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Perfomance based design of building structural frames using static non-linear analysis

Barros, R.C.; Braz César, M.T.
Fonte: Civil-Comp Press Publicador: Civil-Comp Press
Tipo: Parte de Livro
ENG
Relevância na Pesquisa
85.9%
In the design of structures under seismic actions several methodologies can be used to describe the structural seismic response. The recent role of performance based design led to the development and use of methods based on non-linear analysis, namely the so-called pushover analysis. This analysis is a particularly realistic methodology to evaluate the seismic performance of a structural system since the time dependence of the structural behaviour, namely through material and/or geometric non-linearity, is included in the methodology. The pushover analysis is a simplified methodology to obtain the structural response to seismic actions through a non-linear static analysis. This analysis evaluates the performance of the structures through control of its displacements (at local and global levels), still giving information about the ductility and the resistant strength capacity. Several analysis methods have been proposed like the N2-method (Fajfar and Fischinger [1]) that is actually presented in Eurocode 8 (EC8) [2]. The implementation of this methodology in this regulation manifests the relevance of this analysis in the structural design. Therefore, the present study was developed to compile some information about this new dynamic structural analysis and design concept. In this context...

Avaliação de desempenho ambiental em projetos: procedimentos e ferramentas; Design environmental performance assessment - proceedings and tools

Campos, Cláudio de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/04/2007 PT
Relevância na Pesquisa
55.77%
O objetivo desta dissertação é analisar qualitativamente o ferramental disponível para suporte à melhoria de desempenho ambiental no desenvolvimento de projetos, quanto à viabilidade de aplicação à prática projetual corrente no Brasil. A crescente conscientização de que o consumo sustentável dos recursos naturais é freqüentemente ignorado ou mal interpretado nas práticas projetuais, tem levado os projetistas a assumir suas reais responsabilidades e melhorar o diálogo e a interrelação com outros agentes do macro setor da construção civil. Neste contexto o trabalho procura discutir conceitos básicos sobre o paradigma do projeto orientado ao desempenho, o processo de projeto integrado, bem como assuntos relacionados à indústria da construção. São revistos temas teóricos afetos ao desempenho construtivo, avaliação do ciclo de vida, e ainda aos impactos ambientais decorrentes das atividades antrópicas. São discutidas as responsabilidades e postura do projetista quanto à questão. Por fim, passa-se a uma avaliação qualitativa quanto ao emprego em projetos das diversas classes de ferramentas de avaliação de desempenho ambiental. Essa análise abrangente oferece referências de caráter conceitual e prático para o desenvolvimento e a consolidação de ferramentas para avaliação ambiental...

A Parametric Model for Operability of Offshore Support Vessels via Configuration-Based Design

Vidal, Hugo Luckmann
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Trabalho de Conclusão de Curso Formato: 136 f.
EN
Relevância na Pesquisa
55.72%
TCC (graduação) - Universidade Federal de Santa Catarina. Campus Joinville. Engenharia Naval.; O propósito das embarcações de apoio offshore (OSV’s) é dar suporte a indústria do petróleo para várias atividades no mar, como abastecimento, manuseio de âncora, reboque e construção. Para a adequada realização de cada operação, a embarcação requer diferentes habilidades à bordo, em que a disponibilidade e capacidade destas habilidades estão diretamente associadas ao nível operacional da embarcação. O principal objetivo deste trabalho é desenvolver um modelo paramétrico de um OSV para levar em conta as habilidades da embarcação e sua conexão com as principais operações que estes tipos de navio podem realizar, classificando os projetos através de um sistema de pontuação de acordo com o desempenho e custo de construção. O modelo consiste em equações paramétricas, baseadas em análises de regressão de embarcações semelhantes e em uma abordagem preliminar baseada na configuração de módulos específicos, como guindastes, acomodação extra e maior propulsão. O modelo levará em conta diferentes contextos no qual o navio irá operar (e.g. Mar do norte, Ártico e Brasil) e será desenvolvido em ferramentas comuns de engenharia...

Evaluation of the in-plane seismic performance of stone masonry walls

Vasconcelos, Graça; Lourenço, Paulo B.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2005 POR
Relevância na Pesquisa
75.68%
Although traditional historic masonry walls can be viewed as unsuitable structures to undergo seismic actions, they, in fact, exist and frequently represent the major structural elements of ancient buildings. Brick unreinforced masonry walls have been widely studied both from experimental and numerical point of view, but scarce experimental information is available for stone masonry walls. Therefore, the present work aims at increasing the insight about the behavior of typical ancient masonry walls under cyclic loading. Besides the strength and stiffness characterization, information about nonlinear deformation capacity is provided in terms of ductility factor and lateral drifts, which represent a step forward for the new concepts of performance based design.

Metodologias inovadoras no cálculo sísmico de estruturas em alvenaria simples e confinada; New methodologies for seismic design of unreinforced and confined masonry structures

Marques, Rui Filipe Pedreira
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Tese de Doutorado
Publicado em 22/02/2013 POR
Relevância na Pesquisa
65.76%
Tese de doutoramento em Engenharia Civil (área de especialização em Estruturas); As construções em alvenaria representam uma parte importante do legado construído e cultural do passado, mas também uma solução sustentável para o futuro. Esta é a principal premissa que motivou este trabalho, assim como o desenvolvimento significativo verificado na indústria de produtos para alvenaria nos últimos anos, apesar do panorama atual em que o material alvenaria é essencialmente usado em paredes de preenchimento das estruturas. Neste trabalho estudam-se as possibilidades de construção e o cálculo moderno de estruturas em alvenaria. É apresentado o estado da arte de procedimentos de cálculo sísmico, os quais derivaram sobretudo da experiência acumulada na observação pós-sismo na ex-Jugoslávia e em Itália. Nestes países verificou-se uma grande preocupação na avaliação sísmica de estruturas existentes e na continuidade da construção com alvenaria estrutural, através da realização de amplos estudos experimentais, do desenvolvimento de ferramentas de simulação analítica, da elaboração de normas para cálculo e da disponibilização de software apelativo. Os procedimentos e ferramentas desenvolvidos para aplicação baseiam-se...

Application of performance based nonlinear static pushover analysis for seismic design of RC buildings

Bhatti, A. Q.; Varum, H.
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
65.72%
Seismic retrofitting of already constructed buildings is one of the most effective methods of decreasing the risk. However the seismic performance of the structure may not be improved by Strengthening unless the professional engineer selects an appropriate modifying technique based on seismic evaluation of the already constructed structures. In this paper nonlinear static pushover analysis has been performed for the said building. The demand spectrum of ATC 40 procedure for this building was compared with real site based demand spectra. The simulation has been compared with and without strengthened structure. The plastic hinges of the building have been plotted for different safety margins.

Performance-based design optimization using uniform deformation theory: a comparison study

Mohammadi,R. Karami; Ghasemof,A.
Fonte: Associação Brasileira de Ciências Mecânicas Publicador: Associação Brasileira de Ciências Mecânicas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 EN
Relevância na Pesquisa
95.81%
The uniform deformation theory (UDT) is a relatively new concept in structural seismic design optimization. However, the results of optimization based on this theory have not yet been compared with other optimization techniques such as metaheuristics, and the optimality of the designs has been proved only by comparing the results with the conventional designs. This paper presents a new algorithm based on the UDT to performance-based design optimization (PBDO) of steel moment frames. In order to verify robustness of this method, the achieved results of PBDO for two baseline steel moment frames are compared with three metaheuristics consisting of genetic algorithm (GA), ant colony optimization (ACO), and particle swarm optimization (PSO). The results indicate that the optimization based on UDT provides a much higher convergence rate to the optimum design compared with metaheuristics.

Design of an impact evaluation using a mixed methods model – an explanatory assessment of the effects of results-based financing mechanisms on maternal healthcare services in Malawi

Brenner, Stephan; Muula, Adamson S; Robyn, Paul Jacob; Bärnighausen, Till; Sarker, Malabika; Mathanga, Don P; Bossert, Thomas; De Allegri, Manuela
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
55.77%
Background: In this article we present a study design to evaluate the causal impact of providing supply-side performance-based financing incentives in combination with a demand-side cash transfer component on equitable access to and quality of maternal and neonatal healthcare services. This intervention is introduced to selected emergency obstetric care facilities and catchment area populations in four districts in Malawi. We here describe and discuss our study protocol with regard to the research aims, the local implementation context, and our rationale for selecting a mixed methods explanatory design with a quasi-experimental quantitative component. Design: The quantitative research component consists of a controlled pre- and post-test design with multiple post-test measurements. This allows us to quantitatively measure ‘equitable access to healthcare services’ at the community level and ‘healthcare quality’ at the health facility level. Guided by a theoretical framework of causal relationships, we determined a number of input, process, and output indicators to evaluate both intended and unintended effects of the intervention. Overall causal impact estimates will result from a difference-in-difference analysis comparing selected indicators across intervention and control facilities/catchment populations over time. To further explain heterogeneity of quantitatively observed effects and to understand the experiential dimensions of financial incentives on clients and providers...

A performance-based approach to retrofitting unreinforced masonry structures for seismic loads; Performance-based approach to retrofitting URM structures for seismic loads

Bouchard, Keith M. (Keith Michael)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 59, [47] leaves
ENG
Relevância na Pesquisa
55.67%
The structural inadequacy of existing unreinforced masonry (URM) buildings to resist possible seismic loading is a serious problem in many parts of the United States, including the Northeast and Midwest. The fact that many of these buildings are deemed historic structures or house critical facilities, like firehouses, emphasizes the need for an effective retrofitting program. The Federal Emergency Management Agency published a performance-based design code - FEMA 356 - in 2000 to use for analyzing and retrofitting existing structures. This code includes procedures for URM buildings. This paper applies these performance-based analysis procedures to a URM shear wall and compares the results to a modified analysis proposed by researchers. The wall is then rehabilitated using two common retrofit methods and again analyzed using the code. Recommendations are made for practicing engineers when evaluating URM structures for seismic loads.; by Keith M. Bouchard.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2007.; Includes bibliographical references (leaves 58-59).

A probabilistic approach to Performance-Based Wind Engineering (PBWE)

PETRINI, FRANCESCO
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
85.85%
Performance-Based Design (PBD) is a modern and efficient framework to conceive and assess complex structural systems, which allow designers to consistently take into account both natural and man-made hazards, both in the design of new facilities and in the rehabilitation or retrofitting of existing ones. The first formal applications of PBD were devoted to seismic engineering and design; later it has been extended to other engineering fields, like Blast Engineering and Fire Engineering. Wind engineering has appeared of great potential interest for further developments of PBD. The expression "Performance-Based Wind Engineering" (PBWE) was introduced for the first time in 2004 by an Italian research project. In this work, the approach proposed by the Pacific Earthquake Engineering Research Center (PEER) for Performance-Based Earth-quake Engineering is extended to the case of PBWE. The general framework of the approach is illustrated and applied to two example cases: a long span suspension bridge and an offshore wind turbine.

Performance-Based Financing Toolkit

Fritsche, György Bèla; Soeters, Robert; Meessen, Bruno
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
EN_US
Relevância na Pesquisa
65.69%
Performance-based financing (PBF) approaches have expanded rapidly in lower-and middle income countries, and especially in Africa. The number of countries has grown from three in 2006 to 32 in 2013. PBF schemes are flourishing and cause considerable demand for technical assistance in executing these health reforms in a rational and accountable manner. Currently there is a lack of knowledge among many health reformers of how to implement performance-based financing pilot projects, and scale them up intelligently. In a context of tremendous demand for solid design and implementation experience and given the rapid expansion of results-based financing (RBF) programs, there is an urgent need to build capacity in designing and implementing PBF programs. As yet there has been little attempt to gather the learning from these experiences together in one volume and, moreover, in a form that serves as a guide to implementers. This toolkit answers the most pressing issues related to the supply-side RBF programs of which PBF forms part.

The Challenge of Reducing Non-Revenue Water in Developing Countries--How the Private Sector Can Help : A Look at Performance-Based Service Contracting

Kingdom, Bill; Liemberger, Roland; Marin, Philippe
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
55.7%
This study explains that one of the major issues affecting water utilities in the developing world is the considerable difference between the amount of water put into the distribution system and the amount of water billed to consumers (also called "non-revenue water" [NRW]). High levels of NRW reflect huge volumes of water being lost through leaks, not being invoiced to customers, or both. It seriously affects the financial viability of water utilities through lost revenues and increased operational costs. In this report, a number of case studies, taken from some of the largest and most recent performance-based NRW contracts, are studied and discussed in terms of their technical and financial performance. Lessons learned from the case studies are analyzed, showing the potential benefits of NRW performance-based service contracting with the private sector. This paper was prepared as part of a Public-Private Infrastructure Advisory Facility (PPIAF)-financed study to investigate opportunities for the use of the private sector to assist water utilities in developing countries in reducing non-revenue water. This study indicates that the private sector help ailing public sector utilities in developing countries reduce NRW even though the performance- based service contracting approach described should not be seen as a substitute for overall sector reform. The case studies...

The Challenges of Performance Based Design in Structural Testing

NEGRO PAOLO; DIMOVA Silvia
Fonte: Nagoya University Publicador: Nagoya University
Tipo: Contributions to Conferences Formato: Printed
ENG
Relevância na Pesquisa
65.88%
There is a widespread consensus about the need of developing design methods based on performance objectives rather than on strict practical rules. The European scientific community can already rely on a suite of norms, the Eurocodes, which explicitly state the fundamental requirements in terms of performance. However, even though built around performance based fundamental requirements, the Eurocodes are still far from allowing for a fully performance based design. The scientific community is currently tackling the definition, harmonization and cross-correlation of standard and new performance parameters, so that requirements could eventually be specified in terms of those parameters, and new design methods could be developed. Meanwhile, prescriptive design rules are maintained and practice and experience, rather than explicitly quantified performance criteria, control the design process. The challenges of Performance Based Design in structural testing are shown with reference to recently performed large-scale pseudodynamic tests at the European Laboratory for Structural Assessment (ELSA). The importance of the selection of the most suitable experimental technique is illustrated. It is shown that the prescriptions of current hazard estimation techniques for the thresholds of the damage states cannot be automatically transferred to RC frame structures designed according to the Eurocodes. To this end...

RISK-BASED DESIGN OF BRIDGES AND ASSOCIATED TRANSPORTATION NETWORKS UNDER NATURAL HAZARDS

Wang, Zhenghua
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
Relevância na Pesquisa
65.95%
The highway infrastructure system in the United States is deteriorating and facing an increased number of threats from natural and man-made hazards, including earthquakes, scour, hurricanes, and vehicle collisions. At the same time, the reliable functioning of the highway system plays an important role in emergency response and recovery processes after disaster strikes. However, there are several inadequacies in current codes and associated practice for the design of bridges, as well as funding restrictions for their upkeep. Although recent changes in the seismic design of bridges have adopted displacement-based design approaches to promote adequate performance under seismic loads, the current design philosophy hinges upon a uniform hazard perspective without explicit consideration of a homogeneous risk of damage or collapse. In addition, this approach does not reflect the influence of individual bridges on the transportation network behaviour, which is desirable to estimate the performance of a transportation infrastructure system and enhance its overall post-event operation. Moreover, current bridge design specifications deal with various extreme hazards independent of one another. The reliable performance of transportation infrastructure systems under natural hazards requires a new life-cycle risk-based design method...

Performance-based design for arson threats: policy analysis of the physical security for federal facilities standard

Neale, Robert A.
Fonte: Monterey California. Naval Postgraduate School Publicador: Monterey California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
65.78%
CHDS State/Local; Although perhaps not so dramatic or newsworthy as chemical, biologic, radiologic, nuclear, or explosive attacks, intentionally set fires are identified security threats to federal buildings accessible to the public. The Department of Homeland Security Interagency Security Committee in 2010 adopted building construction standards that purport to give facility safety committees and building designers guidance on developing permanent countermeasures to 31 diverse threat scenarios described in the Design-Basis Threat. To assess the effectiveness of the permanent countermeasures options provided in the Physical Security Criteria for Federal Facilities, a performance-based approach to evaluating the design and construction features is recommended. Clearly articulated performance objectives and quantifiable characterization of the hazardous elements comprising the threat scenarios are essential to evaluating outcomes using a performance-based design approach. A mixed methods research approach is used to analyze the Physical Security Criteria for Federal Facilities standard to make policy recommendations that may enhance occupant safety and federal property protection from arson attacks. Computerized fire effects modeling is used to compare outcomes in non-military and non-postal federal facilities from a variety of simulated arson scenarios using commonly available accelerants.

Performance-Based Road Rehabilitation and Maintenance Contracts in Argentina : A Review of Fifteen Years of Experience (1996-2010)

Marcela Silva, Maria; Liautaud, Gerard
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
55.68%
The road sector is the dominant mode of transport in Argentina carrying nearly 80 percent of total freight volume. The road network has a total length of about 630,000 km (11 percent paved), divided in three administrative levels: national, provincial, and municipal. However, more than 70 percent of total traffic volumes are concentrated on the paved national and provincial network, with the municipal network consisting of unpaved roads, access roads to farms and feeder roads with very low traffic volumes. A survey carried out in 1992 confirmed that only 44 percent of the national paved network was in good condition, with a high 35 percent of roads in poor condition. Rehabilitation works for the non-concessioned portion were contracted to the private sector under the traditional ad-measurement type or unit price-based system while maintenance activities continued to be carried out by force-account. In 1993 a loan from the World Bank was approved to finance, for the first time, high priority rehabilitation and maintenance works on the non-concessioned paved network...

Performance-Based Contracting in Health : The Experience of Three Projects in Africa

Johannes, Lars; Mullen, Patrick; Okwero, Peter; Schneidman, Miriam
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Brief; Publications & Research
ENGLISH
Relevância na Pesquisa
55.68%
Performance-based contracting in health is an example of a results-based financing approach to improving health service delivery. In 2003 and 2004 the Global Partnership on Output-Based Aid (GPOBA) supported the design of three schemes using performance-based contracting in Uganda, the Democratic Republic of Congo, and Rwanda. GPOBA's technical assistance has led to three innovative projects funded by the World Bank and the Canadian International Development Agency (CIDA). This note reviews early lessons from these schemes.

Displacement Based Design Procedures for RC Bridges - Formulation and Comparison of Two Approaches

AYALA Gustavo; PAULOTTO Carlo; TAUCER FABIO
Fonte: Università di Pisa Publicador: Università di Pisa
Tipo: Contributions to Conferences Formato: CD-ROM
ENG
Relevância na Pesquisa
55.85%
This paper presents the formulation, evaluation and comparison of two newly developed displacement based design procedures for reinforced concrete bridges. The foundations of both methods are established within the framework of the performance based design philosophy, however they are different inasmuch as the first one is an iterative linear method based on the concepts of the substitute structure, proposed more than three decades ago, and the use of seismic demands given by damping reduced design spectra and the other is a direct non-iterative non-linear procedure based on the concepts of a non-linear SDOF reference system and seismic demands given by uniform hazard design spectra for an assumed rate of exceedence of the target performance. To understand the potential of application of both methods, the issue of bridge regularity is explicitly examined showing that, further to the concept that regularity of a bridge is closely related to the expected seismic performance under design actions, it is also linked to the used performance based evaluation/design method. It is shown that when a bridge structure is irregular, both proposed procedures may lead to incorrect evaluations/designs unless some additional considerations are introduced in the procedures. The results obtained from both methods are illustrated by applying them to five bridges.; JRC.G.5-European laboratory for structural assessment

Design of an Impact Evaluation Using a Mixed Methods Model; An Explanatory Assessment of the Effects of Results-Based Financing Mechanisms on Maternal Healthcare Services in Malawi

Brenner, Stephan; Muula, Adamson S.; Robyn, Paul Jacob; Bärnighausen, Till; Sarker, Malabika; Mathanga, Don P.; Bossert, Thomas; De Allegri, Manuela
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Journal Article; Publications & Research :: Journal Article; Publications & Research
EN_US
Relevância na Pesquisa
55.73%
In this article we present a study design to evaluate the causal impact of providing supply-side performance-based financing incentives in combination with a demand-side cash transfer component on equitable access to and quality of maternal and neonatal healthcare services. This intervention is introduced to selected emergency obstetric care facilities and catchment area populations in four districts in Malawi. We here describe and discuss our study protocol with regard to the research aims, the local implementation context, and our rationale for selecting a mixed methods explanatory design with a quasi-experimental quantitative component.

A performance-based optimal structural design methodology

Beck, James L.; Papadimitriou, Costas; Chan, Eduardo; Irfanoglu, Ayhan
Fonte: California Institute of Technology Publicador: California Institute of Technology
Tipo: Report or Paper; PeerReviewed Formato: application/pdf
Publicado em 01/01/1998
Relevância na Pesquisa
55.79%
A general framework for multi-criteria optimal design is presented which is well-suited for performance-based design of structural systems operating in an uncertain dynamic environment. A decision theoretic approach is used which is based on aggregation of preference functions for the multiple, possibly conflicting, design criteria. This allows the designer to trade off these criteria in a controlled manner during the optimization. Reliability-based design criteria are used to maintain user-specified levels of structural safety by properly taking into account the uncertainties in the modeling and seismic loads that a structure may experience during its lifetime. Code-based requirements are also easily incorporated into this optimal design process. The methodology is demonstrated with two simple examples involving the design of a three-story steel-frame building for which the ground motion uncertainty is characterized by a probabilistic response spectrum which is developed from available attenuation formulas and seismic hazard models.