bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Fiber Gradation on the Edge Bearing Strength of Bamboo Culms
Authors: Sharma Bhavna , Harries Kent A.
Published: July 2012

Standardization, and thereby acceptance of any construction material requires years of testing and analysis. For structural bamboo, prototype model standards, in the form of the International Organization for Standardization (ISO) documents on bamboo design, testing and construction are available. While these provide useful guidelines, an important and often overlooked consideration in developing test methods is that these must be usable and reliably repeatable in the environment in which they are most expected likely to be used. The present work investigates the potential for adopting the relatively simple-to-conduct edge bearing test as an indirect means of obtaining the critical, although otherwise difficult-to-obtain transverse material properties. Expanding previous studies on transverse material properties, the research explores the effect of through-culm-wall fiber gradation on the edge bearing, or diametric compression, strength of full-culm bamboo. The test method utilizes a full culm section cut into two or three concentric annular sections. Tests results for each ring provide a measure of through thickness transverse properties. The objective of this work is the development of practical test methods for field assessment of bamboo material properties.
Study of EVA Blocks Waste Recyclability
Authors: Meira Flora Alexandre , da Paz Medeiros Fernandes Maria , de Melo Aluísio Braz , da Silva Elisângela Pereira
Published: July 2012

The use of EVA (Ethylene Vinyl Acetate) waste, from shoes industry, in the production of pre-molded block (EVA block) has been researched in the last 12 years. The results have shown great potential for these wastes to be used as lightweight aggregate, to replace natural aggregate in the manufacture of bricks made of cement based composites. This article examines the potentiality of waste EVA blocks recyclability, as aggregate in the production of new EVA blocks. In the experiment EVA blocks were molded in the mix proportion of 1:5 in volume (20% of sand and 80% of EVA) and determined the mass and compressive strength at 28 days. Then the EVA blocks were crushed and resulting aggregate was reused in part (portion retained on a 4.8 mm sieve) in the molding of new EVA blocks, using in dosages two different proportions of crushed aggregate (50% and 70%, EVAr - waste of crushed EVA blocks) in relation to the total volume of coarse aggregate of original EVA (EVA - waste from shoes industry). The average compressive strength at 28 days of the original EVA block was 1.2 MPa, whereas the block EVAr70was 2.2 MPa and the block EVAr50was 1.7 MPa. Thus, there was an 83% increase in the compressive strength on the block EVAr70and 44% on the block EVAr50. It was also noticed there was no significant difference among the weights of all the blocks produced. So, it appears that the EVAr aggregate impacted more in the compressive strength than in the mass of the blocks. Thus, the recyclability of the EVA block appears viable.
Fracture Toughness of Northeast China Larch
Authors: Qiu L.P. , Zhu En Chun , Zhou Hua Zhang , Liu L.Y.
Published: July 2012

Wood, as a green and environment-friendly building material, is widely used in building engineering. Naturally grown, wood has various defects like knots, cracks and inclined grain. Fracture Mechanics is thus an efficient tool to investigate the mechanical behavior of wood and wood-based composite products. According to Linear-elastic Fracture Mechanics (LEFM), fracture toughness can be introduced to measure the resistance to crack propagation. Crack was assumed to occur when the stress intensity factorKreached a critical valueKC.Fracture in wood usually involves not only the Mode I type (open) fracture, but also the Mode II type (shear) fracture. For getting a better understanding of the crack growth phenomenon of Northeast China Larch, it is, therefore, essential to assess theKICandKIIC, which are the critical stress intensity factors for Mode I and Mode II type fracture, respectively. In the current study,KICandKIIC, of Northeast China Larch were determined through tests with compact tension specimens and tests with compact symmetric shear specimens, respectively. In addition, the material properties tests were also performed. All of the specimens were cut from the same batch of Glulam beams. Based on the obtained data from experiments, LEFM was employed to explain the fracture failure in the form of crack propagation. Using Extended Finite Element Method (XFEM), simulation of the crack propagation in Mode I and Mode II was performed incorporating ABAQUS. The crack propagation and the load-displacement curves of numerical simulation were in good agreement with experiments, which validated that the proposed numerical approach is suitable for analysis of crack growth in the specimens. As part of a larger program to investigate the fracture behavior of Glulam beams made of Northeast China Larch, this study provides the material properties and validation of the numerical simulation approach. A series of experiments of full-size curved Glulam beams subject to bending and the corresponding simulations extending the numerical approach of this study to the cases of full-size wood composite members are under development.
The Effect of Knots on Bending Modulus of Elasticity of Dimension Lumber
Authors: Zhong Yong , Ren Hai Qing , Lou Wan Li , Li Xia Zhen
Published: July 2012

The defects, especially for knot, seriously affect the bending properties of wood. In this paper, full scale specimens and clear specimens for bending test, cut from dimension lumbers of Larix gmelinii with different kinds of knots, aimed to predictive accuracy of the modulus of elasticity (MOE) in bending and to improve the accuracy of MOE by multivariate regression analysis with density and knot information. According to the regression analysis results, the [(IK/Ig)·(MK/Mo)] of all knots and the average density ρa showed the best predictive accuracy of MOE for full scale specimen (Efull), with 0.674 of R2 and 1.15 of RMSE. Based on the ratio of regression parameter B/A of independent variables for density and knots information, the knots had less influential than density on influencing Efull. Finally, a simplified theoretical model that can be used to calculate MOE for dimension lumber, was defined as Efull/Eclear = B[(IK/Ig)·(MK/Mo)]+C .
Mechanical Grading of Structural Larch Dimension Lumber
Authors: Lou Wan Li , Ren Hai Qing , Wang Zhao Hui , Luo Xiu Qin
Published: July 2012

Larch dimension lumber bending strength properties from full-size bending test were used to establish preliminary grade boundary settings for mechanical grading of lumber by modulus of elasticity. Simulated production using the grade boundary settings were evaluated for modulus of rupture, ultimate tensile strength, and ultimate compressive strength. The results showed a good relationship between modulus of rupture and modulus of elasticity, and the observed relationships between strengths properties were consistent with that assumed for the standard grades. Through mechanical grading, larch dimension lumber could be sort grades: M14, M30 and M40. Assuming the visual requirements are met, the M30 and M40 grades account for more than 80% of the total production. Mechanical grading of larch appears to be a viable approach for grading Chinese large for structural applications.
The Effects of Thermal Loading on Masonry Structures
Authors: Gohnert Mitchell
Published: July 2012

Thin shell masonry structures are ideal for low-cost housing. Curved structures are ideally suited to resist external forces and are the most efficient structures. In shell structures, the forces are primarily in-plane, referred to as membrane forces. Shells, dominated by compressive stresses, are an absolute requirement in masonry structures, to minimize cracking. However, shell structures which are designed for pure compression still exhibit cracking on the external surface. Cracked shells are unsightly and a precursor to durability problems. For this reason, several studies have been undertaken to determine the cause of cracking in shells. This study is an investigation into the effects of thermal loading. The research includes the mapping of thermal loads by experimentation, an assessment of the effects of thermal loading and possible solutions to prevent cracking in the shell.
Effect of Timber Grain Orientation on Bonded-In Rod Connection Systems
Authors: Pearson Hannah , Evernden Mark , Harris Richard
Published: July 2012

Presented in this paper are the results of practical tests to determine some key material properties of engineered timber, in particular glulam. The results are discussed and compared with three known failure criterion, Hankinsons formula, The Tsai-Wu criterion and Maximum stress theory to determine if they are appropriate models for predicting the properties of glulam. The properties considered have been chosen with respect to a connection system for use in folded plate structures utilizing embedded rods. This paper considers the effect of the timber grain angle on the compression, tensile and steel dowel rod pull-out strengths. The test data shows that Hankinson and Tsai-Wu are both good models to predict both the compression and tensile behavior of engineered timber products at non-tangential angles, whereas maximum stress theory had less correlation and over predicts the results and would not be recommended for use in engineered timber materials.
Structural Behaviors of Chinese Historical Timber-Frame Buildings
Authors: Zhang Xi Cheng , Zhao Hong Tie , Sui Yan
Published: July 2012

As a kind of low-carbon, sustainable and environmental-friendly building material, wood has been widely used in ancient timber-frame buildings in China. Chinese ancient timber-structure buildings can not only provide a comfortable indoor environment, but also has an excellent structural behavior. Based on the study of horizontal and vertical layout of structural system, special constructional measures such as Cejiao and Shengqi, the structural behaviors of Chinese ancient timber-frame buildings were studied. Those conclusions were achieved: structural system layout in both horizontal and vertical comply with the existing anti-seismic conceptual design thoughts. When subjected to earthquake, the seismic actions are reduced by means of base sliding isolation, energy dissipation and shock absorption of mortise-tenon joints and tou-kung sets, which make Chinese ancient timber building a multiple aseismic system. Cejiao and Shengqi are equivalent to passive control in modern buildings, which improve the structural integrity, stability and aseismic capacity greatly. The post-and-lintel roof truss is a good way of saving material.
Study on Wooden Shan-Jia Structural of the Tile Board House Residence of Yi Minority in Liangshan
Authors: Song Shang Nan , Li Zong Zhan , Cheng Bin
Published: July 2012

The wooden shan-jia structure (The braced arch structure), the main load-bearing structure in the traditional tile board room of Yi minority, is one of the residential elements which are most distinctive and most valuable to be protected. As the traditional architectural culture of the Yi, the structure is still being widely used in local residence, but the Liangshan Yi Minority is located in high intensity earthquake zone, which cause large security risks on the wooden frame system. In this paper, three kinds of common and typical layouts of braced arch structure are collected after investigating of the wooden shan-jia structure. The structural weaknesses are found through the simulation of ANSYS. Finally, propose some measures to optimize the structural design, in order to enhance the seismic optimization and improve the construction technology of tile board room.
Non-Traditional Materials, Technology and Non-Traditional Research Mode
Authors: Ye Qiang , Ju Tuo Wen , Chen Na
Published: July 2012

In order to obtain better social and economic benefits, non-traditional materials and technologies must be closely integrated with non-traditional research mode. Traditional studies on materials and techniques are mainly undertaken by engineers of structures and materials, while architects play the role in the application of materials and technologies. Therefore, the application of new materials and technologies shall be inevitably accepted, well acquainted with and proficiently utilized by architects. The three factors that have a major impact on this process are the complexity, differentiation and timeliness, indicating that the application of new materials and technologies is simpler, similar to the application method of traditional materials and technologies and can be learned and mastered by architects in a short time. The hardcore of non-traditional research mode is the close coordination between architects and the engineers of structure and materials, the design methods and technical details that adapt to new materials and technologies.
Micro-Silica for High-End Application from Carbon Capture and Storage by Mineralisation
Authors: Sanna Aimaro , Dri Marco , Wang Xiao Long , Hall Matthew R. , Maroto-Valer Mercedes
Published: July 2012

Waste silica remaining after the Carbon Capture and Storage by Mineral carbonation (CCSM) could represent a potential pozzolan material for partial replacement in concrete. The objective of this work was the production and testing of cement gel cubes with the residual-silica by-product obtained from the accelerated carbonation of Mg-silicate rocks. The silica produced was characterised in terms of its chemical composition, morphology and LOI. Also, the silica was used as an additive to the cement (CEM I class) in order to assess the effect on (28 days) compressive strength in comparison with a cement control specimen. The influence of different cement replacement percentages (5% and 10wt.% silica) were determined by measuring initial setting times and compressive strength. The compressive strength of the cement specimens with 5 and 10wt.% silica as pozzolan replacement of Portland cement were 3% and 8% higher than the control cubes indicating that the residual silica powder may have pozzolanic properties. However, high LOI and magnesium content might represent a limit in high-end applications and further work is required to identify optimised CCSM conditions able to reduce the impurities in the silica by-product and to establish their potential as a pozzolan.
Inter-Story Capacity Spectrum for the Performance Based Seismic Design of Vertically Irregular RC Frame Structures I: Method
Authors: Men Jin Jie , Shi Qing Xuan , Zhou Qi
Published: July 2012

Considering the dynamical characteristic of structure under different earthquake hazard level, inelastic demand curves, namely, inter-story shear versus inter-story displacement curve are established by using mode spectrum method. Based on the relation of structure performance object and displacement ductibility, the relation of structure performance object and inter-story demand curve is established. And the inter-story demand curves take into account the inelastic behavior of structure under earthquake action adequately. Then considering the seismic respond characteristic and the capacity curve of the frame structure a new method named inter-story capacity spectrum (ISCS) is put forward for the performance based seismic design of vertically irregular frame structures. Examples are presented to demonstrate the applicability and utility of the proposed method. In part , the procedure to establish the ISCS method is mainly explained. And the examples will be introduced in part .
Green Chemistry for the Production of Biodegradable Polymers as Solid Substrate and the Formation of Sustainable Biofilm
Authors: Tiwari Archana , Ramirez Alejandro Manzano , Jain Roopesh , Saxena Anushri
Published: July 2012

Conventional plastics derived from the fossil fuels pose a threat to the global environment due to their non-degradable nature. Problems associated with global warming and solid waste management has generated interest in the development of novel plastics. Theses while retaining the desired properties of conventional synthetic plastics must also are degradable. Among the various biodegradable plastic available, there is growing interest in the group of polymers known as polyhydroxyalkanoate (PHA).The present investigation is based on (i) Biodegradation of Bioplastic with biological approaches (ii) Production of cost effective Bioplastic. Cost of bioplastics serves as a hindrance to the development of bioplastics for food and drink packaging as the plastic is produced by harvesting the natural resources thus there is utilization of the agricultural waste and also reduces the overall cost of the product. As in the case of petroleum based plastic production, there is the need of huge sum of energy which consumes the non renewable sources which is getting depleted. Thus, we can conclude that having a cost effective bioplastic in our near future. This plastic will be replacing the commercially available plastic very soon. The bioplastic produced is also degradable. It thus reduces the waste accumulation on the areas surrounding us. It is also suggested that on degradation it does not produces any toxic to the environment and no harmful gas is emitted thus no greenhouse gas and no global warming. This would be an environment friendly product.
Experimental Determination of Allowable Stresses for Bamboo Guadua Angustifolia Kunth Structures
Authors: Luna Patricia , Lozano Jorge , Takeuchi Caori Patricia , Gutierrez Mateo
Published: July 2012

The earthquake on 1999 in Armenia city (Colombia) showed the good seismic performance of structures using bamboo guadua as main material but also the mistakes caused by improper techniques of construction and the lack of parameters design for this type of structures. This work presents the experimental methodology used for the determination of allowable stresses for the design of bamboo guadua structures, used in the project "Validation of Guadua Angustifolia as a structural material for design, by the allowable stresses methodology" financed by the Ministry of Agriculture and Rural development of Colombia (Ministerio de Agricultura y Desarrollo Rural de Colombia) and developed by National University of Colombia (Universidad Nacional de Colombia) since the year 2008 when there were no allowable stress design standards for this structures in Colombia. For the determination of the allowable stresses were carried out tests of samples in compression, tension, and shear parallel to the fiber, compression perpendicular of the fiber and bending beams with bamboo guadua from three different areas of Colombia. It was found also the flexural elastic modulus for the material.
Application and Research Progress of Aluminum Alloy Bridge Decks
Authors: Zhang Yang , Qiu Jun Feng , Bai Hei
Published: July 2012

In order to increase live-load carrying capacity and life of bridges, aluminum alloy bridge decks have been widely used in bridge structures for more than 70 years because of the features of high strength-to-weight ratio, excellent corrosion resistance, ease of fabrication and recovery, rapid construction, maintenance-free and cost effective. First, this paper provides in detail the advantages of aluminum alloy bridge decks and the main areas of aluminum alloy applications in bridges can also be pointed out. Then, a brief overview of typical application examples and structural shapes of aluminum alloy bridge decks are introduced. At the same time, a state-of-the-art review on the researches of aluminum alloy bridge decks, related to static behaviors, fatigue properties, dynamic responses, structural systems and cost effective, is presented. Finally, the perspectives of research and development on aluminum alloy bridge decks are discussed.
Studies on a Low Concentration Photovoltaic/Thermal System with Constant Volume Refrigeration
Authors: Xu Yin , Wang Cheng Yao , Hua Yong Ming , Zhang Yao Ming
Published: July 2012

To conserve operation energy consumption and improve outflow availability, a novel low concentration photovoltaic/thermal system with constant volume refrigeration was proposed in this paper. The outdoor experiment, carried out in Nanjing, suggested that the thermal efficiency could approach to 39.4%, while the electrical efficiency could reach 14.1% with 40 outflow. Applying the implicit finite-volume method, a model of this system was also derived. Based on the measured environment data, the performance of this system was simulated and validated by the experiment data.
Research on Optimization for Reinforcement of Structures
Authors: Hu Jun , Yang Zhi Yong , Zhao Song , Liu Shun Hui
Published: July 2012

The choice of structural reinforcement, such as increasing cross-section, steel-bonded, carbon fiber reinforced and etc, is affected by many factors. How to create optimal model is a major unresolved issues for designers to decide more scientific and rational structural reinforcement. The research obtains the weight of factors by Analytic Hierarchy Process and ascertains relative membership degree of factors by theory of Fuzzy Mathematics, and transforms qualitative impact of these factors into quantitative analysis, then the optimizing model is set up by The Generalized Hamming Distance as p=1 which is analyzed by an actual engineering that we can certificate the model valuable and useful. The research provides a simple and intuitive method of quantitative analysis for reinforcement by establishing optimization model, especially for both multi-objective and multi-factor decision-making, and overcome the arbitrariness when determining the reinforcement.
Preliminary Research on Characteristics of Bamboo Briquette Charcoal as Solid Fuel
Authors: Wang Lu , Guan Ming Jie , Zhang Qi Sheng
Published: July 2012

t is particularly important to develop biomass briquette as alternative solid fuel for the decline of natural coal reserves. This paper focused on analysis of preliminary characteristics of briquette charcoal made from bamboo processing residues. We conducted proximate analysis including content of volatiles, fixed carbon, moisture and ash respectively; determined its density, durability and combustion characteristics. Those results will provide significantly technical parameters for utilization of bamboo waste and biomass resources as solid fuel.
Analysis of Parameters' Sensitiveness of Long-Span Hybrid Girder Cable-Stayed Bridge
Authors: Li Zhong San , Lei Jun Qing , Yan Dong Huang
Published: July 2012

In order to improve the construction control precision of long-span hybrid girder cable-stayed bridge, the design parameters such as the weight of girder, the cable tensile force and the stiffness of cable are conducted sensitivity analysis through computing and comparing the influences of these parameters on the deflection of girders, the stress of girders and the cable force in the bridge's completion state. It was shown by the computation results that the main parameters of long-span hybrid girder cable-stayed bridge are the weight of girder and the cable tensile force, the stiffness of cable has a little influence on the completion state of the bridge. With this approach, through modifying the main parameters, while ignoring the influences of the secondary ones, the Jingyue Yangtze River Highway Bridge construction control has been successfully done. The test results show that the cable force and the contour of the bridge are in good state. They are both in the range of control, the relative error of the cable force is less than 3% and the elevation deviation is less than 5mm.
AE Identification of Flanged Connection Condition in Vibration Environment
Authors: Wang Ning , Yao Yong , Tao Jun Lin , Long Lin
Published: July 2012

On the basis of vibration testing of flanged connection structure, AE signals gathered are carried on processing with MATLAB,mainly the reconstructed signals. The concepts of characteristic frequency band and the superiority frequency band are drawn, and the layers of wavelet packet decomposition are determined, and the frequency band distributed characteristics of acoustic emission (AE) are obtained. With the percentage of wavelet packet energy band, the strengths of superiority frequency band and the relationship of torque and it are gotten quantitatively and it is found that the energy has certain regularity with the torque changing, and proposed that express its rule characteristic with wavelet packet energy spectrum rate of change this target in order to achieve the identification of the connection structure condition.
Flexural Behavior of Innovative Hybrid GFRP-Reinforced Concrete Beams
Authors: Li Xian , Lv Heng Lin , Zhou Shu Chun
Published: July 2012

Fiber-reinforced polymer (FRP) bars are emerging as a competitive option for replacing steel bars as reinforcement in various concrete structures exposed to aggressive environments. However, the low elastic modulus and brittleness of FRP bars significantly reduce the stiffness and the ductility of FRP-reinforced concrete (FRP-RC) members. In order to improve the flexural behavior of FRP-RC members and meanwhile ensure their satisfactory corrosion-resistant performance, an innovative FRP-reinforced concrete encased steel composite (FRP-RCS) member, which consists of ductile structural steel shapes in combination with corrosion-resistant FRP-reinforced concrete, was conceived and studied. An experimental investigation on the flexural behavior of the proposed FRP-RCS beams was conducted by testing a total of five large-scale simply supported beam specimens subjected to four-point bending loads. The test specimens included one FRP-RC beam reinforced with GFRP bars only and four FRP-RCS beams reinforced with both GFRP bars and encased structural steel shapes. The main parameters considered in this study were concrete compressive strength and amounts of GFRP reinforcement. The test results indicated that using encased steel shapes provided a significant enhancement in load carrying capacity, stiffness, ductility and energy absorption capacity of test beams. The tested FRP-RC beam suffered a brittle failure caused by sudden fracture of tensile GFRP bars whereas the proposed FRP-RCS beams behaved in a ductile manner due to the beneficial residual strength of encased steel shapes following concrete crushing. In addition, the experimental results also demonstrated that the concrete compressive strength had little effect on load carrying capacity of FRP-RCS beams whereas the load carrying capacity can be enhanced by increasing the reinforcement ratio. Analytical methods were also constructed using OpenSEES2.2.2 to simulate the load-deflection response of tested beams..
The Quota and Analysis of Comprehensive Energy Consumption per Unit for Residential Buildings in Changsha
Authors: Huang Qing , Li Nian Ping , Wei Xiao Qing , Jiang Yun Sheng
Published: July 2012

Using an appropriate evaluation index for energy consumption is advantageous for evaluating energy saving effect of buildings correctly and carrying out energy-saving action reasonably. As a result, it is important to establish a practical quota of energy consumption for promoting energy-saving emission reduction. Energy consumption for residential buildings has been influenced by the behavior of residents in the building largely, and has a higher uncertainty, so it brings great difficulty to researches. Considering the characteristics of residential buildings, this paper uses comprehensive energy consumption per unit as evaluation index. Based on the investigation results and related studies, the residential buildings in Changsha are analyzed with statistical methods, in order to know more about the energy consumption level and structure for the residential buildings in Changsha. This paper shows the characteristics of the energy consumption of the residential buildings in Changsha, and work out the range of the comprehensive energy consumption per unit. The result provides a reference to make out energy policy and enhance the management of energysaving. It can be also used to guide the residents have a reasonable electric power utilization.
Adaptability Analysis of New Ceiling Radiant Cooling Panels with Dedicated Outdoor Air Systems Used in Summer Moist Heat Regions
Authors: Zhang Xu Han , Li Nian Ping , Yang Jian Guang
Published: July 2012

This paper introduces the operating principle and system components of Ceiling Radiant Cooling Panels (CRCP) with Dedicated Outdoor Air Systems (DOAS), moreover, analyses not only the advantages of CRCP/DOAS system in terms of comfort, energy conservation and healthy environmental protection, but also the three obstacles to the system when running in summer moist heat regions condensation, radiant cooling capacity and first cost. The major defect of CRCP is proposed that the surface temperature of the panel is uneven, while the shortage of DOAS is the insufficiency of outdoor air handling. A new CRCP/DOAS system is provided in this paper, including patent radiant cooling panel and patent air condition. We also expound the characteristics of this new system, and list the recommended design parameters as well.
Selected Physical and Mechanical Properties of Bamboo and Poplar Composite OSB with Different Hybrid Ratios
Authors: Yong Cheng , Guan Ming Jie , Zhang Qi Sheng
Published: July 2012

Bamboo has been known as a good substitute of engineered wood raw material in the world for its naturally oriented high strength. In this paper, we made the bamboo and poplar composite OSB (oriented strand board) with different hybrid ratios in order to understand the technical feasibility of this composite OSB and to expand the engineered utilization of bamboo. The physical and mechanical properties are tested and the effect of different hybrid ratios on physical and mechanical properties of the board was analyzed. Using this bamboo and wood mixed structure, not only are we to improve the properties of the board, but also to expand the application fields, moreover to enhance the utilization ratio of resources.
Design and Use of the Joint between Concrete-Filled Square Steel Tubular Special-Shaped Columns and Steel Beams
Authors: Chen Xi
Published: July 2012

Environmentally sustainable building construction has experienced significant growth during the past 10 years. The public is becoming more aware of the benefits of green construction, and green building is leading to changes in the way of owners, designers, contractors, and approach of the design, construction. Concrete-filled square steel tubular special shaped columns - steel beams residence installing efficient and light heat insulation wall is welcome for both owners and designers because of the columns having the same thickness with limb-filled walls, no-shocked indoor, easy to decoration and furniture layout, increasing in the actual using areas and saving carbon. The composite frame fully develops the merits of steel and concrete, and thus is reasonable and economical from both structural and construction viewpoints. The connection region as main force transfer component is key to the research of frame. Compared with the joint of ordinary reinforced concrete special shaped frame, the joint between concrete-filled square steel tubular special-shaped columns and steel beams has the advantage of better ductility , higher loading capacity, uncomplicated reinforcement disposing and convenient in construction. This paper discusses the features of concrete-filled square steel tubular special shaped columns - steel beams frame, and the design and use of beam-column joint. From the experimental study on seismic behavior of the joint, it is shown that the joint has strong energy dissipation capacity and higher loading capacity. So it is expected it could play an important role in residence structures. This study is helpful for further study of the design and use of the joint between concrete-filled square steel tubular special-shaped columns and steel beams.
Research on Compound Condensation/Evaporation of Four Functional Heat Pump Performance
Authors: Zhang Xiao Heng , Gong Guang Cai , Zhou Jian Yong
Published: July 2012

Compound condensing heat pump combines the advantages of heat pump technology and condensing heat recovery technology. It takes full account of the common infrastructure in the cooling and heat source system and greatly increases equipment utilization ratio. It also recycles condensing heat to produce sanitary hot water efficiently while ensuring cooling and heating of heat pump to achieve the same effect. The distinctive technical features of the compound condensation / evaporation of four functional heat pump ensure its efficient and reliable operation. This heat pump system runs in several models throughout the year,which include the refrigeration mode, refrigeration&domestic hot water mode, domestic hot water mode and heating mode. The performance in refrigeration mode and refrigeration&domestic hot water mode is studied by a designed experiment is done and the an explicit analysis is made. By comparing the results of simlation and experiment,an agreement can be shown clearly. Therefore,the final conclusion is drawn:the performance of compound condensation / evaporation of four functional heat pump is improved over the traditional heat pump.It is worthy to further promote for the sake of energy saving.
Flexural Behavior of NSM CFRP - Stone Composite Beams: Experimental Investigation
Authors: Guo Zi Xiong , Ye Yong , Liu Bao Cheng , Liu Yang
Published: July 2012

A technique for increasing the flexural behavior of stone beams using near-surface mounted (NSM) carbon fiber reinforced polymer (CFRP) rods is proposed. Four granite beams were tested under monotonic loading to investigate the effectiveness of this technique. One conventional stone beam was kept unreinforced as the control specimen and three beams were reinforced with NSM CFRP rods. The main test parameters included rod diameters and reinforcement ratios. Three types of failure modes were observed during testing, namely, abrupt fracture for conventional stone beams, flexure failure for moderately-reinforced beams and flexure-shear failure for over-reinforced beams, respectively. Test results showed that reinforcing with NSM CFRP could significantly enhance the flexural behavior of stone beams. For specimens with a reinforcement ratio of 0.14%, an average increase up to 91.0% in the ultimate load with respect to that of the control beam was obtained and the deformation capacity was dramatically increased. For specimens with a reinforcement ratio of 0.28%, though flexural behavior was greatly enhanced, an unfavorable shear failure was observed.
Research of Thermal and Moisture Transport within Compound Bamboo Wall with Different Moisture Content
Authors: Xiang Lin Lin , Li Nian Ping , Chen Zhou , Chen Xue Wen
Published: July 2012

In order to evaluate the energy-saving effect of the bamboo plywood as building enclosure, by measuring thermal conductivity of compound bamboo building enclosure with different moisture content, performance function between bamboo characteristic and thermal conductivity were deduced with numerical analysis method. First, we measured thermal conductivity with different moisture content. For the accuracy of data, we put a thin plastic film between the heating layer of the tester and the bamboo plywood to reduce water evaporation. Then we got the functional relation of moisture content and thermal conductivity, by using numerical analysis software. Finally, according to the national related standard and the performance of the bamboo plywood within different moisture content, we analyzed the advantages and disadvantages of the bamboo plywood as building enclosure. The results showed that the heat preservation and thermal insulation properties of bamboo plywood as construction materials are both stronger than traditional building materials such as reinforced concrete with different moisture content. Meanwhile, so as to ensure the heat preservation and thermal insulation properties and to achieve a good energy saving effect, wed better keep the moisture content of bamboo plywood in a low state.
The Effects of Opening Windows Behavior on Indoor Air Quality of a Newly Decorated Office Building
Authors: Shen Xiao Hang , Li Nian Ping , Fan Xiao Jia , Wu Yan Lin , Ke Yu Zeng
Published: July 2012

In the newly decorated office premises, the architectural decoration material will release much polluted gas, thus the IAQ is highly concerned. Natural ventilation through open windows can influence the IAQ. To study the effects of opening windows on the indoor air quality of newly decorated office premises, we choose several newly decorated offices in a commercial building in Changsha, a city in hot summer and cold winter region of China, as the study object. The 4 contrastive research schemes in the winter are adopted to acquire the results. Field-testing and air sampling methods were taken respectively to the 4 schemes to measure the concentrations of the main pollution composition such as formaldehyde, ammonia, benzene and TVOC in the offices. Meanwhile, relevant questionnaire surveys towards the four schemes were taken to the staff in the offices. We have synthesized and analyzed the IAQ condition of the 4 research schemes from the results of the tests and surveys. The result of the study shows that: the IAQ is the worst and cannot come up to the national standard when closing windows all day long in the newly decorated offices. Also some staff have a series of adverse reactions working in the work environment for a long time. All the other three schemes can improve the IAQ differently, and the scheme that opening windows all day long can improve the IAQ the best. Meanwhile, people can feel the change of IAQ effected by the 3 ventilation schemes if he/she is working for a long time in the offices.
Study on the Deterioration Process of Cast-in-Place Hinged Joints in Hollow Slab Bridge under Deicing Salt Environment
Authors: Wei Jun , Li Pei , Ban Xia , Dong Rong Zhen
Published: July 2012

Fabricated hollow slab bridge is commonly used in China. It is indicated that the hinged joints between hollow slabs are easily damaged. Especially under the erosion of chloride salt, the destruction process of hinged joints will be greatly exacerbated. In this paper, deicing salt environment was simulated in the lab to corrode the commonly used hinged joints. According to static load test results, hollow slab coordinated working coefficient is explored and the regression calculation formula was established. Then, the time-varying function of the rate of hinged joint steel corrosion was introduced to the regression model. Finally, the constantly evaluating of the hinged joint durability performance of common used deep, middle and low hinged joint forms were also carried out.
Application Research on the New GFRP Members Based Modified Behavior Used in Building
Authors: Huang Jing , Wei Zhuo Bin , Gao Yi
Published: July 2012

Glass fiber reinforced plastics (GFRP) is an immensely versatile material which combines lightweight with inherent strength. For the properties of sustainability, energy efficiency and reduction of CO2 of GFRP, they can be used in green building as a kind of the energy-efficient and environment-friendly material instead of the conventional materials. Based on the less elastic modulus and lower wave-transparent properties of glass fiber reinforced plastics for unsaturated polyester resin (UPR-FRP), a new kind of glass fiber reinforced plastics based modified unsaturated polyester (MUPR-FRP) was put forward. This paper presents material behavior and technical process of the new MUPR-FRP. For the modified property, the MUPR-FRP members may have the well superiority compare with the steel and the concrete materials used in strengthening engineering and special loading resistance.
Finite Element Analysis and Bearing Capacity Research of the New GFRP Strengthening Frame Members Based Modified Behavior
Authors: Gao Yi , Wei Zhuo Bin , Huang Jing
Published: July 2012

Based on the research of the new kind of glass fiber reinforced plastics based modified unsaturated polyester (MUPR-FRP). This paper presents the result of the numerical evaluation of bearing behavior of the MUPR-FRP strengthening frame members. The MUPR-FRP strengthening members were modeled using the nonlinear finite element software ANSYS and the load deflection behavior and ultimate capacity were evaluated numerically. For the FE model, members were modeled using Tsai-Wu with tension cut-off failure criterion. The numerical results and the bearing capacity research indicated that the stress of new MUPR-FRP strengthening frame members was less than the load bearing strength and the deformation could satisfy some requirements in use.
Experimental Research on Interfacial Bond Performance in Rock Anchor with High-Performance Grouting Medium
Authors: Fang Zhi , Zhang Hong Qiao
Published: July 2012

There exist the problems such as low bond strength and bad durability in the ordinary grouting slurry of the ground anchor system at present. The high-performance grouting mediums RPC (Reactive Powder Concrete) and DSP (Densified Systems containing homogeneously arranged ultrafine Particles) would become the potential replacement of grouting medium in ground anchor resulting from their high compressive strength, durability and toughness. Based on a series of pull-out tests on ground anchors with different high-performance grouting medium of RPC and DSP , different bond length in the construction field, the bond performance on the interfaces between anchor bolt (deformed steel bar) and grouted medium as well as between grouted medium and rock mass was studied. The results indicate that the interfacial bond strength between RPC or DSP and deformed steel bolt ranges within 23-31Mpa, far greater than that (about 2-3MPa) between the ordinary cementitious grout and deformed steel bar. Even though the interfacial bond strength between the grouted medium and rock mass of limestone was not obtained in the test since the failure mode was pull-out of those steel bar rather than the interface shear failure between grouted medium and rock mass, the bond stress on the interface reached 6.2-8.38 MPa, also far greater than the bond strength (about 0.1-3MPa) between the ordinary cementitious slurry and rocks.
Using Artificial Intelligence to Build with Unprocessed Rock
Authors: Lambert Malcolm , Kennedy Paul
Published: July 2012

Unprocessed rock is a massive resource of very cheap building material with very low embodied energy. However, it is highly underutilised due to the difficulty of dealing with irregular shaped blocks. We have developed a novel software application using the artificial intelligence methods of search and optimisation to simulate building three-dimensional structures in a virtual world. The aim of our software is to help builders solve the 3-dimensional jigsaw puzzle of building with rock rubble with an emphasis on its potential use for building sustainable housing and infrastructure. This paper describes our approach and the design of our software including an overview of the rock digitising, optimisation software and building methods. We present simulation results of building and testing several small drystone structures using the prototype software.
High-Performance Grouts for Rock Anchor
Authors: Fang Zhi , He Shao Hua
Published: July 2012

The mix proportion of DSP for the sake of rock anchor grouting has been studied, and the effects of water-binder ratio, volume of nanometer silica added in and various curing methods on the behaviour of the grout have been investigated. Based on the test results, a appropriate proportion of DSP grout with good working and mechanical performance was successfully found.
Introduction of Tilt-Up Construction and Details of Connection
Authors: Han Qing , Wang Yi Hang , Zhang Guo Wei , Wu Hui
Published: July 2012

Tilt-up is a method for constructing concrete wall rapidly and economically without formwork. A large number of tilt-up structures have been constructed in North America and other developed countries, and it will also be an acceptable term for new construction in China. Tilt-up process can reduce the cost of labor and materials in wall construction. As the damage of earthquake, the connection of the tilt-up building is the most important part which attracts more attention to engineers. At the end of this paper, details of connection are discussed as the codes introduced.
The Flexural Characteristics of Prestressed Bamboo Slivers Reinforced Parallel Strand Lumber (PSL)
Authors: Cui Hai Xing , Guan Ming Jie , Zhu Yi Xin , Zhang Zhen Zhen
Published: July 2012

A novel kind of parallel strand lumber (PSL) was produced, in which bamboo slivers with viscoelastic deformation were mixed with poplar veneer strands at a weight ratio of 1:4 as raw materials, then the flexural characteristics of PSL were investigated. The results showed that stretching treatment was an effective method to generate viscoelastic deformation of bamboo slivers, which would induce prestress in the bamboo slivers, reinforced PSL. The modulus of rupture (MOR) and modulus of elasticity (MOE) of prestressed bamboo slivers reinforced PSL were 7.84% and 11.76% higher than that of control PSL respectively. The flexural toughness index of prestressed bamboo slivers reinforced PSL was increased by 27.55% compared with control PSL. The presence of prestress in bamboo slivers reinforced PSL significantly enhanced its flexural stiffness and toughness, while it had no obvious effect on its flexural strength.
Effect of Load Shape in Cyclic Load Variation on Dynamic Behavior of Spur Gear System
Authors: Chaari Fakher , Bartelmus Walter , Zimroz Radoslaw , Fakhfakh Taher , Haddar Mohamed
Published: July 2012

Transmissions including spur gears are widely used in several industrial applications. They are characterized by high efficiency and capability to transmit high torques. A special attention should be made for transmissions running under varying loading conditions which have to be well monitored. The presence of this variability associated with defects that may occur in the transmission will complicate its condition monitoring. The first step to overcome this difficulty is to identify and characterize the dynamic response of the transmission in healthy conditions subjected to variable loading conditions. In this paper, a model based approach is presented in order investigate the influence of the loading shape on the vibration characteristics of the transmission. A dynamic model of a one stage spur gear transmission including a time varying loading conditions is developed. Two cases of loading conditions are considered. A parametric study is achieved and main conclusions are discussed.
Electromechanical Impedance Based SHM System for Aviation Applications
Authors: Rosiek Mateusz , Martowicz Adam , Uhl Tadeusz
Published: July 2012

This paper concerns an approach based on the electromechanical impedance for damage detection and monitoring of aircraft components. In the introductory part of the paper the theory of proposed method and the characteristics of elaborated structural health monitoring system are briefly described. Afterwards, applications of described system applied to damage detection in different aircraft components are presented. First, the process of monitoring of bolted joints localized in the fuselage is described and effectiveness of this process is discussed. In the application four PZT patches were used to track a torque decrease in three joints. The latter application deals with monitoring of riveted engine housing made of aluminium. Introduced notch was monitored with two MFC transducers. In both mentioned cases the frequency characteristics of measured impedance were compared using different deterministic and statistical damage indexes.