bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Design and Control of Dual-Energy Source System for Pure Electric Vehicle
Authors: Min Wei
Published: May 2020

Based on the analysis of the structure of dual-energy source storage system and the requirements of drive motor for the power of the battery and super capacitor under different operating conditions, and according to the motor’s required power and the battery and super capacitor’s SOC (State of Charge) and other parameters, a corresponding distribution fuzzy control strategy of dual-energy source power is established. A complete electric vehicle model of a dual-energy source pure electric vehicle driven by a DC (Direct Current) motor is constructed by Matlab. The system simulation results show that the battery-super capacitor dual-energy source system can simultaneously meet the dual requirements of energy and power of the pure electric vehicle. Both the economy and power have been improved. Compared with the single-battery power supply of pure electric vehicles, the electric motor drive system of pure electric vehicles with dual-energy sources is more efficient. And the mileage for a single continuous charge, the maximum speed, the shortest acceleration time of 50 km/h and maximum gradeability of 50km/h are improved. The mileage increases by 32.4%. At the same time, the charge and discharge current and temperature of the battery are significantly reduced, and the service life of the battery is effectively.
Symmetry detection algorithm to detect forwarded spoofing interference signals of BOC modulation receivers
Authors: Wang Zhiying , Liu Yucen , Wang Menglan
Published: May 2020

In this paper, the symmetry detection algorithm based on the symmetry of binary offset carrier (BOC) modulation signals is proposed to solve the problem of the global navigation satellite system (GNSS) spoofing interference in BOC modulation and acquisition phase which set on the base of the characters of correlation peaks, and achieve the detection of the forwarded spoofing interference signals. The theoretical value and the simulation value of the receiver operating characteristic (ROC) curve of the symmetry detection algorithm can be obtained by the numerical calculation and the experimental simulation. It can be seen from the simulation that with the increase of the accumulation times after the correlation, the signal to noise ratio (SNR) of the spoofing signal compared to the real signal, and the SNR of the real signal, the detection probability of the spoofing signal increases as well. When the power of the spoofing signal is 3 dB greater than that of the real signal, the detection probability can be more than 99% under the condition that the false alarm probability is 0.1%. Given that it only needs to add the module to the software receiver to detect spoofing signals, the algorithm proposed in this paper is of practical significance.
The effect of silica fume inclusion on the properties of recycled concrete aggregate- containing concrete
Authors: Akpinar P , Al Attar H M E
Published: May 2020

Protecting the environment against the hazards of construction and demolishing (C&D) wastes is crucial. Elimination of C&D wastes by using them as recycled concrete aggregates (RCA) within the manufacture of new concretes is a promising solution for this problem. Since RCA coming from demolished structures have poor qualities, overall performance of new concrete should be monitored carefully. Without achieving a satisfactory strength performance, manufacturing concretes with RCA could not be widely accepted in construction sector. This study investigates the effects of silica fume, which is an effective pozzolanic material, on the properties of concrete mixtures made with 50%RCA as a replacement to quarried aggregates. RCA used was obtained from a 25-years old public building in Nicosia that was structurally failed and demolished. Results obtained indicated a 12.3% water demand increase for obtaining the targeted slump when SF was added in fresh concrete. The increase in compressive strength of concrete with SF in 28 days was 1.5%, where this increase was recorded as 8.1% at 90 days, yielding more than 65MPa strength. Also, addition of SF was observed to improve flexural strength of concrete samples up to a 4.3% at the age of 28 days, enabling the manufacture concrete mixtures apt for structural use.
Coal ash use as a cement replacement in concrete production
Authors: Bostanci S C
Published: May 2020

Ordinary Portland cement (OPC) is the main contributor of concrete CO2 emissions amongst concrete constituents. Use of alternative cementitious materials is highly encouraged to lower environmental footprint of concrete production. Local waste materials could be a feasible approach in terms of economic and environmental sustainability due to local availability. In this study, coal ash waste was used as a Portland cement replacement by 10% and 20% for the production concrete mix concrete mix with 28-day design strength of 45 N/mm2. Developed mixes were tested against various engineering properties including workability, bulk density, compressive strength, sound permeability, thermal conductivity, water permeability and porosity. Results showed that coal ash incorporated mixes had slightly lower slump values with slightly lower fresh density. Hardened properties including bulk density and compressive cube strength were reduced slightly for CA mixes. Other hardened properties showed that CA mixes had more compact structures compared to conventional mix. Therefore, CA mixes showed enhanced sound permeability, thermal conductivity, water permeability and porosity.
Seismic Design of Mid-Rise Reinforced Concrete Structures According to TEC 2007 and TBEC 2018
Authors: Derogar S , Safkan I , Odabas B
Published: May 2020

Reinforced concrete (RC) structure are widely used structural system in buildings across the Turkey. The new Turkish standard on earthquake, TBEC 2018: Turkish Building Earthquake Code, was published on 2018 which is replaced for the old earthquake code, TEC 2007: Turkish Earthquake Code-2007. This paper aims to present a comparison between the seismic design provisions of these two codes for the design of mid-rise RC structures. The code provisions in both codes are evaluated and differences in terms of ductility and strength for the design of mid-rise RC structures are highlighted and presented. It was shown that the design base shear is higher when using TBEC 2018 code. A 4-story building is designed according to both codes and then the performance of the structure was evaluated. Due to differences on allowable drift limit, the R and Cd factors, the structure showed different behaviour when design according to both codes which are discussed in detail in this paper. A cost analysis was also carried out and compared for both buildings.
Influence of fillers on structure and behaviour of gypsum mortars
Authors: Doleželová M , Krejsová J , Scheinherrová L , Vimmrová A
Published: May 2020

Gypsum mortars with different types of lightweight fillers were studied. The importance of gypsum as one of the most environmentally friendly building binder increases nowadays and new ways of its utilization are searched. Using of fillers in the gypsum is generally not necessary, because gypsum does not shrink, but they can be used for economic reasons or to improve the thermal properties or fire resistance of the gypsum material. We studied the structure and properties of the gypsum mortars with three types of lightweight fillers (expanded perlite, expanded clay aggregate, recycled PUR) and compared them with the gypsum mortar with siliceous sand. The SEM analyses were performed together with the mechanical tests. The roughness of the fillers surface and its influence on the structure and properties was studied by confocal laser scanning microscopy. It was found, that the type of the filler has principal impact on the microstructure of gypsum mortars and their properties.
An experimental study on the behavior of fiber-reinforced concrete flexural members under cyclic loading
Authors: Gatabi H R , Celikag M , Bengar H A
Published: May 2020

An experimental work was performed to address the cyclic performance of reinforced concrete flexural members containing steel, PVA, and Forta-Ferro fibers. Four full-scale reinforced concrete flexural members having the same geometry were subjected to a one-point bending test with slow cyclic loading. One of the four specimens was a control specimen with 0% fiber volume fraction (Vf), and the other three contained 1.5, 0.6, and 1.5% Vf of steel, Forta-Ferro, and PVA fibers, respectively. The ultimate resistance, ductility, stiffness, dissipation of energy was studied, and the influence that different fibers had on the cyclic performance was evaluated. In general, the cyclic performance of the reinforced concrete flexural members improved by adding fibers, leading to higher ultimate displacement and maximum strength value.
Integrating AHP and GIS as a decision-making tool for the optimal allocation of wind farm: A case study of Syria
Authors: Habib M , Matouk A
Published: May 2020

Nowadays, renewable energy is commonly applied to ensure a sustainable development and minimize the reliance on fossil fuels. Wind is considered as one of the most significant inexhaustible sources of energy for power generation through turbines. However, choosing an appropriate site of wind farm and designing a turbine array to fit it are a key issue to success as expected. Geographic Information Systems (GIS) technology has been widely accepted in a number of areas as a decision support system based on analyzing geospatial data to facilitate reaching desired results in shorter time and less cost. The process of establishing the best-suited location of wind parks require analysis of spatial multi-criteria within a GIS environment using the Analytic Hierarchy Process (AHP). This research focuses on defining the main factors that influence wind energy development and presents GIS-based land suitability analysis model to determine the optimal allocation of wind farm in Syria. As a part of this study, the procedure of designing geodatabase for wind power plants is illustrated that includes conceptual, logical, and physical design phases. The results show efficiency of the integrated technique in site suitability evaluation of the presented case.
Estimation of compaction characteristics of soils using Atterberg limits
Authors: Hussain A , Atalar C
Published: May 2020

Soils are mostly used construction materials. Naturally occurring soils when are used as a construction material their engineering properties need to be determined and they mostly need to be compacted for the improvement of their engineering properties. The determination of these engineering properties becomes a vital process for the successful design of any geotechnical structure. Testing the properties of compaction, optimum water content (OWC), and maximum dry density (MDD), requires high amount of work and consumes a large amount of time in the laboratory. In this paper, an attempt to develop predictive models between liquid limit, and compaction test parameters is made. To achieve this purpose, 8 samples of North Nicosia Kythrea group soils in North Cyprus were subjected to Atterberg limits and compaction laboratory tests. The soils were tested using standard Proctor compaction tests. Stepwise multiple linear regression analyses were carried out on the experimental data and predictive models were developed in terms of liquid limit (LL). Their compaction results were used to validate the proposed models. According to the findings, the R2 values of the models suggested are over 75% and the error variation between the predicted and experimental compaction characteristics values was found to be below ±1. It has been shown that these models will be useful for a preliminary design of earthwork projects which involves Nicosia soils in Cyprus.
A comparative study of critical failure surface determination in slope stability assessment
Authors: Iravanian A , Shlash A
Published: May 2020

Slope stability analysis and design of manmade slopes has always been a challenging geotechnical problem. Different methods have been developed and created to examine two and three dimensional slope models based on various methods of assumption and assessment. Throughout this study two limit equilibrium, and finite element methods has been used to examine the stability of the slope and to determine the critical slip surface of failure by using PLAXIS, FLAC/Slope and SLOPE/W software programs respectively. Different values of shear strength parameters were chosen to investigate the efficiency of these methods. Various values of unit weight, cohesion, internal friction angle, and their impact on the safety factor were examined. Comparing the results for factor of safety indicated that finite element calculation used in PLAXIS gives more conservative results by 0.5% compared to SLOPE/W program. FLAC/Slope was observed as the most complicated software and finite difference method generally gave the lowest value for factor of safety in comparison with the other methods. Impact of internal friction angle, unit weight, and cohesion on length of failure arc was also evaluated, and no significant relation between length of failure arc (La) and safety factor was detected.
Swell and compressibility characteristics of expansive clays in north Cyprus
Authors: Iravanian Anoosheh , Abdeh Amr
Published: May 2020

Expansive clays in semi-arid regions are known as problematic soils especially for low weight civil structures. Volume change is a critical issue, therefore determining expansive clays and quantifying their expandability, retractility and strength is a major step to be considered in geotechnical engineering. This research provides a study on the behaviour of expansive clays done under different geotechnical laboratory experiments on four different types of expansive clayey soils brought from various areas in Northern Cyprus, aiming to prepare a soil-properties map in these regions. Fundamental assessments were performed for determining soil index properties. Swell and consolidation behaviours were determined using one-dimensional oedometer apparatus. The results showed that the rate of the expansiveness of sample the bentonitic clay samples were the highest for the predicted ultimate swell with expandability index categorized as very high. Also, these samples showed the largest compressibility upon the consolidation test results. The results obtained were used to construct a relationship between compression and plasticity Index.
Acoustic and structural design of a highway noise barrier
Authors: Kesten S , Umut Ö , Ayva B
Published: May 2020

Highway noise barriers are designed to mitigate the effects of traffic noise along the highway. Noise barriers primarily block the direct path of the sound between the source on the highway and the receiver exposed to the sound. Noise mitigation capability, aesthetics, cost and constructability and structural capacity against wind and earthquake loads are critical parameters to be considered in noise barrier design. The height and length of a noise barrier are determined by acoustical considerations, aesthetics and cost. In addition, the structural design of the noise barrier should meet the established standards. The aim of this study is to evaluate the noise mitigation capabilities, aesthetic features and costs of acoustic designs for the residential buildings located near the urban highway and evaluate the structural performances against wind and earthquake. Through the interviews, the designs higher than 10m are not found acceptable by the residents and also due to the aesthetic concerns the upper part of the noise barrier is set to be constructed as glass. Therefore, the noise reduction capabilities and construction cost and the alternatives that complies with the constraints are determined and the corresponding costs are calculated accordingly. Noise simulation software is used to identify the effectiveness of selected noise barriers and structural analysis and design software is used to evaluate the structural performance. The results show that designed precast lightweight concrete and glass composite noise barrier meet the required noise reduction goal along with a resilient structural performance and affordable cost.
Adaption of construction management aspects and building economic principles to prevent cost overruns in modern timber construction
Authors: Koppelhuber J , Bok M W
Published: May 2020

The timber construction industry is subject to continuous development and steady modernisation worldwide. This leads to a compelling necessity regarding highly industrialised and standardised processes – both technological and economical – along the value chain of today’s timber construction. Within this field innovative materials and products (such as cross laminated timber – CLT) in combination with a deeply rooted systematic approach are used to create large span and multi-storey timber structures. The results are displayed in an increased use of (partially) automated machines and production plants, novel (semi-)prefabricated components as well as complex software solutions. However – next to numerous technical researches – numerous aspects within construction management and building economics require intensive investigation. Since the influencing factors from economical point of view have been criminally neglected over the past decades it becomes apparent that aspects such as cost planning and estimation, invitation and call for tender as well as cost calculation of timber construction projects demand comprehensive research. Therefore, an outstanding and all-encompassing investigation has been carried out over the past 6 years in Austria at the University of Technology in Graz [1] to identify, develop and implement building economic principles and relating tools focussing exclusively on timber construction. Therefore, the emphasis was set on the development and practical implementation of timber-specific solutions in order to avoid cost overruns and hidden costs during design, construction and use. Possible approaches to solve this lack of economical and operational instruments in timber construction are discussed in this paper.
Bio-precipitation of CaCO3 for soil improvement: A Review
Authors: Miftah A , Khodadadi Tirkolaei H , Bilsel H
Published: May 2020

The bio-mineralization of calcium carbonates is an innovative and eco-friendly technique for improving soil, which has recently become increasingly popular in the field of geotechnical engineering. Different bio-cementation methods are employed for improving granular soils, including microbially-induced CaCO3 precipitation (MICP) and enzymatic-induced carbonate precipitation (EICP). These methods offer innovativeness, effectiveness and sustainability when applied in geotechnical engineering, and have been suggested as possible solutions for various different geotechnical issues. More research has been conducted into MICP compared to EICP. Nevertheless, urease sourced from plants likely offers many benefits over the use of bacteria urease in bio-cementation processes. The present study reviews the mechanisms, possible areas for implementation, related benefits and drawbacks of the bio-cementations techniques. Additionally, it will concentrate on the techniques used in the precipitation of CaCO3 involving the urease hydrolysis of urea. The study findings will enhance the comprehension of biotechnical mechanisms and ensure that geotechnical specialists are suitably informed with up-to-date knowledge on this subject.
Assessment of Bedestan (St. Nicholas Church) on the first decade of conservation works
Authors: Mısırlısoy D , Bilsel N , Safkan I
Published: May 2020

St. Nicholas Church (Bedestan) is one of the most significant monuments located exactly in the centre of the walled city of Nicosia, in the Selimiye Quarter. The significance of the heritage building lies on its temporal transformation. Bedestan initially built by Byzantines in the 5th century, and was later enlarged during the Lusignan, Venetian, Ottoman and British period. Between 2004 and 2009 had gone through conservation works by United Nations Development Programme Partnership for Future (UNDP-PFF) which is funded by European Union. In 2009 the project has won Europa Nostra Award between 140 projects. The project consisted of both architectural and structural strengthening interventions. The aim of the study is to assess current condition of the structure on the first decade of conservation works. The method had three objectives. Firstly, the literature was reviewed in order to understand the historical process of the building. Then, site survey was completed for further understanding of the applied intervention to the structure. Finally, the current condition of the structure was observed after ten years of completed restoration works. Deterioration on used materials as well as durability of strengthening works was assessed and observations were listed herein.
Geo-ecological assessment of job-related diseases in mono-cities of the Russian Federation
Authors: Zinovyeva E G , Koptyakova S V , Balynskaya N R , Chuprin V V , Luntsova A I
Published: May 2020

The relevance of the study is due to the importance of the health state and the quality of life among the population in connection with the adverse influence of a number of factors (environment, emission from large enterprises, food quality, and natural resources).

In the list of these factors affecting the health of employees working in industrial enterprises, harmful factors of the working environment are very important, the impact of which under certain conditions leads to high morbidity with temporary disability, to the development of work-related diseases. The results of a study investigating the level of work-related morbidity suggest that the number of employees in hazardous and harmful working conditions at industrial enterprises in Magnitogorsk increased to 42.95%. In 2017, the ratio of workplaces of industrial enterprises that do not meet sanitary and hygienic requirements for noise increased; the same variable (ratio) according to the standards of vibration, microclimate, lighting decreased; no deviations were detected in electromagnetic fields (EMF). Chronic work-related pathology in 2017 more often arose due to imperfection of technological processes (36.65% of cases), imperfection of workplaces (30.0%), structural shortcomings of labor facilities (16.65%) and sanitary facilities (6.65%), labour (working) contact with an infectious agent (10.0%). The results of the study can be used to improve programs at the federal and regional levels to improve the environmental situation.
The structure of the manipulators of industrial robots
Authors: Ten T L , Ivanov V L , Kogay G D , Drozd V G , Te A L
Published: May 2020

The paper discusses the specifics of using the technology of applying the force action of servo-drives to manipulator components in accordance with the control signals from the robot control device. Consideration is given to solving the inverse kinematics of manipulators of the robot manipulator in continuous path control. Solving the inverse problem description of dependencies is formed in an analytical and tabular form.
The cost of liquid nitrogen for WBC sessions
Authors: Vasilenok A V , Baranov A Y , Malysheva T A , Filatova O A , Kutyanova L R , Andreev A M , Solonina Y A
Published: May 2020

The first unit for the whole-body cryotherapy (WBC) used liquid nitrogen (LN). Liquid nitrogen has a low boiling point (-196 °C) and a high heat sink capacity (HSC). The HSC of LN is 260 kJ/kg at a temperature level of -130°C. Approximately 600 kJ of heat should be removed from the body surface of a patient during a WBC session. The average heat flux from the body surface makes up 3.4 kW. The use of liquid nitrogen makes it possible to remove heat without complicated equipment. Refusal to use LN is caused by the temperature in the WBC zone (-110 °C). This fact reduces the efficiency of WBC procedures. Cryoagent consumption is 5 times less than the demand in some units with LN coolings.
Energy and environment options of working fluid alternative for different refrigeration configurations
Authors: Tsvetkov O B , Laptev Yu A , Nikitin A A , Mitropov V V , Sharkov A V , Rakhmanov Yu A
Published: May 2020

Hydrofluorocarbons, currently used as refrigerants, in air-conditioning systems, for high-temperature heat pump systems in industrial applications are potent greenhouse gases. Their contribution to climate change is to increase. Future use of the hydrofluorocarbons as the hydrochlorofluorocarbons will be phased down. There are very different options to replace them and only a few pure fluids possess the combination of chemical, environmental, thermodynamic, and safety properties necessary for a working fluid. Low global warming potential refrigerants are anticipated to be the refrigerants of choice in industrial applications.
A secondary heat effect on the properties of K70 strength class steel for trunk pipelines
Authors: Sharapova D M , Ganzulenko O Y , Sharapov M G
Published: May 2020

The article presents the results of the technological weldability studies for K70 strength class steel. A gradation of the studied semi-finished products by their repairability (by the number of the allowed local reheat of the material during the welding and repair processes) is proposed. The viscosity reducing of the metal in the overheating zone, determined by the magnitude of the impact test with Charpy samples at the temperature – 40° C was a basis for the gradation condition. The influence of the welding heat input and the number of reheats on the HAZ metal viscosity is established. Thus, the obtained results allow us to state the low technological weldability of this steel, taking into the account such an important indicator as the repairability of the material.
Energy efficient technology of waste management by micro-cogeneration
Authors: Rakhmanov Y A , Sergienko O I , Gorbunov G N
Published: May 2020

The paper considers possible options for energy-efficient waste management technologies using micro-cogeneration. A typology of energy technologies with micro-cogeneration is proposed depending on the main method of disposal, type of reactor, products of the implementation of the main recycling process, as well as processes and equipment of micro cogeneration technology. A brief overview of the current market situation and trends in the development of energy technologies for waste management is presented. The proposed typology and block diagram can be used in choosing rational energy-efficient technologies for waste management.
Environmental assessment of the Akmola region territories relative to the exposure to diseases of the population by the sigmal deviation method
Authors: Kurmanbayeva A S , Kakabayev A A , Bayazitova Z E , Baikenova G E , Sharipova B U
Published: May 2020

This paper presents the statistical indicators of the population’ sickness in various districts of Akmola region. The object of the work is to conduct an environmental assessment of Akmola region’s districts on the relative risk of morbidity. The following morbidity indicators were studied: blood, blood-forming organs and individual disorders involving the immune mechanism; respiratory organs; oncopathology; digestive organs and general morbidity. The sigmal deviation method was used to find out environmental assessment and ranking of territories. The conclusion is made about the importance of risk assessment for environmentally related diseases for ranking territories, identifying crisis zones and ensuring the well-being of the population. It was revealed that the territory of Akmola region has an uneven anthropogenic impact. It is shown that in areas with a high level of atmospheric pollution and adverse water supply conditions, the medical and environmental situation is extreme or critical. The necessity of constant monitoring of the incidence rate for environmentally caused diseases and the adoption of environmental measures in the identified crisis areas is substantiated. The methods for assessing the risks of morbidity considered in the article can be used to improve the activities of the executive branch of Kazakhstan.
Ecological and economical assessment of efficiency of application of alternative energy sources to achieve the goals of the Climate Strategy of St. Petersburg
Authors: Savoskula V A , Sergienko O I , Pavlova A S
Published: May 2020

The paper considers the procedure and methodology for assessing the environmental and economic efficiency of using alternative energy sources installed at industrial enterprises, which can significantly reduce climate risks by reducing greenhouse gas emissions in replaced sources. Based on the proposed methodology, the costs of introducing a hybrid solar installation at an electronic equipment manufacturing enterprise were determined, resource efficiency indicators of efficiency and environmental impact, as well as the cost of generated energy, were calculated. It is shown that the application of the methodology will contribute to the selection of the best available technologies for alternative energy and the achievement of the goals of the Climate Strategy of St. Petersburg.
Investigation of the influence of distribution of heavy metals from construction waste disposal on plant associations of adjacent ecosystems
Authors: Dinkelaker N V , Ovsyuk E A , Sinelnikova N A , Muraviev I A , Dinkelaker N F J , Semenova T S
Published: May 2020

The question of influence of distribution of pollution of soils by heavy metals from the landfill on the soil-plant complex of natural ecosystems in the zone of influence of object is investigated. The presence of increased bioaccumulation of heavy metals of certain specialized ecological groups of plants – submerged macrophytes and weed–ruderal plants was revealed. Specificity of accumulation of heavy metals is not a property of plant life forms. However, within plants of one life form there are species with an increased ability to selective accumulation of individual heavy metals, which is especially pronounced in mosses. The results obtained can be used to improve the efficiency of bioengineering protection of the natural environment through environmental planning of landscapes in the areas contaminated with heavy metals around landfills and other industrial facilities.
Modeling the crystallization process of an eutectic solution in cold accumulators of a refrigerated truck
Authors: Belozerov G A , Babakin B S , Suchkov A N , Makarov B A , Babakin S B
Published: May 2020

The duration of crystallization process of an eutectic solution of an infinite plate may be presented as a sum of three components: duration of the cooling process of the eutectic solution of liquid phase τ1
from initial temperature tI
to the crystallization beginning; duration of crystallization process τ2 and duration of the precooling process of solid phase τ3 to certain final temperature t
f in the plate center.
Sustainable Concrete in Transportation Infrastructure: Australian Case Studies
Authors: Gharehbaghi Koorosh , Rahmani Farshid , Paterno David
Published: May 2020

Whilst generally concrete and steel are the most common substances for civil engineering construction, new trends and development such as sustainable and green material have a lesser effect on the environment. Typically, approximately 90% of a concrete structure’s CO2 emissions are a result of the energy consumed during its life, there is much that can be done to reduce that 10% associated with its construction. Thus, innovative engineering materials, such as Recycled Concrete (RC) have emerged with the potential to influence the future of an environmentally sustainable construction industry. This research investigates the RC as the basis of sustainable concrete for civil engineering construction such as roads, rail and so on. Furthermore, number of examples, 6 roads and 6 rail segments in Sydney, were reviewed. Overall, this research found that for the 6 road and rail case studies generally only RC is utilized as the basis of sustainable material. Although, this is a very small sample, however, a pattern can be noticed. Unfortunately, the pattern is the lack of innovative sustainable material other than concrete for such transportation infrastructure. Appropriately, further investigation is required to review the possibility of other sustainable materials including those incorporating waste-by products as the basis consolidated sustainable material usage in transportation infrastructure.
A Study of the properties and microstructure of high-magnesium nickel slag powder used as a cement supplement
Authors: Oksri-Nelfia L , Akbar Reynaldi , Astutiningsih Sotya
Published: May 2020

This research aims to use high-magnesium nickel slag crushed into a powder as a replacement for cement and to study their properties and microstructure in concrete. The particle diameter of the nickel slag powder was obtained lower than 75 μm after a process of crushing and sieving. The specific areas, absolute dry densities and particle size distribution (PSD) were analysed to obtain the physical properties of the material. The techniques applied to study their chemical and mineralogical composition were the X-Ray Florescence (XRF), the Scanning Electron Micrograph (SEM). The OPC type 1 was used as a reference in comparison to the experimental material of this research. Without a chemical admixture, the compressive strength of concrete after 28 days is fc’ 30 MPa and the specific surface area is 4360 cm2/gr. The compressive strength of high-magnesium nickel slag powder is capable of replacing cement by 20% without altering properties of concrete. According to the XRF technique results, the nickel slag contains silica, calcium, magnesia, and alumina. Furthermore, the image of the SEM-EDS illustrated the slag particle to be sharp, irregular, and containing calcium, silicon, alumina, oxygen, and magnesium. This result confirmed that the XRF technique and SEM-EDS were accurate.
Exploring the Mechanism of Residential Attractiveness in Compact Urban Areas – a Case Study of Hong Kong
Authors: Bai Yunxi , Song Jusheng , Wu Shanshan , Lo S M , Bai Gang
Published: May 2020

Compact cities adopt high density, mixed land use and transit-oriented development (TOD). For sustainable development, compact development reduces the use of automobile and lessens the overdevelopment of land resources. For solving urban sprawl and housing shortage, more and more metropolises have adopted compact development. Academics, planners and policy makers mainly focused on evaluating the impacts of neighborhood attributes on housing prices and residential movements. Few have examined the relationships between residents’ demand and residential attractiveness in compact cities. Therefore, this study develops Residential Attractiveness Evaluation (RAE) Model to evaluate the attractive degree of urban areas based on residents’ demand in compact cities. Hong Kong is chosen as the study area which is a typical compact city. The results show that districts near the CBD and both sides of Victoria Harbor have highest residential attractiveness than other areas. Community planners and policy makers should consider residential attractiveness based on residents’ demand in efforts to promote sustainable development. Residential attractiveness is the foundation of residential land use planning and policies. Planners in compact cities should adopt various planning strategies according to different residential attractiveness. Moreover, residential attractiveness is the benchmark of evaluating residents’ satisfaction of new residential planning and policies.
The Same-floor Drainage for Independent Retrofitting of the Existing Apartment Buildings without S-I System in China
Authors: Ning Zhu , Yong Jiang , Qiang Wang , Wenmin Guan
Published: May 2020

By 1998 the total floor area of urban residential buildings was 9.59 billion square meters in China. In this period, most of the apartment buildings in China adopted brick-concrete structure or shear wall structure without SI-system, and limited the integrating means of retrofitting and reuse. Because of the strict control of area standard in urban residential construction at that time, the toilet area is always too small to carry the contemporary life style, which takes the first difficulty within independent retrofitting of the apartment building. Since the same-floor drainage system is widely used many new built apartment buildings, this paper aims to research and develop this system into retrofitting of the existing apartment buildings without S-I system in China. Based on the analysis to the household plans and their retrofitting design, two kinds of same-floor drainage systems are employed within the toilets, solve the problems of pipe connection, floor elevation and waterproof, and succeed to improve the function and space use of whole household.
Factor Analysis of Service Quality of Provincial Contractors to Owner Satisfaction in Construction Projects in Thailand
Authors: Ngowtanasuwan Grit
Published: May 2020

Service quality in construction projects involves the project owner’s perception of the process in terms of interactions, activities, and the attainment of acceptable levels of performance from construction activities. The purpose of this study is to present a factor analysis of service quality of provincial construction contractors in north-east Thailand that influences the satisfaction of project owners, by using Exploratory Factor Analysis (EFA). A total of 132 questionnaires, completed and returned by project owners, were analyzed to confirm the factors. The research found the service quality of the provincial contractors comprised of three factors, namely: (1) empathy, (2) responsiveness, and (3) tangibles, respectively. Guidelines for strategy for improving the service quality of provincial contractors are discussed and presented in the results of this research paper.
Effect of IR Drop on Reinforced Concrete Corrosion Measurements
Authors: Babu U. Raghu , Kondraivendhan B.
Published: May 2020

The ohmic voltage drop (IR) due to the high resistivity of concrete needs to be considered while monitoring the corrosion performance of rebar embedded in concrete. It helps to evaluate the corrosion condition precisely. Concrete mixes were contaminated with chlorides, sulphates, and a combination of chloride plus sulphate solutions as mix water. To assess the IR drop error in corrosion measurements caused by concrete with different salts, linear polarization resistance values were measured with and without IR compensation. The results indicate that the concrete contaminated with 5% of chloride has shown higher error as compared to 2% of sulphates, due to high corrosion current density. However, from the results of chloride and chloride plus sulphate contaminated concrete, it is also confirmed that the IR drop error is not absolute to determine the solution resistance. The higher corrosion in chloride contaminated concrete as compared to chloride plus sulphate contaminated concrete is also observed due to the availability of high chloride concentration. The results of the present study are suggested that the IR drop compensation should be considered when the reinforced structures are exposed to chloride and sulphate environment.
Properties of Fine-Grained Concrete Mixtures during the Construction of Monolithic Structures
Authors: Aruova L B , Ospanova Z N , Gordienko B S , Alibekova N T , Kalieva Zh E , Urkinbaeva Zh I , Nurbaeva M N
Published: May 2020

The article presents the results and methods of studying the rheological properties of fine-grained concrete mixtures with various additives, as well as the regression equation obtained by calculations using the apparatus of mathematical analysis, which shows the significance of the parameters included in the process of compaction of the ICZB. These data are necessary for the correct design and selection of sealing mechanisms in order to obtain the design physical and mechanical properties of ICZB. In many regions of the world there is an acute shortage of high-quality raw materials for large aggregate in conventional concrete, which necessitates its transportation over distances from 400 to 1000 km. In this regard, the cost of one cubic meter of coarse aggregate in many regions is 2-3 or more times higher than the cost of sand, the deposits of which are more common. In addition, obtaining the desired fractions of quality aggregates requires artificial addition and fractionation of the resulting granules. The experience of using ICZB for the manufacture of parts and structures at the plants of ZHBK gave positive results, but in mass construction (hydraulic), he did not get spread due to insufficient study of physical and mechanical properties, weak efficiency of existing vibration equipment, insufficient development of new technological equipment for laying and sealing. In this regard, we believe that the research aimed at studying the physical and mechanical properties of ICZB and the further development of technological equipment, methods of laying and sealing for their widespread implementation, determine the relevance of this problem.
Packing Structure of Binary Particle Compacts with Fibers
Authors: Boribayeva A , Zharbossyn A , Berkinova Z , Yermukhambetova A , Golman B
Published: May 2020

Fibers have been used to improve the mechanical properties of the asphalt paving mixture. It is known that the enhancement of powder compact mechanical properties is related to the compact packing microstructure. This study focuses on the evaluation of the packing microstructure of powder compacts produced from ternary mixtures of spherical particles and fibers. The discrete element method is employed to generate the compacts of particle mixtures of different compositions under gravity. The compact microstructure is quantitatively characterized by utilizing the developed image analysis technique to approximate the size distribution of voids among particles in X, Y and Z directions. As a result, the denser packing was obtained with a greater fraction of small spherical particles. The inclusion of fibers resulted in the high-density compact with uniform distribution of small size voids.
Shear Strengthening of T-Section RC Beams Using Double-Side Externally Bonded CFRP
Authors: Alfarra Hazem , Maalej Mohamed , Barakat Samer
Published: May 2020

This paper aims at investigating the effect of S-wrap EB-CFRP to shear-strengthen RC T-beams. The experimental program included seven 3.3m-span T-beams that were tested under three-point loading. The specimens were divided into two major groups, including four specimens with no steel stirrups (Group 1), and three specimens with steel stirrups at half of the effective depth (d/2) center to center spacing (Group 2). Five of the seven specimens were strengthened in shear using S-wrap EB-CFRP strips used at d/4 and d/2 spacings. The shear capacity, maximum deflection under the applied load, failure mode, and the strain development in the CFRP strips, steel stirrups, and the main tensile reinforcement were reported in this paper. The overall results show that the addition of EB-CFRP strips to T-beams is an effective method of enhancing the shear capacity of T-Beam in the absence of steel stirrups. With the presence of steel stirrups in the T-beams, the contribution of the EB-CFRP strips in enhancing the beams’ shear capacity appears to be small relative to that of steel stirrups.
Effectiveness of Splitter Plate in Suppressing the Flow-Induced Vibration of a Circular Cylinder
Authors: Kamarul’Arifin Ilya Qurratu’Ain Binti , Quen L K , Kang H S , Tan L K , Othman Nor’ Azizi bin , Siow C L
Published: May 2020

The effectiveness of splitter plate as suppression device in reducing the flow-induced vibration (FIV) of a circular cylinder was conducted experimentally. The parameter used in this experiment is the gap separation between splitter plate and the circular cylinder (G/D). The control element of gap separations are varied from 0.5 to 2.0. The experiments were conducted in the wind tunnel which was free from external wind conditions at Aeronautical and Wind Engineering Laboratory (AEROLAB), UTM Kuala Lumpur. A supporting structure was designed and fabricated with the purpose to allow free vibration induced by wind on the circular cylinder. The results were analysed through the response of amplitude and power spectral density of the circular cylinder with splitter plate and compared with bare circular cylinder. For the gap separations of G/D = 1.0, 1.5 and 2.0, the vibration of the circular cylinder were successfully suppressed. The optimal distance for gap separation was at G/D = 1.5 with suppression effectiveness of 82%. For G/D = 0.5, on the contrary, the vibration of the circular cylinder was amplified. As conclusion, splitter plate can function to suppress as well as amplify the vibration of cylinder, depending on the gap separation.
Analysis of Infilled Masonry Wall in Steel Frame Subjected to Lateral Loading by Experiment and FEM Software
Authors: Bhosale Suraj D , Desai Atul K
Published: May 2020

This paper describes the behaviour of infilled masonry wall in steel frame subjected to lateral loading. Construction of RCC structure is quite slower than Steel structure, though the cost of steel structure is high but time required for construction is less, moreover for temporary structure steel member and section are use on large scale as it can be reused also. In this study a rectangular steel frame of IS section ISMC 250 is made and lateral loading is applied through jack. Frame is infilled by fly ash units with thin mortar joint. Axial load is also applied on frame simultaneously, during experiment and data is analysed, same full scale model is simulated in FEM tool and result were compare and found that they valid each other, it was observed that in steel frame initially bond between masonry and steel frame section get separated and it try to overturn the masonry wall from toe and debonding at toe initiated but as it is bounded and lock in channel section it stress transfer to heel side of masonry and all stress is concentrated on heel and heel crushing take place.
Research on Magnetic Induction Detection of Steel Bars Corrosion
Authors: Yang Zengquan , Xiong Jinsong , Chen Chuan , Xu Jun , Zhang Jiulin , Ye Huarui
Published: May 2020

Reinforced concrete structures are widely used in modern buildings. However, the structural damage caused by the steel bars corrosion seriously affects the building remaining life. The reinforcement corrosion in concrete is slow, so the long-term detection of reinforcement corrosion is very important. The development of reinforcement corrosion detection equipment in China is slow, which cannot meet the application requirements of domestic concrete structures, this paper proposes a non-contact magnetic induction detection method for reinforcement corrosion. Through theoretical analysis and experimental design, a simple model is built and simulated. Simulation results of single and multiple steel bars corrosion to verify the feasibility of the method. This paper provides theoretical support and technical solutions for the operation state detection of non-contact reinforced concrete, and makes contribution to the non-contact magnetic induction detection technology.
Automatic Crack Detection for Concrete Infrastructures Using Image Processing and Deep Learning
Authors: Kim Cuong Nguyen , Kawamura Kei , Nakamura Hideaki , Tarighat Amir
Published: May 2020

Automatic crack detection is a main task in a crack map generation of the existing concrete infrastructure inspection. This paper presents an automatic crack detection and classification method based on genetic algorithm (GA) to optimize the parameters of image processing techniques (IPTs). The crack detection results of concrete infrastructure surface images under various complex photometric conditions still remain noise pixels. Next, a deep convolution neural network (CNN) method is applied to classify crack candidates and non-crack candidates automatically. Moreover, the proposed method is compared with the state-of-the-art methods for crack detection. The experimental results validate the reasonable accuracy in practical application.