|Author(s): Saif Salah Alquzweeni|
|Pages: 1-13||Paper ID:154006-3939-IJCEE-IJENS||Published: December, 2015|
Abstract:-- In this investigation, the effects of elevated temperatures of 300, 550, 750°C for 1.0 hour at different ages of 28 , 56 and 90 days on the main mechanical properties of high strength concrete are studied. After burning, the concrete specimens were quenched in a water tank to provide the maximum shock due to sudden cooling. This study presents the effort in applying neural network-based system identification techniques to predict the mechanical properties of high strength. Back-propagation neural networks model is successively developed, trained, and tested using actual data sets from experimental. The parametric study shows that temperature is the most significant factor affecting the output of the model. The results showed that artificial neural networks (ANN) has strong potential as a feasible tool for predicting compressive strength of concrete after exposure to fire flame.
|Keywords: Artificial neural network, Burning, High strength of concrete and Predicting.|
|Full Text (.pdf) | 770 KB|
|Author(s): Diego de Quadros Melo, Carla Bastos Vidal, André Leandro da Silva, Giselle Santiago Cabral Raulino, Adriana Dervanoski da Luz, Cleuzir da Luz, Pierre B. A. Fechine, Selma Elaine Mazzeto, Ronaldo Ferreira do Nascimento|
|Pages: 14-25||Paper ID:155505-1506-2929-IJCEE-IJENS||Published: December, 2015|
Abstract:Lignocellulosic fibers were subjected to an acid and alkaline pre-treatment and used as adsorbent of copper, cadmium, lead and nickel metal ions from aqueous phase. Adsorption process was carried out in batch conditions and the effects of alkaline treatment were investigated. Homogeneous diffusion of a particle model was used to predict the adsorption kinetics mechanism. Fourier transform infrared (FTIR) spectrometry analyses were applied to identify the groups that participated in adsorption process and suggest its mechanisms. The Langmuir isotherm provided the best fit for the experimental data. A mathematical model was used to simulate the breakthrough curves of metal ions in multi-element adsorption column taking into account the influences of external mass transfer and intraparticle diffusion resistance.
|Keywords: Lignocellulosic Fibers; adsorption; metal ions; mathematical modeling; numerical simulation|
|Full Text (.pdf) | 844 KB|
|Author(s): Veronica López, Julia Romero Lucchese, Wagner Augusto Andreasi|
|Pages: 26-31||Paper ID:153206-7979-IJCEE-IJENS||Published: December, 2015|
Abstract:The thermal comfort conditions in a given environment influence the performance of its occupants. Therefore, an effective evaluation is an important issue, particularly in schools. This paper presents the results of thermal comfort research carried out in naturally-ventilated high-schools of Paraguay, where no similar study has been performed. Data was collected in three classrooms, of three different schools, through the monitoring of climatic variables and application of questionnaires, which occurred simultaneously. The study compared three thermal comfort assessment methods by obtaining the indices: Predicted Mean Vote (ISO 7730 method), Thermal Sensation Vote (ISO 10551 method) and Andreasi's TSV, whose algorithm was specifically developed to predict sensation votes in hot-humid climates. Three field campaigns were carried out during Summer and a total of 256 questionnaires were obtained. Andreasi's algorithm successfully adjusted PMV to the hot-humid context, improving its performance by 7% to up to 17%. Outdoor climate variables were proved to be of great relevance in the assessment of the schools. Students seated near the external wall more often declared thermal discomfort as they experienced greater climatic variance than those seated further inside. The high percentage of window area in the classrooms was one of the main factors that resulted in great influence of external conditions in the indoor environment. General design guidelines adequate to hot-humid climate regions are proposed in this study.
|Keywords: Predictive ability, comfort index, summer, field experiment.|
|Full Text (.pdf) | 474 KB|
|Author(s): SyamsulArifin, Mary Selintung, Lawalenna Samang, Tri Harianto|
|Pages: 32-46||Paper ID:150706-8383-IJCEE-IJENS||Published: December, 2015|
Abstract:In analysing of asphalt mixtures, contributions of air, binder and aggregate to the total volume of compacted mixtures has been recognized as a significant factor. The purposes of this study are: (1) to find out which of quarry has an aggregate with the best technical qualities among four quarries in Palu city. Moreover, scientific reasons have to be derived to answer why such technical qualities are occured, (2) to analyse influence of effective specific gravity of mixed aggregate (Gse) on VMA and Modulus Elasticity (Sme) of Asphalt Concrete Wearing Course (AC-WC) at several levels of asphalt mixture , and (3) to determine effect of the level of asphalt mixture on VMA and Modulus Elasticity at each of Gse value. Technical quality tests were done based on AASHTO and ASTM specification. Identification of miscroscopic structural and mineral geologist of aggregate have been specified under SEM (Scanning Electron Microscopy), EDS (Energy Dispersive X-ray) and Petrography tests. Determination of mixed aggregat gradations were carried out using trial mix analysis, yielding of 5 different types of Gse ie 2.757, 2.733, 2738, 2.731, 2.734 and five types of Superpave gradation. There was a strong relation between aggregates technical properties and micro structural mineral geologist testing results. At some values of Gse, increasing levels of asphalt mixture cause decreasing of VMA and icreasing of Sme. In general Gse contribution to Sme is relatively small, except to the asphalt content of 6% which Gse shows effect up to 68.2%. There was an increasing trend of Sme as Gse is gaining bigger. At all grades of Gse, the entire content of asphalt gives a significant influence on Sme with a contribution of morethan 63%. There is a significant increasing trend of Sme as asphalt content moving bigger.
|Full Text (.pdf) | 1,080 KB|
|Author(s): Moura, Mariangela; Motta, A. L. T. S. ; Noya, M., Soares, Carlos Alberto Pereira|
|Pages: 47-52||Paper ID:151906-7272-IJCEE-IJENS||Published: December, 2015|
Abstract:The current model of energy matrix produces strong impacts on the environment, such as the modification of ecosystems and the air pollution through greenhouse effect gas emissions like CO2, resulting from the burning of fossil fuels. Because of these and other negative human actions on the environment, the planet watches environmental disasters due to climate changes in progress. Thus, the use of alternative energies combined with the rationalization of energy consumption can be directly linked to reducing the emission of pollutants in the atmosphere reducing these negative effects on the environment. The search for better energy performance of buildings must be a constant concern of professionals, through projects aimed at efficient technological solutions based on the full utilization of available natural resources in nature. This efficiency should be based on finding less energy to provide the same amount of energy value. Thus, the article presents a case study conducted at the headquarters of the Secretaria de Estado de Fazenda do Rio de Janeiro (State Department of Finance of Rio de Janeiro), between the current lighting system, consisting of fluorescent lamps compared to Light Emitting Diode - LED bulbs. The case study aimed at testing the efficiency and quality of the light emitted by the LED lamps, compared to fluorescent lamps, and verify by measuring the percentage of savings achieved between the two lighting systems, their performance and index brightness between fluorescent and LED lamps. The study presents a comparative record between the two types of bulbs and should serve as the basis of study for other researches related to energy efficiency, since it provides important data of use between traditional and widely used fluorescent and LED lamps, less uded in function of high cost.
|Keywords: Energy efficiency, Sustainability, Environment.|
|Full Text (.pdf) | 257 KB|
|Author(s): Alberto C. Lordsleem Jr., Fábia K. G. Andrade|
|Pages: 53-59||Paper ID:154206-7878-IJCEE-IJENS||Published: December, 2015|
Abstract:The search for greater efficiency has required the construction companies to make some improvements in management over the long term control of services as well as in quality, to meet the satisfaction of the external customer is the enterprise guarantee of success. The use of subcontractors as an alternative has been adopted in view of implementing the service speed and, it is believed, with the same quality required; Apart from lower overhead costs. Within this context, this work presents and discusses 02 case studies of services provided by subcontractors companies, namely: internal and external ceramic coating, which analyzes the term of office and quality contractor on these services. The results correspond to physical advances from 48.55% to 92.97% for lining service; while for outer covering, advances were 11.57% and 89.69%. Regarding the quality, it is facing execution without excellence, requiring rework and, therefore, additional time and cost before avoided with the use of this hand labor. It is clear, therefore, that the use of subcontractor labors positive, with a view to reducing overhead costs, although its speed has not matched the expected rate; there is also a need for training and constant supervision over the service in order to avoid future rework after the subcontractor demobilization.
|Keywords: Deadline, ceramic coating, management, quality, subcontracting.|
|Full Text (.pdf) | 696 KB|
|Author(s): Ryal-Net, Marcus Balah, Kaduma, Lot Akut|
|Pages: 60-69||Paper ID:151105-1506-9393-IJCEE-IJENS||Published: December, 2015|
Abstract:Building Information Modeling (BIM) is an innovative approach that is gradually being implemented across the globe. BIM aids the visualization of what is to be built in a simulated environment in order to identify potential design, construction or operational problems of a facility. Despite established benefits that BIM offers, the adoption of BIM in the Nigerian Construction Industry has been relatively slow. A field survey was conducted with the use of 90 structured questionnaires; self-administered via stratified random sampling of stakeholders within the Construction Industry in Kaduna State, North-western Nigeria; all structured to identify the respondents’ level of awareness of BIM, and extent of usage of BIM. 43 questionnaires were properly filled and returned. With a response rate of 44.77%, the results were analyzed using the Percentile and Relative Index (RI) methods. As a contribution to knowledge, the paper has established that there is a low level of knowledge of Building Information Modeling (BIM) in the Nigerian Construction Industry which is associated to the low level of awareness and utilization amongst stakeholders. As such, the paper recommended the need for increased awareness and utilization of BIM via the participation of relevant professional bodies; the integration of BIM into the Academic curriculum; and for the Nigerian Government to facilitate the implementation of BIM in Infrastructure projects, in order to ensure adequate knowledge of BIM towards improving productivity and efficiency in the Nigerian Construction Industry.
|Keywords: Building Information Modeling (BIM), Knowledge, Productivity, Nigerian Construction Industry, Kaduna State.|
|Full Text (.pdf) | 771 KB|