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14th International Conference on Non-Conventional Materials and Technologies for Sustainable engineering, NOCMAT 2013

作者： Lima, Paulo Roberto Lopes Filho, Romildo Dias Toledo Da Fonseca Martins Gomes, Otávio 1Post-graduate Program of Civil and Environmental Engineering Department of Technology State University of Feira de Santana Av. Transnordestina S/N-Novo Horizonte Feira de Santana Bahia 44036-900 Brazil Civil Engineering Program/COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil Centre for Mineral Technology-CETEM Av. Pedro Calmon 900 21941-908 Rio de Janeiro Brazil University of Liege GeMMe Georesources and Geoimaging Sart Tilman B52 4000 Liege Belgium

ISBN: (纸本)9783037859810

In this work it was studied the influence of recycled fine aggregate obtained from construction and demolition waste (CDW) on the rheological properties of Portland cement mortars. The CDW was initially separate in their main constituents (mortar, ceramic and concrete debris) at the laboratory and then grinded separately to the sand size in order to generate more homogeneous fine aggregates. The characterization of the natural and recycled sands was carried out through physical tests, X-ray diffraction, scanning electron microscopy (SEM), and image analysis (shape and texture description parameters). A conventional mortar and three mortars containing recycled sands were produced with a sand/cement ratio of 4 and consistency index of 255±5 mm. The consistency was kept constant by ranging the water-cement ratio from 0.58 to 1.14. The rheological study was performed using a rotating viscometer to obtain torque-rotation ratio and to calculate the yield stress and plastic viscosity. The results indicate that the presence of recycled aggregate causes a lowering of both yield stress and plastic viscosity with respect to the mortar containing natural aggregate. © (2014) Trans Tech Publications, Switzerland.

关键词： Mortar

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GIS as a Decision Support Tool in the Area of Influence of the Nuclear Complex Angra dos Reis, Brazil

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Journal of Geographic Information System 2013年第1期5卷 13-23页

作者： Corbiniano Silva Luiz Landau Luiz Claudio Gomes Pimentel Paulo Fernando Lavalle Heilbron Filho Civil Engineering Program Alberto Luiz Coimbra Institute of Post Graduate Studies and Research Federal University of Rio de Janeiro Rio de Janeiro Brazil Mechanical Engineering Program Alberto Luiz Coimbra Institute of Post Graduate Studies and Research Federal University of Rio de Janeiro Rio de Janeiro Brazil National Commission for Nuclear Energy Rio de Janeiro Brazil

The outlook concerning the occurrence of industrial accidents has led to the implementation of response systems based on geoprocessing tools, which are widely adopted in emergency for such ventures, since they have helped and served as a support for decision making, as well as for the preparation of guidelines aimed at managing emergencies. Nuclear power plants, because they constitute types of industrial activities that present dangerous conditions and attention regarding security are characterized as hazardous, especially due to consequences that occurred from large accidents— such as Chernobyl (1986) and Fukushima (2011)—highlighting the importance to its negative impacts, since the occurrence of accidents at nuclear power plants may affect surrounding areas, thus exposing a set of elements that are part of the environmental dynamics that integrates the catchment area where this type of plant is situated. In this way, through an integrated view of the region where the nuclear complex is located in Angra dos Reis City (Rio de Janeiro State) and, also, by aggregating information that portray the geobiophysical reality of its surroundings, several elements were incorporated into a database developed in a virtual environment, in which was produced a geographic information system (GIS) that presents a complex of variables that, once considered, can enhance various analysis in order to support emergency situations and planning, as well as guidelines that help define actions from the occurrence of accidental events at the nuclear plant.

关键词： Industrial Accidents Nuclear Power GIS Planning of Emergency Response Systems

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A feasibility study of recycling of construction and demolition waste for structural purposes

Journal of Solid Waste Technology and Management

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Journal of Solid Waste Technology and Management 2013年第3期39卷 204-213页

作者： Mariano, Leila Seleme Da Costa, Marienne Do Rocio De Mello Maron Braga, Maria Cristina Borba Brasilian Air Force Integrated Air Traffic and Control Center - CINDACTA II Brazil Parana Federal University Department of Civil Engineering Civil Engineering Post-Graduate Program Brazil Parana Federal University Department of Hydraulics and Sanitation Water Resources and Environmental Engineering Post-Graduate Program Brazil Universidade Federal do Paraná Setor de Tecnologia Centro Politécnico - Jardim das Américas CxP 19011 81531-980 Curitiba - Paraná Brazil

The environmental problems related to construction and demolition waste involve their final dis-posal and the use of raw materials. The main goal of this research was to manage on site con-struction and demolition waste and generate concrete for structural purposes by processing concrete and mortar wastes. A Construction and Demolition Waste Management Plan (CDWMP) was developed for this study and applied by means of the implementation of recy-cling procedures. This plan included quantifying wastes and analyzing their generation. The concrete and mortar wastes were separated for recycling to produce concrete in which these wastes, respectively, replaced fractions of coarse aggregate (crushed stone) and fine aggre-gate (sand). Tests were carried out to characterize the resulting concrete and the aggregates used. The strength of the concrete generated varied from 6 MPa to 21.4 MPa, for the same mixture. It was observed that structural concretes can be produced using recycled aggregates, however this cost is higher compared to that of concrete produced with conventional aggre-gates. It was also concluded that despite the cost of concrete production, there were environmental and economic advantages to performing and applying the CDWMP to this specific con-struction site. Copyright © 2013 Widener University.

关键词： Recycling

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Influence of CDW Recycled Aggregate on Drying Shrinkage of Mortar

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Open Journal of civil engineering 2012年第2期2卷 53-57页

作者： Paulo Roberto Lopes Lima Monica Batista Leite Civil and Environmental Engineering Post-Graduate Program State University of Feira de Santana Feira de Santana Bahia Brazil

The use of fine recycled aggregates as raw material in the production of mortars appears as a good alternative to minimize waste disposal, so as to reduce natural resources consumption and to find and supply suitable substitutes for natural aggregates. However, the use of this alternative material in a safe way must be carried out by a wide investigation of its long term behavior. In this way, this paper will examine the mechanical strength, physical properties and drying shrinkage of mortar, which use recycled fine aggregates that have originated from construction and demolition waste (CDW) containing mortar (55%), ceramic (26%) and concrete (16%). Two natural mortars, made with natural sand, were produced with cement/sand ratios of 1:4 and 1:8 (by weight) and a fixed consistency index of 260 +10 mm. Recycled mortar was produced with 50% of substitution rate, in volume, of natural aggregate by recycled one. Results show that recycled mortars present higher total porosity, absorption rate and drying shrinkage than reference mortar.

关键词： Recycled Mortar Construction and Demolition Waste Drying Shrinkage Recycled Aggregate

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Acoustic performance of closing panels used in steel-structured buildings

Acoustic performance of closing panels used in steel-structu...

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18th International Congress on Sound and Vibration 2011, ICSV 2011

作者： Ribas, Rovadávia A.J. Souza, Henor A. Civil Engineering Post-Graduate Program Universidade Federal de Ouro Preto Escola de Minas Campus Morro do Cruzeiro 35400-000 Ouro Preto - MG Brazil

ISBN: (纸本)9781618392596

In this research, it was made the evaluation of the acoustic performance of some closing systems mostly used in steel-structured buildings in Brazil, for instance walls made of the cement plates, precast concrete panels and plasterboard walls. The acoustic performance was evaluated by estimating the sound transmission loss that occurs through them using a simplified graphical method. It was studied the performance of these kinds of panels and their combinations forming double panels, with and without sound-absorbing material between them. Copyright © (2011) by the International Institute of Acoustics & Vibration.

关键词： Precast concrete

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A strategic way for promoting improved seismic resistant techniques to Indonesian builders

A strategic way for promoting improved seismic resistant tec...

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9th US National and 10th Canadian Conference on Earthquake engineering 2010, Including Papers from the 4th International Tsunami Symposium

作者： Wijanto, Sugeng Andriono, Takim Tjondro, Johannes Adhijoso P.T. Gistama Intisemesta Jakarta Indonesia Civil Engineering Department Trisakti University Jakarta Indonesia P.T. Gistama Intisemesta Surabaya Indonesia Post Graduate Program Petra Christian University Surabaya Indonesia Civil Engineering Department Parahyangan Catholic University Bandung Indonesia

ISBN: (纸本)9781617388446

Indonesia is located in a seismically prone area. During the Aceh 2004, Yogyakarta 2006, Padang 2009 earthquakes, many casualties were caused by the collapse of buildings. Due to lack of awareness, knowledge and skills, many of these buildings, particularly non-engineered houses, were rebuilt using non-seismic resistant techniques as used previously. In cooperation with the World Housing Encyclopedia (WHE), a strategic way for promoting improved seismic resistant construction to Indonesian builders has been implemented. Architectural and civil engineering students are involved. A special tutorial is conducted periodically by seismic engineering experts to enable these students to learn practical seismic resistant techniques for designing and constructing single to two storey dwellings as well as multi storey reinforced concrete buildings. During their studies they are assigned to promote these techniques to the community at large and to builders in particular. A student e-network is set up to enable them to exchange ideas and encourage each other. The first phase of this effort is reported in this paper.

关键词： Students

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A neural network modelling of steel joint block shear capacity

A neural network modelling of steel joint block shear capaci...

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9th International Conference on the Application of Artificial Intelligence to civil, Structural and Environmental engineering, AIcivil-Comp 2007

作者： Rodrigues, F. Neto, L. Biondi Da S. Vellasco, P.C.G. De Lima, L.R.O. Vellasco, M.M.B.R. Post-Graduate Program in Civil Engineering Brazil Electronic Engineering Department Brazil Structural Engineering Department State University Rio de Janeiro Brazil Electrical Engineering Department Pontifical Catholic University Rio de Janeiro Brazil

ISBN: (纸本)9781905088201

Despite the multiple failure modes associated to bolted steel joints the block shear failure is frequently the controlling limit state of gusset plates, tension members and coped beam joints. The block shear rupture is characterised by a condition where a steel block area, nearby the holes of bolted joint region, reaches its maximum capacity dictated by a tension to shear interaction. If the joint is loaded beyond this limit a steel block is eventually separated from the main structure. Many models have been proposed to avoid shear block failure in steel design. These models incorporate a combination of the various hypotheses that control the structural rupture. In the majority of cases, it involves a combination of rupture and yielding in the tension and shear planes of the designed joint. Various design formula for this structural engineering problem were proposed all over the years but a closed solution has not yet been reached, due to the influence of several independent parameters. Many studies have already been carried out with the available experimental data, however, non negligible errors are still present in the current design formulae. The main objective of the present paper is to present a back propagation neural network evaluation of the block shear phenomenon. The main neural network input parameters were the geometrical and material variables that control the block shear design. The neural network output parameter was the block shear capacity. The neural network training was based on experimental results present in literature and adopted cross validation techniques to avoid the neural network overfitting. The neural network results were promising, with reduced associated errors and confirmed the possibility of using this methodology to generate trustworthy data. These new data, coupled with the existent experiments, can help the production of more accurate design formulae. © civil-Comp Press, 2007.

关键词： Neural networks

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Finite element modelling of steel beams with web openings

Finite element modelling of steel beams with web openings

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11th International Conference on civil, Structural and Environmental engineering Computing, civil-Comp 2007

作者： Rodrigues, F. Da Vellasco, P.C.G.S. De Lima, L.R.O. De Andrade, S.A.L. Da Silva, J.G.S. Post-Graduate Program in Civil Engineering State University of Rio de Janeiro Brazil Structural Engineering Department State University of Rio de Janeiro Brazil Mechanical Engineering Department State University of Rio de Janeiro Brazil

ISBN: (纸本)9781905088157

Height limitations are frequent in multi-storey buildings due to zoning regulations, economic requirements and esthetical considerations. On the other hand, substantial spaces are normally required to enable the passage of large pipes and ducts beneath steel beams leading to uneconomic floor heights. The most adopted solution is the use of holes at the steel beam webs in order to enable the passage of services. Chung et al. [1], [3] state that nowadays services that require web openings up to 75% of the beam height are not uncommon. These openings could lead to a significant decrease of the beam load carrying capacity depending on the adopted holes shape, size and location. This motivated the present study that used finite elements simulations to quantitative and qualitative evaluates the structural behaviour of steel beams with web openings. This paper presents the developed finite element models using the ANSYS [6] program to investigate the structural response of steel beams with web openings. The analysis incorporated geometric and material non-linearities and were calibrated against numerical and test results to validate the proposed finite element models. The investigation also contemplated the simulations of beams with a series of holes distributed all over their length known as cellular beams. The imulations were centred at the evaluation of the different steel beams with web penings failure mechanisms and the main reasons for yours collapse modes. © 2007 civil-Comp Press.

关键词： Finite element method

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Effect of Ozonation and Biotreatment on Molecular Size and Hydrophilic Fractions of Natural Organic Matter

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ACS Symposium Series 1996年第649期649卷 196-196页

作者： Koechling, M. T. Shukairy, H. M. Scott Summers, R. Department of Civil Engineering University of Cincinnati Cincinnati OH 45221-0071 P.O. Box 210071 United States Post Graduate Research Program Oak Ridge Inst. for Sci./Education U.S. Environmental Protection Agency Cincinnati OH 45268 26 West Martin Luther King Drive United States

The impact of ozonation and ozonation combined with biotreatment on the molecular size (MS) distribution, hydrophilicity, chlorine reactivity and chemical composition of a groundwater natural organic matter was investigated. Chlorination of isolated fractions was conducted under constant precursor concentrations and chlorination conditions. In the untreated solution, the <1K MS fraction was the most reactive to chlorination, and the nonhumic fraction showed the highest bromine incorporation. Ozonation caused a shift to smaller MS and hydrophilic fractions, and from a polyaromatic nature to a polysaccharidal and proteinaecous nature, as measured by pyrolysis-GC/MS analyses, but did not affect the disinfection by-product (DBP) specific yield in the larger MS fractions. It did cause a shift towards more bromosubstituted DBFs. Subsequent biotreatment was most effective in dissolved organic carbon removal for the <1K MS fraction, but did not exhibit selective DBF precursor removal in any fraction.

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THE NO FRAME CONCEPT - ITS IMPACT ON SHIPYARD COST

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NAVAL ENGINEERS JOURNAL 1984年第3期96卷 218-232页

作者： NAPPI, NS WALZ, RW WIERNICKI, CJ Natale S. Nappi:graduated from City College of New York in 1954 with a B.S. degree in civil engineering and received his M.S. in civil engineering from the Polytechnic Institute of Brooklyn in 1959. He began his professional career in 1954 at the New York Naval Shipyard as a naval architect (structures) performing detail structural design and fabrication studies for CVAs LPDs DDs and CGs and eventually became a supervisory naval architect (structures). From 1965 to 1973 he was a member of the staff of the Computer-Aided Design Division at the David Taylor Naval Ship Research and Development Center (DTNSRDC). As such he was involved in the development of the computer structural design tool the SSDP (in association with Frank M. Lev) and automated detail design programs (CASDOS). His current position is Senior Naval Architect Consultant in the structural integrity group of the Ship Structures Division Structures Department DTNSRDC. Mr. Nappi is the author and co-author of numerous technical papers and reports covering a wide spectrum of topics such as automated structural design process design for producibility and survivability material weight and cost trade-off studies and structural weight determination for high performance ships (i.e. SES SWATH HYSWAS). He has lectured on the subjects of design for survivability and ship structures at the Naval Post Graduate School and MIT. He is a member of ASNE ASCE U.S. Naval Institute Sigma Xi and is a registered Professional Engineer in the State of New York. Mr. Nappi was a member of the NAVSEA working commitee for the computer supported design planning effort and is currently a member of the DTNSRDC ASSET Advisory Committee. Ronald W. Walz:graduated in 1974 from Pennsylvania State University with a B.S. degree in civil engineering. He began his professional career in 1974 at the David Taylor Naval Ship Research and Development Center as a structural engineer in the structural design concepts group of the Ship Structures Division Structures Department.

A proposed cost effective alternative to current U.S. Navy structurally configured hulls is presented in this paper. This proposed design for producibility concept involves the elimination of structural stanchions and transverse web frames. The potential impact of this “no frame” concept on structural design, weight and construction and material costs for naval surface frigates and destroyers is reflected in 1) reduced costs for the installation of distributive systems and 2) a reduced number and complexity of structural details providing a more reliable and less costly structure. This study was performed in three parts: 1) Determine the most feasible length between bulkheads without frames; 2) Using this length perform detail weight studies and construction and material costs analysis comparison on a 72-foot long hull module, with and without frames, for a FFG-7, and 3) Estimate the saving in man hours of labor on the installation of distributive systems and shipfitting for an FFG-7. For the feasible length studies on the “no frame” structural configuration, thirty-seven strength, weight and vertical center of gravity studies were performed on two ship classes; twenty-two on the FFG-7 class and fifteen on the DD-963 class. The detailed weight studies and construction and material cost analyses were conducted for FFG-7 “no frame” and “as built” modules. Results indicating the “no frame” concept module was 6.8% heavier and 14.8% less costly than the “as built” module. For the impact of an FFG-7 “no frame” structurally configured hull on the cost of labor required for the installation of distributive systems and for other functional work such as ship fitting, welding, and electrical, this study indicated a reduction of 169,206 labor hours per ship, representing 7.12% of the total required man hours to fabricate an FFG-7 class ship. With the employment of the “no frame” concept, certain areas of significant concern and potential risk were addressed. These include: 1) t

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