Published: October 2013

Through referring to practical projects and analyzing the component proportion ratio of project cost, this paper comes up with the idea that whole process of construction project is all around material management as the key of cost control, puts forward the measures to reduce material costs, and offers reference to cost management of construction project.
Study on Application of Tubular Truss Structures in Engineering
Authors: Zhou Ji Jian
Published: October 2013

This paper mainly focuses on the application of the large-span tubular truss structures in engineering. Taking a 60 meters cross-connections tubular truss with sliding supports used at one end of a cultural center project as an example, the problems of free vibration and optimum design of the structure are discussed in detail. The outcomes of this paper provide some reference for the design and construction of the congener structure
Analysis and Comparison of Different Confined Concrete Models
Authors: Yu Ping , Zhang Qin , Yang Li , Gong Jin Xin
Published: October 2013

Different confined concrete models and their influences on column lateral load-deformation relations are compared and studied in this paper. The analytical results show that models have remarkable discrepancies on the descending branch of constitutive curves, and these discrepancies are weakened in predicting of column lateral load-defromation curves due to eccentric compression of confined concrete.
Structures under Multi-Hazards: State-of-the-Art and Research Needs
Authors: Liu Yong Jun , Wu Yao , Zhou Jing Hai , Wang Yu
Published: October 2013

Recent years, many infrastructures, say building structures and bridge structures, have suffered from multi-hazards. According to official reports, 286 fires broke out due to the 2011 off the Pacific coast of Tohoku Earthquake, and fire after 1995 Kobe earthquake destroyed almost 7000 buildings. Current design codes treat earthquakes, fires and explosions as completely independent. The application of multi-hazard design is essential for improving the safety of structures, reducing building life cycle costs and increasing efficiency. In this paper, some influential multi-hazard incidents are described primarily, and the state-of-the-art and research needs on multi-hazard design are presented.
Detection and Identification of a Building after Fire
Authors: Yang Xue Rui , Ran Qun
Published: October 2013

This article based on detection and identification of a building after fire, to introduce the scene investigation contents and methods in detail, through the analysis of test results to evaluate the damage of structure, then puts forward comprehensive appropriate disposal suggestions, to provide reference for the detection and identification of construction after fire in future.
Studies of Anti-Disaster Ability of the Plate Truss Structure
Authors: Feng Jiao Wei , Lu Jun Yan , Ma Jin Dong
Published: October 2013

The grid structure often overall failed dut to local damage under the disaster load. In order to avoid the situation, the load cases of the plate truss structure under vertical load are analyzed in this paper. Taking the measure of strengthening the important bars, the ultimate bearing capacity of the structure is improved significantly. The improved load bearing capacity plays a positive role in resisting exceeding loads. Anti-disaster ability of the structure is improved.
A Discussion on Causes and Preventive Measures for Construction Quality Accident
Authors: Sun Yun Ting , Li Hong
Published: October 2013

A long lasting project, quality is priority. The quality directly determines the success of project. The excellence of a building quality is not only the pulchritude of a countrys construction, but also the guarantee of safety of life and wealth. However, due to non-standardizing of construction market and disarray of internal management, the quality accident often occurred. This paper, based on engineering practice in projects, analyzes causes for common construction quality accident from design, materials construction supervision and some other factors, puts forward some typical engineering examples, and offers corresponding preventive measures to reduce the occurrence of construction quality accident.
Computational Study of Wind Effect on Window Flame Spread across the Exterior Wall of High-Rise Building
Authors: Li Jun Mei , Yin Chen Chen , Hu Cheng , Li Yan Feng , Xu Peng
Published: October 2013

The fire in high-rise buildings is perhaps more dangerous than those occur in normal buildings because of the strong stack effect and wind effect on the fire. The wind effects on the wind flame spread across the exterior wall of the high rise building are studied in this paper by the numerical methods. The results show that high wind speed will change the wind flame spread direction and make the room inclined above the fire room more danger, especially the room at the same floor adjacent to the fire room. Special passive fire protection measures should be taken under these kinds of conditions.
A Evolution Model of the Express Freight Network
Authors: Yang Zhen Yu , Ge Zheng Yi
Published: October 2013

A Evolution Model of the Express Freight Network is proposed based on the evolution theory of complex weighting network. The freight demands and space distance are considered into the preferential attachment scheme. Applying the model on the evolution of the express freight trains service network by China Railway Express, results show that the model is capable to embody the evolution laws with some indices slightly better than the real network.
Different City's Short-Term Housing Prices Affect the Relationship from Empirical Analysis in China
Authors: He Yuan , Shi Ya Kun
Published: October 2013

According to the city development level and the regional difference, selecting 10 main cities of China and using the monthly average date of house price about three years, the effect of relationship between cities prices of different levels of development and the region in short-term was studed through the unit root test by using the method of VAR analysis model and the pulse and variance. The results show that, the rate of increase in housing prices in China between different city in short-term are clearly linked, the changes of overall level of first-tier cities affect the more rational second-tiers housing prices next period, which has a significant influence on the second-tier city to the same regions three-tier city next period. The impact of China's city structured relationship in housing prices is figured out.
Research on Application and Development of the Building Life-Cycle Management in China
Authors: Feng Bin , Hua Yang , Zhang Jian Zhong
Published: October 2013

The construction industry, as a traditional Chinese industry, its information construction level is obviously lower than other industries. In order to enhance construction productivity and reduce resource consumption, construction industry must be done for informational reform. The Building Life-cycle Management (BLM) and the Building Information Model (BIM) contain the abroad forerunners technique of establishing and managing construction information, which realize the whole process management of the construction item and whole life span of the information. This paper introduces the basic circumstance of BIM and BLM technology, analyzes the technique of BIM and BLM in the opportunity of the Chinese applied expansion, and puts forward the problem being faced and the motive to be pull.
Human Factors Analysis and Model of Accidents due to Driver Errors
Authors: Lu Wan Wan , Jiang Xiu Shan , Bi Jian Bin
Published: October 2013

On the basis of human factors analysis of driver error accidents, this paper establishes the accident-causing index system due to driver errors and puts forward the use of trapezoidal fuzzy hierarchy - the grey correlation analysis method to analyze the accident-causing index model due to driver errors. Then this paper uses related data and proposed analysis method to obtain the weights order of accident-causing factors. The results reveal the main cause of accidents due to driver errors, and provide the reference for further research to prevent the traffic accidents.
Research on Budget Control at the Stage of Municipal Road Design
Authors: Cao Li Jun , Geng Dong Yang , Yu Xiang Mei
Published: October 2013

With the rapid development of economy, the investment of municipal road construction project also has a quick growth. Design phase is crucial that determines the cost of a construction project. Stage of the project cost only ensure the timeliness and accuracy in order to manage the whole process of the project cost in the effective control of project cost of the occurrence, and improve investment returns and social benefits. This paper studies the budget control in design phase of municipal roads.
Study on Quality Evaluation System for Arterial Highways Based on Fuzzy Comprehensive Evaluation
Authors: Li Jie , Yang Shao Wei
Published: October 2013

In this paper, the preliminary study of fuzzy comprehensive evaluation for arterial highway is made, the multi-level evaluation index system is set up, the process and formula of fuzzy comprehensive evaluation are proposed, and the practical application is explained by examples. To evaluate the highway engineering feasibility study, some methods are applied such as fuzzy comprehensive evaluation, analytic hierarchy process, expert evaluation method, etc. Thus it provides objective evaluation for the related management department to achieve the goal of improve the quality of highway preliminary work.
Study on the Applicability of Grading Speed Limit Programs in the Highway Construction Operation Zone
Authors: Yu Ren Jie , Zhu Hong , Ma Rong Guo , Liang Guo Hua
Published: October 2013

The grading speed limit programs were simulated under different traffic conditions by using traffic simulation software VISSIM, the applicability of grading speed limit programs in the highway construction work zone were studied, the value of each applicability assessment indicators was drawn, and the values were evaluated and compared comprehensively by a weighted addition ratings method. The results indicate that the degree of the applicability of each grading speed limit programs is different, and they have different impact on safety and traffic efficiency of highway construction work zone.
Research on Grading of Risk Factors in International EPC Projects from Contractors' Perspective
Authors: Li Ji Qin , Yang Yong , Zheng Yu , Li Xiao Dong
Published: October 2013

t has been common that more and more international projects are contracted using EPC mode, which brings higher requirements of risk management for Chinese engineering companies. Through literature research and expert interview, this paper systematically recognizes and classifies risk factors that may occurred in international EPC projects. Then, by applying AHP method, the weights of all risk factors are achieved. Furthermore, all risk factors are divided into three levels for the convenience of enterprise risk management. Hopefully, this research can be good reference as guidance for decision-making in the preliminary stage of international EPC projects.
Period-Doubling Bifurcation of Logistic Model Using Nonlinear Controller
Authors: Ouyang Ke Jian , Xie Guo Sheng
Published: October 2013

The period-doubling bifurcation of logistic map is effectively controlled by designing nonlinear controller, and the bifurcation maps of the dynamics system which are in the dominate of nonlinear controller are compared with thoes are not in the dominate of controller. The result show that the choice of controller in an advisable way will make the effect of bifurcation control tally with the anticipative purpose by computer numerical simulation.
Study on Delivery of Perishable Products in Retail Enterprise's Distribution Center
Authors: Wei Fei , Ge Zheng Yi , Zhang Zhi Wei
Published: October 2013

According to the delivery situation of perishable products in retail enterprises distribution centers, considering a service time limit, the paper establishes a model and applies max-min ant system to solve vehicle scheduling problem with hard time windows to minimize distribution costs of perishable goods. Besides, the paper uses a case to demonstrate the feasibility of this model.
Risk Evaluation Index System for Operation Security in High Slope Construction on Freeway Reconstruction and Extension
Authors: Hu Qing Guo , Xie Wang Xiang , He Zhong Ming
Published: October 2013

The risk evaluation index system for operation security in high slope construction was drawn up on the basis of characteristics analysis of operation security, combined with expert evaluation and fuzzy prioritization method. The evaluation index system includes four factors of geological conditions, operation environment, slope construction and traffic organization, which lays the foundation for correct evaluation the influence of high slope construction to operation security.
Consistency Checking Based on Ontology of Design Information
Authors: Liu Yun
Published: October 2013

This paper aims the ontology consistency to detect and identify potential conflicts and contradictions in the BIM design process, to improve the efficiency of the coordination and communication between engineers in departments. The information of building design such as concepts, nature, requirements, restrictions, etc., can be standardized by the ontology using a computer language, basing on which, consistency is detected. This paper describes the process that conflicts or contradictions are identified in the BIM design and modified to restore the process.
Research on the Application of Ground Source Heat Pump Technology in Timber Structure
Authors: Bian Zhi Hui , Wang Tie Cheng , Zhao Shi Yong , Guo Xian Fa
Published: October 2013

Ground source heat pump technology is a new type technology of superficially geothermal utilization. By taking Chinese-Canadian cooperation in the energy-saving low-carbon environmental demonstration housing project for example, this paper is to introduce the low-ground heat used in the timber structure. Through analysis of the energy consumption on the integration technology for wooden structure and ground source heat pump, and compared with conventional energy on energy consumption, validated applying renewable energy sources on modern wooden structure will produce significant benefits on economic and environmental, which possesses significant role in promoting that creating a resource-saving and environment-friendly society.
Study on Multi-Vehicle Refrigerated Distribution of Agricultural Products with Soft Time Windows
Authors: Li Feng Xu , Yang Yue Fang , Wei Fei , Wei Feng
Published: October 2013

To the distribution status of agricultural products, this paper proposes a multiple-type vehicles refrigerated distribution route optimization model with soft time windows, innovatively considering that different type vehicles have different marginal and travel costs, and applies genetic algorithm to solve it. Finally, this paper uses an example to check the model, and proves that the model is feasible and effective.
Study on the Impact of Inner Anchorage on Waterway Traffic Capacity
Authors: Wang Wen Yuan , Tang Guo Lei , Guo Zi Jian , Song Xiang Qun , Du Peng Cheng
Published: October 2013

As the number of calling ships in container terminals rises, waterways in some harbors have become the major constraint to the overall performance of the ports service. By constructing anchorages, the congestion that happens frequently in harbor can be effectively eased, thus the traffic capacity is greatly enhanced. The purpose of this paper is to study the impact of anchorage number on waterway traffic capacity and provide theoretical foundation when deciding the anchorage scale. A simulation method with consideration of anchorages is adopted to analyze the vessels entering and departing process in coastal container terminal. Results show that waterway traffic capacity and anchorage number are polynomial correlated, waterway traffic capacity increases with the growth of anchorage number and ceases when beyond a certain level. It will be of great help to serve the planning and constructing ports and terminals.
Preparation of a New Fracture Ceramic Proppant
Authors: Tong Yu Ping , Wang Hui Xian , Wang Qing Feng
Published: October 2013

A new fracture ceramic proppant was prepared using the low-cost raw bauxite mineral as raw material, by adding the auxiliary material such as potash feldspar, manganese powder and nanocalcium carbonate. The obtained proppants were characterized by XRD and SEM. The crushing rate, particle size, sphericity and roundness of the products were satisfied the recommendation in the standard of the American Petroleum Institute APIR-60.
The Adsorption of Zinc(II) from Aqueous Solution on Modified Diatomite
Authors: Yang Zhong Zheng , Lu Yue Jun , Li Yang Yang
Published: October 2013

The removal of Zn (II) ions from aqueous solution was studied using raw diatomite and MnO2 modified diatomite samples at different adsorption parameters such as contact temperature, contact time, initial metal ions concentration and dosage of diatomite. The results showed that modified diatomite had a better adsorption than raw diatomite; adsorption increase with increase of time and then become almost stable, appropriate time is 15 min; adsorption increase with increase of dosage of Mn-ditomite, adsorption reached up to 95.7-97.2 % at 0.8-1.0g/mg dosage of Mn-diatomite to Zn (II) .
Study on Characteristics of Ultrasonic Velocity for the Concrete under Stress
Authors: Zhang Ling , Yan Chun Ling
Published: October 2013

Cube concrete (150×150×150mm) of five ages (7, 14, 21, 28 and 35 days) under different stress conducted the ultrasound examination by non-metallic detector and universal testing machine. The results show that the relationship curve of the stress and the ultrasonic velocity can be divided into three stages, the smooth straight stage, the linear deceleration stage and the attenuation destruction stage from the load beginning to the ultimate strength for the same age. There is a growing trend about the ultrasonic velocity with the increase of the age to concrete samples of C10 and C20 in the same loading; however, the overall growth trend of the velocity is not obvious to concrete samples of C30, C35, C40 and C45. It also shows that the relationship curve of strength level and the velocity can be divided into two distinct stages, the sharply increasing stage (C10-C30) and the fluctuating stage (C30-C45). Simultaneously, the paper further illustrates and explains the reasons to appear these stages and the phenomena.
Test Analysis of Shear Performance on Young-Old Concrete Interface between Bonded Rebar and Groove
Authors: Sun Hao , Liu Shi Lin , Li Xiao Gang
Published: October 2013

The young-old concrete can work together as a whole is the key issue of structural strengthening. Aiming at the technical selection problem appeared frequently in the bridge strengthening about the young-old concrete interface treatments between bonded rebar and grooving, 12 specimens were designed to compare with the shear performance and failure modes of the young-old concrete interface. The test results show that the failure characteristics of specimens which embedded steel bars are ductile, but the failure characteristics of specimens which slotted are brittle and the new concrete in slot position were cut off. And the young-old concrete interface shear strength of the specimens which embedded steel bars was distinctly stronger than that of the slotted specimens. So, the treatment of bonded rebar is proposed during the structural strengthening design. At the same time, the depth and distance of the bonded rebar should be well controlled.
Influence of Fiber Type on Behavior of High-Strength Concrete-Filled FRP Tubes under Concentric Compression
Authors: Vincent Thomas , Ozbakkaloglu Togay
Published: October 2013

This paper presents results from an experimental study on the behavior of circular high-strength concrete (HSC)-filled fiber reinforced polymer (FRP) tubes (HSCFFTs). Concrete-filled FRP tubes (CFFTs) have received significant research attention over the last two decades and experimental investigations into the axial behavior are abundant for normal-strength concretes (NSC) confined by either carbon FRP (CFRP) or class FRP (GFRP). However, the same cannot be said for CFFTs filled with HSC or manufactured with other fiber types such as aramid or high-modulus carbon FRP (AFRP and HMCFRP), where experimental testing is very limited. To address this research gap, this study examined the compressive behavior of 24 test specimens prepared with three different fiber types (CFRP, HMCFRP and AFRP) and manufactured with HSC. The experimentally recorded stress-strain relationships are presented graphically and the influence of fiber type and other key experimental outcomes are discussed. The results indicate that fiber type has a significant influence on the axial compressive behavior of HSCFFTs.
Effect of PVA Fiber on Mechanical Properties of High-Performance Concrete
Authors: Jin Zhe , Wang Cheng Ya
Published: October 2013

An experimental study has been conducted to investigate the effect of the fraction of PVA fiber on the mechanical properties of high-performance concrete. The mechanical properties include compressive strength, splitting tensile strength and compressive elastic modulus. On the basis of the experimental results of the specimens of six sets of mix proportions, the mechanism of PVA fiber acting on these mechanical properties has been analyzed in details. The results indicate that there is a tendency of increase in the compressive strength and splitting tensile strength when the fiber volume fraction is below 0.08%, and the compressive elastic modulus of high-performance concrete decreases gradually with the increasing volume fraction of PVA fiber with appropriate content.
Properties of MSFAC Long-Term Exposure to Sodium Sulfate Solution
Authors: Pan Li Yun , Liu Jian Dong , Li Lun , Li Xiao Ke
Published: October 2013

Experiments were conducted to study sulfate attack on concrete made machine-made sand and fly ash (MSFAC). The cubes with dimensions of 100 mm were cast and immersed in sodium solution with sulfate-ion concentration of 50000mg/L and tested after exposed for 30, 90, 180, 270, 360 and 540 days. The powder samples were made by steps of drilling, cutting and grinding. The sulfate-ion contents of concrete at different depths were measured by the chemical titration method. The results show that the sulfate-ion content of concrete decreased with depth, the sulfate-ion entered concrete by diffusion, permeation and capillary absorption. The sulfate-ion content of concrete decreased with the increasing replacement of cement by fly ash, and also decreased with the increase of exposure time when 30% of cement is replaced by fly ash. There are some advantages of using fly ash for concrete with machine-made sand to resist sulfate attack.
Crack Resistance and Permeability of Hybrid Fiber Reinforced Concrete Application in Understructure Work
Authors: Li Shu Jin , Qian Hong Ping
Published: October 2013

An investigation of early anti-cracking performance and permeability of hybrid cellulose fiber and PVA fiber reinforced concrete is presented in this article. The test results show that, both cellulose fiber and PVA fiber effectively improve the splitting tensile strength. The early anti-cracking performance of concrete is obviously improved by PVA and cellulose hybrid fibers, and there exists the synergistic effect for restrain matrix cracking with hybrid fibers. Based on the practical application of a subway station project during two years, result shows the underground concrete wallboard containing hybrid fibers does not produce obvious cracks and leakage problem.
Performances of Sandy Soil Stabilization with Fiber and Cement
Authors: Yuan Yu Qing , Guo Tao , Li Xue Chan , Li Wei
Published: October 2013

To study the influence of polypropylene fiber on the strength of sandy soil stabilization with cement in flooded area of Yellow River, a series of experiments 7-day unconfined compressive strength have been done when samples reach 7-day standard curing. Based on the data, it is found that fiber content has an important influence than its length on unconfined compressive strength. As for failure modes, there are significant differences between the samples of adding fibers and those adding nothing. After adding 10 % cement, 1 fiber with 12 mm single length, the unconfined compressive strength of sandy soil stabilization with cement can be greatly improved with increase rate of 83%. It is concluded that the sandy soil can be successfully stabilized by the combined action of fibers and cement.
Uniaxial Tensile Experiment on PVA Fiber Reinforced Cementitious Composites
Authors: Wang Hai Long , Peng Guang Yu , Luo Yue Jing , Sun Xiao Yan
Published: October 2013

Engineered cementitious composite (ECC) is a representative of the new generation of high performance fiber reinforced cementitious composites. To reveal the influence of mineral admixtures on the tensile mechanical characteristics of polyvinyl alcohol fiber reinforced engineered cementitious composites (PVA-ECC), the tensile properties of PVA-ECC with replacing cement by a significant amount of fly ash (FA), silica fume (SF) and metakaolin (MK) was experimentally investigated. Uniaxial tensile experiment was carried out using rectangular thin plate with sizes of 400×100×15mm3. Results from uniaxial tensile tests show that these mineral admixtures can improve the properties of PVA-ECC. The composite can achieve an ultimate strain of 2.0%, as well as an ultimate strength of 4.0MPa, with a moderate fiber volume fraction of 2.0%. In addition, the composites with FA, SF and MK show saturated multiple cracking characteristics with crack width at ultimate strain limited to below 175μm.
Mechanical Properties of a Green Hybrid Fibre-Reinforced Cementitious Composite
Authors: Tian He , Zhang Yi Xia
Published: October 2013

In this paper, a new green hybrid fibre-reinforced cementitious composite with high volume fly ash and steel and bagasse fibres is developed. High volume fly ash is used to partly replace cement and make the composite greener. Eco-friendly bagasse fibres from industrial waste and steel fibres are utilized to improve the mechanical behavior. In particularly, the influence of the parameters such as the sand/cement ratio and fly ash/cement ratio on the mechanical properties of the composite is investidated by evaluating the essential mechanical properties such as compressive strength and modulus of elasticity. The new green composite is found to be sustainable with high compressive. It is found that compressive strength of the composite decreases while the Young's modulus increases with the increase of the sand content, and that compressive strength and Youngs modulus of the composite decreases with the increase of the fly ash content.
The Mechanical Properties of Polypropylene Fiber Reinforced Polymer Modified Cement Mortar
Authors: Feng Huu , Gao Dan Ying , Yuan Jian Song
Published: October 2013

Combining the effect of polypropylene fibers, such as the decrease of cement base material shrinkage and plastic crack, and the increase of material toughness, with the improvement of polymer on the interface between the fiber and matrix, both polypropylene fibers and polymer modifier were used in the cement mortar at the same time to make more excellent cement mortar materials. The improvement for cement mortar from different length of polypropylene fiber, polymer modifier (waterborne epoxy emulsion), mineral powder and silica ash were studied. Results showed that compared with the short fiber, the long fiber has a more obvious effect on the toughness, the best dosage of which is 0.6 kg/m3; the waterborne epoxy emulsion improved the bonding properties of interface between polypropylene fiber and cement mortar matrix, and then, long fibers improved flexural strength of cement mortar greatly, in terms of short fiber, effect is not manifest; With the increase of mineral powder, all the mechanical index of polypropylene fiber reinforced polymer modified cement mortar were improved and the effect of silica ash was better than that of mineral powder, the optimal replacement ratio were 0.1 and 0.3 respectively.
A Review on Frost Resistance of Steel Fiber Reinforced Lightweight Aggregate Concrete
Authors: Li Xiao Ke , Song Wen Hui , Li Chang Yong
Published: October 2013

Compared with ordinay concrete, weight of lightweight aggregate concrete could be lower 20%-40% under same bearing capacity. Mixed with some given steel fibers in it, crack resistance and flexural strength will be improved. Once lightweight aggregate concrete mixed with steel fibers meets the requirements of frost resistance, it could be applied to most civil engineerings in a cold area. In this paper, the frost resistance mechanism of steel fiber reinforced lightweight aggregate concrete is introduced. The research status of frost resistance of steel fiber reinforced lightweight aggregate concrete is reviewed including the effects of water cement ratio, aggregate, mineral admixture and amount of fiber, frost resistance experimatal methods and engineering applications etc. Some further researches are prospected.
Study on Durability of Concrete with Machine-Made Sand Part I: Time-Dependent Chloride Penetration
Authors: Liu Chun Jie , Xu Yang Yang , Zhang Xiao Yan
Published: October 2013

As part of the studies on the durability of concrete with machine-made sand, this paper introduces the test results and the forecast model of time-dependent chloride penetration of this kind of concrete. Three strength grades of concrete C30, C40 and C50, and the contents of stone powder in machine-made sand of 5%, 9% and 13% in mass were considered in the mix proportion of concrete with machine-made sand. The ordinary concrete with natural river sand in the same strength grade was tested at the same time for comparison. The test was conducted for 360 days, the results showed that the effect of the content of stone powder on the chloride penetration of concrete was obvious at early curing time of 7 days, and tended to be lower with the increase of curing time. When the curing time was longer than 90 days, this effect could be neglected, and the resistance to chloride penetration of concrete with machine-made sand was almost equal to or larger than that of ordinary concrete. The decrement of chloride diffusion coefficient varied from sharp to gentle with the curing time, the resistance of concrete to chloride penetration increased with the increase of concrete strength. Meanwhile, to facilitate the calculation in practice, the forecast model of chloride diffusion coefficient of concrete is proposed.
An Investigation of Usability of Brown Coal Fly Ash for Building Materials
Authors: Gamage Nirdosha , Setunge Sujeeva , Liyanage Kasuni
Published: October 2013

The Victoria State of Australia has the second largest reserves of brown coal on earth, representing approximately 20% of the worlds reserves, and at current use, could supply Victoria with its energy for over 500 years. Its combustion, annually, yields up to 1.3 million tonnes of fly ash, which is largely use for land-fills. Disposal of fly ash in open dumps cause massive environmental problems such as ground water contamination that may create various health problems. This study focuses on the usability of brown coal fly ash to develop a sustainable building material. A series of laboratory investigations was conducted using brown coal fly ash combined with cement and aggregate to prepare cold pressed samples aiming to test their properties. Initial results indicate that compressive strength satisfies minimum standard compressive strength required for bricks or mortar.
Study on Losses of Self-Stress Created by Steel Fiber Reinforced Self-Stressing Concrete
Authors: Wang Bo Xin , Jin He Nan , Man Teng
Published: October 2013

Based on the 9-year-experiment of self-stressing concrete (SSC for short), the stability of self-stress caused by steel bars and steel fibers is investigated. The results show that the losses of self-stress are only from 0.6 MPa to 1.2 MPa during 2.5 years. Meanwhile the matrix of steel fiber reinforced self-stressing concrete (SFRSSC for short) has the characteristic of secondary expansion. Finally, according to the existing theoretical models, formulas of the losses of self-stress created by SFRSSC are obtained.
High-Strength Self-Compacting Concrete and its Application in Shenzhen Mangrove Garden
Authors: Xian Xiang Ping , Long Wu Jian , Chen Biao Yi , Huang Min Yi , Fan Yong Fa
Published: October 2013

Self-compacting concrete (SCC) refers to one kind of high-performance concrete which can fill formwork and condensed reinforced steel by the weight of concrete mixture without vibration. In this investigation, local raw materials from Shenzhen Jinqiang Concrete Co. Ltd were employed. Self-compacting concrete mixtures with targeted 3-day compressive strengths of 60MPa or 80MPa and required flow properties were evaluated. Moreover, the SCC was successfully applied in Shenzhen Mangrove Garden project.
The Analysis of Relationship between Stirrup and Longitudinal Reinforcement with Regression Analysis
Authors: Zhu Guo Liang
Published: October 2013

Regional confined concrete is a method which can strengthen constraint in the most needed position, it can make concrete, longitudinal reinforcement and transverse stirrup to form a more effective binding, and provide a stronger restraint in required regional giving full play the role of constraints. In the result analysis of the regional confined column specimen load test, we found that longitudinal reinforcement and stirrup strains have certain relationship. This article analyses the relationship between the two from the stirrup and longitudinal reinforcements strains in the contingency load, references are provided for the further development of regional confined concrete theory. Taking the two specimens as examples, the regression analysis was carried on between longitudinal reinforcement and stirrup strain, the relationship equation was obtained
The Influence of the Rib Depth on the Tensile Properties of GFRP Bar
Authors: Pang Yu Yang , Zhang Pu , Gao Dan Ying , Mo Fei , Yuan Jian Song
Published: October 2013

Different surface forms will have a huge impact on bond of GFRP rebar and concrete, and the ribs depth is the key factor that affects the bond with concrete, therefore, the surface forms and rib depth should be taken into account when GFRP bars are used as the structural reinforcement material. Based on two kinds of rib spacing and rib depth of GFRP reinforcement on tensile performance test, this article studies the different influence of ribs depth on the tensile properties and mechanism. Experimental results show that rib depth has distinctive impact for the GFRP tendons ultimate tensile strength, elastic modulus and ultimate elongation.
Experimental Method Study on Tensile Properties of GFRP Bar
Authors: Mo Fei , Zhang Pu , Gao Dan Ying , Pang Yu Yang , Zhao Ke
Published: October 2013

The GFRP bar has good mechanical properties and durability, but it is hard to test the tensile strength of large diameter FRP bar. Its test method given by ACI is too conservative, especially for large diameter FRP bar, and the length of test specimen will be too long and beyond the range of most testing machine. This article tested the tensile strength of GFRP bar using new methods, meanwhile, analyzed its stress distribution along the length of the specimens. The test results show that the use of bond anchor with steel plug or internal thread to measure the tensile strength of GFRP bar is feasible, and it can reduce the free length and the anchor length of the specimens, thus simplifying the test method of the tensile strength of FRP bars.