Dissertations / Theses: 'Structural failures'

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De, Stefano Serena. "Structural failures due to lack of bracing." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.

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The goal of the research is to provide an overview of those factors that play a major role in structural failures and also to focus on the importance that bracing has in construction accidents. A temporary bracing system is important to construction safety, yet it is often neglected. Structural collapses often occur due to the insufficient support of loads that are applied at the time of failure. The structural load is usually analyzed by conceiving the whole structure as a completed entity, and there is frequently a lack of design or proper implementation of systems that can provide stability during construction. Often, the specific provisions and requirements of temporary bracing systems are left to the workers on the job site that may not have the qualifications or expertise for proper execution. To effectively see if bracing design should get more attention in codes and standards, failures which could have been avoided with the presence and/or the correct design of a bracing system were searched and selected among a variety of cases existing in the engineering literature. Eleven major cases were found, which span in a time frame of almost 70 years, clearly showing that the topic should get more attention. The case studies are presented in chronological order and in a systematic way. The failed structure is described in its design components and the sequence of failure is reconstructed. Then, the causes and failure mechanism are presented. Advice on how to avoid similar failures from happening again and hypothetic solutions which could have prevented the collapses are identified. The findings shows that insufficient or nonexistent bracing mainly results from human negligence or miscalculation of the load analysis and show that time has come to fully acknowledge that temporary structures should be more accounted for in design and not left to contractors' means and methods of construction.

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Sadowski, Adam Jan. "Modelling of failures in thin-walled metal silos under eccentric discharge." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/8760.

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Eccentric discharge of granular solids is widely considered one of the most serious design conditions for thin-walled metal silos, and one which has been the cause of very many silo disasters in the past. Yet the reasons for these consequences have not been very well understood, given the serious difficulties inherent in measuring or modelling flow patterns of granular solids, wall pressures and the associated structural response. To this end, this thesis presents a programme of theoretical and computational analyses which investigate the effects of a very wide range of different discharge flow patterns from silos, including both concentric and eccentric flows. The critical effects of changes of flow channel geometry, silo aspect ratio, changes of plate thickness and geometric and material nonlinearity are explored in detail. The codified procedures and pressure distributions for concentric and eccentric discharge of the EN 1991-4 (2007) European Standard are analysed first on a number of example silos custom-designed according to EN 1993-1-6 (2007) and EN 1993-4-1 (2007), followed by the development and investigation of a more complete mixed flow pressure theory. The computational analyses presented in this thesis are thought to be the first of their kind.

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Philipps, Joseph Caleb. "Sensor characterization for long-term remote monitoring of bridge piers." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4907.

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Thesis (M.S.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 2, 2008) Includes bibliographical references.

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Taricska, Michael. "An Analysis of Recent Bridge Failures (2000-2012)." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397600086.

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Burrell, Paul A. "Structural errors and failures in construction : is knowledge hidden?" Thesis, Anglia Ruskin University, 2017. http://arro.anglia.ac.uk/703821/.

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Structural errors and failures within construction appear to be not reported to other professionals in the industry. This results in little advancement of knowledge and understanding, with the consequence that similar failings are repeated. For example, in 2016 Construction accounted for 6% of the Gross Domestic Product, of this 7% was lost in disputes. There were, however, 30 fatalities. A study of cases from the author’s Practice, into building defects, errors and failures was undertaken. This identified four areas: the education of chartered structural engineers, legislation, the management of construction projects and business ethics, as contributing to errors and failures. A series of open-ended, semi-structured interviews was also undertaken with senior professionals, including the Judiciary, Professors of Engineering, Global Consultants, and Professional Indemnity Insurers. Research findings revealed that technical knowledge is deliberately withheld due to non-disclosure clauses in mediated settlements, and through the practices of global Professional Indemnity Insurers. A Study of pass rates for chartered membership of the Institution of Structural Engineers showed a decrease despite, an increase of academic requirement. Companies that promote Corporate Social Responsibility credentials, often, however, seek the best commercial deal regarding litigation settlement. Furthermore, companies adopt a Friedman business model, which favours shareholders in preference to a Freeman approach, which recognises the interests of all stakeholders. Quality assurance systems used in other industries are not easily and effectively suited to construction practices. This research concludes there is a sound business case to share knowledge, which would reduce claims, increase profits and save lives. Primary legislation must be changed to compel a free exchange of technical knowledge regarding errors and structural failures. A ‘no blame’ repository needs to be established that should help reduce the adversarial nature of the construction industry. Additionally, the suitability of the academic degree curriculum for structural engineers needs to be reassessed.

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Burrell, Paul A. "Structural errors and failures in construction: is knowledge hidden?" Thesis, Anglia Ruskin University, 2017. https://arro.anglia.ac.uk/id/eprint/703821/1/Burrell_2017.pdf.

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Structural errors and failures within construction appear to be not reported to other professionals in the industry. This results in little advancement of knowledge and understanding, with the consequence that similar failings are repeated. For example, in 2016 Construction accounted for 6% of the Gross Domestic Product, of this 7% was lost in disputes. There were, however, 30 fatalities. A study of cases from the author’s Practice, into building defects, errors and failures was undertaken. This identified four areas: the education of chartered structural engineers, legislation, the management of construction projects and business ethics, as contributing to errors and failures. A series of open-ended, semi-structured interviews was also undertaken with senior professionals, including the Judiciary, Professors of Engineering, Global Consultants, and Professional Indemnity Insurers. Research findings revealed that technical knowledge is deliberately withheld due to non-disclosure clauses in mediated settlements, and through the practices of global Professional Indemnity Insurers. A Study of pass rates for chartered membership of the Institution of Structural Engineers showed a decrease despite, an increase of academic requirement. Companies that promote Corporate Social Responsibility credentials, often, however, seek the best commercial deal regarding litigation settlement. Furthermore, companies adopt a Friedman business model, which favours shareholders in preference to a Freeman approach, which recognises the interests of all stakeholders. Quality assurance systems used in other industries are not easily and effectively suited to construction practices. This research concludes there is a sound business case to share knowledge, which would reduce claims, increase profits and save lives. Primary legislation must be changed to compel a free exchange of technical knowledge regarding errors and structural failures. A ‘no blame’ repository needs to be established that should help reduce the adversarial nature of the construction industry. Additionally, the suitability of the academic degree curriculum for structural engineers needs to be reassessed.

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Hirschfeld, Deidre A. "Failure analysis of notched graphite-epoxy tubes." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08252008-161928/.

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Collett, Aaron Bruce. "A validation study of the Montana State University in-plane loader." Thesis, Montana State University, 2006. http://etd.lib.montana.edu/etd/2006/collett/CollettA0806.pdf.

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9

Masterson, Mary Kathryn Washer Glenn A. "Long-term sensing system for bridge piers." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6528.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on November 19, 2009). Thesis advisor: Dr. Glenn Washer. Includes bibliographical references.

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KJERENGTROEN, LIDVIN. "RELIABILITY ANALYSIS OF SERIES STRUCTURAL SYSTEMS (PROBABILITY, DESIGN, FATIGUE)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187909.

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Reliability analysis of series structural systems with emphasis on problems typical for metal fatigue is addressed. Specific goals include the following: (1) Given the distribution of strength of the components and the distribution of external loads on the system what is the probability of failure of the system? (2) Given the target safety index for the system, what would be the target safety index for the components? Exact solutions in the analysis of series structural systems only exists for some special problems. Some of these special problems are investigated. In particular some special cases of the problem of unequal element reliabilities are considered and some interesting observations are made. Numerical integration is in general required even when an exact solution exists. A correction or adjustment factor is developed for an important class of problems. This factor makes it possible to relate element and system probabilities of failure without numerical integration. However in most cases no exact solution to the structural series system problem exists. Approximations by for instance bounds on the probability of failure or Monte Carlo simulation has been the only way of approximating solutions. These two methods are generally not good approximation schemes since they are either too crude or too expensive. In this dissertation an approximation scheme for analysis of series systems where no exact solution exists is developed. The method only requires a simple numerical integration if the component safety index and the correlation coefficient between failure modes is known. Numerous examples are used to verify the method against known exact results and excellent estimates are obtained. Applications by practical examples is also given. In the appendix the problem of convergence of fatigue life distribution is also summarized.

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Zitrou, Athena. "Exploring a Bayesian approach for structural modelling of common cause failures." Thesis, University of Strathclyde, 2006. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27541.

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Common Cause Failures (CCFs) are a class of dependent failures that occur to complex technological systems, such as nuclear power plants, where redundant components serve as multiple layers of defence. For the purposes of quantitative assessment of CCFs, parametric models are used. A common feature of all parametric models is the difficulty in parameter estimation due to limited available observational data. The Unified Partial Method (UPM) for CCF modelling is a systematic methodology that takes into consideration physical and operational system defences. This research explores the application of the Influence Diagram (ID) formalism in order to extend UPM, through an example of Emergency Diesel Generators from nuclear power plants. The proposed model incorporates intermediate stages in the modelling process, namely root causes and coupling factors, to allow for a representation of the CCF mechanisms. Moreover, it captures interactions existing amongst the system's defences, in their contribution to risk. With an underlying Bayesian approach to risk, the model quantifies operational experience, accounts for the epistemic uncertainty, and allows for a coherent combination of expert opinion with observations. This thesis proposes a model structure, which integrates with the ICDE generic database for CCFs. Finally, the ID formalism allows for the propagation of uncertainty within the model structure, and provides a tool for decision-making. The construction of the ID model has been entirely based on expert judgment: the model network has been constructed with the help of experts, whilst a suggested model quantification methodology has been explored. This thesis documents the building process, and explores the behaviour of the resulting model. Findings within this research suggest the feasibility of the proposed methodology for development of a CCF model with a structural and exploratory character.

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Shaikhutdinov, Rustem V. "Structural damage evaluation : theory and applications to earthquake engineering /." Pasadena : California Institute of Technology, Earthquake Engineering Research Laboratory, 2004. http://caltecheerl.library.caltech.edu.

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Bland, Kenneth Edward. "Behavior of Wood Exposed to Fire: A Review and Expert Judgement Procedure for Predicting Assembly Failure." Digital WPI, 2005. https://digitalcommons.wpi.edu/etd-theses/1160.

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This paper summarizes research on the structural perfomance of wood elements and assemblies exposed to fire and reviews methodologies available to predict performance. This reasecrh provides a wealth of information on topics such as how fast a flame spreads across the surface of wood, how much smoke is produced during combustion and at what rate does wood char and at what heat release rate.

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Kenik, Douglas J. "Advanced techniques for constituent-based progressive failure analysis of composite structures." Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1939245921&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Littles, Jerrol W. Jr. "Scattering of longitudinal elastic waves from a distribution of cracks." Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/19242.

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Kurra, Sri Harsha. "Nondestructive testing for finding out the displacement of crack in silicon nitride." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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Grobaski, Thomas C. "Preliminary research for the development of a hot forging die life prediction model." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1102695461.

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Lott, Dennis A. "Analysis of in-flight structural failures of P-3C wing leading edge segments." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23530.

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Jin, Si. "Structural damage detection using higher-order finite elements and a scanning laser vibrometer /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9974641.

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20

Jara, Heiner Lopez, Brandon Bravo Barrionuevo, and Carlos Fernández Díaz. "Application of glass and fan shells to a clay soil to increase its mechanical properties." IOP Publishing Ltd, 2021. http://hdl.handle.net/10757/655956.

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Improving the mechanical properties of a clayey soil is one of the best options to avoid future structural failures in buildings and is cheaper than replacing all the material. Therefore, this article proposes the use of recycled glass and fan shells as reinforcement materials. This article presents an experimental study to evaluate the mechanical properties of a pure and mixed soil. The clay soil was mixed with 7% of glass (PV) and with 3%, 6%, 10%, 12% and 15% of Fan Shells (PCA) duly crushed and passed through sieve #100. Tests of sieve granulometry, sedimentation granulometry, Atterberg limits, modified proctor and drained consolidated direct cut were performed. This allowed comparing all the data obtained and defining the optimal percentage of the mixture in which the clay improves its mechanical properties. According to the tests carried out, the proportion that has 7% glass and 6% Fan Shells has better results because there is an improvement in its dry density from 1,784 g / cm3 to 1,847 g / cm3, its moisture content increases from 9.4% to 12.1%. In addition, its friction angle improves from 28.9 °to 32 °and cohesion from 0.05 kg / cm2 to 0.1 kg / cm2. These results verify that the properties of the clay soil are improved.

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Nacewicz, Rebecca Marie. "Investigation of fire impact on structural steel through case studies." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050406-105306/.

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Turkington, Iain. "Review of the Lai Ping Road slope failures and the influence of the local structural geology." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B30431414.

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Sanchez, Juan Carlos. "Seismic Rehabilitation of Steel Moment Frames Vulnerable to Soft-Story Failures Through Implementation of Rocking Cores." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1029.

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During seismic events, inefficient steel moment frame building systems may exhibit soft-story failures. This thesis focuses on development and validation of a seismic retrofit strategy for avoiding soft-story failures in low-rise and mid-rise steel moment frame buildings. The considered retrofit strategy consists of a sufficiently stiff Rocking Core (RC) pinned to the foundation and pin connected to the existing frame. For demonstration purposes, two representative benchmark steel moment frames, which are modified from the three- and nine-story pre-Northridge steel moment frames designed for Los Angeles in the SAC Steel Project, are considered. Finite Element (FE) models of the benchmark buildings are developed with consideration of member yielding, connection rupture, and P-Delta effect, and validated using published results. Eigenvalue analyses are conducted to investigate the effect of the RC on system modal properties. It is found that in general the added RC with practical stiffness value does not significantly change the fundamental period and therefore does not attract excessive earthquake force to the system. In addition, nonlinear static pushover analyses are performed to address the beneficial contribution of the RC to the system under the performance objectives including immediate occupancy, life safety, and collapse prevention. The Monte-Carlo simulation technique is used to generate the random lateral force distribution required in the nonlinear static pushover analysis. It is found that RC works as expected in all considered scenarios and creates more uniform inter-story distribution along the vertical direction when it is sufficiently stiff. Furthermore, nonlinear dynamic analyses are conducted using three different ground motion suites (including two suites with ground motions having probabilities of exceedance of 2% and 10% in 50 years, and one suite with near-fault ground motions). It is shown that the systems with properly selected RC can achieve the Best Safety Objective defined in FEMA 356 and exhibit collapse prevention performance under near-fault earthquakes.

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Pertsch, Alexander Thomas. "An intelligent stand-alone ultrasonic device for monitoring local damage growth in civil structures." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31716.

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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Jacobs, Laurence J.; Committee Co-Chair: Wang, Yang; Committee Member: Kim, Jin-Yeon. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Singh-Levett, Ishan. "Real-time integral based structural health monitoring." Thesis, University of Canterbury. Mechanical Engineering, 2006. http://hdl.handle.net/10092/1171.

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Structural Health Monitoring (SHM) is a means of identifying damage from the structural response to environmental loads. Real-time SHM offers rapid assessment of structural safety by owners and civil defense authorities enabling more optimal response to major events. This research presents an real-time, convex, integral-based SHM methods for seismic events that use only acceleration measurements and infrequently measured displacements, and a non-linear baseline model including hysteretic dynamics and permanent deformation. The method thus identifies time-varying pre-yield and post-yield stiffness, elastic and plastic components of displacement and final residual displacement. For a linear baseline model it identifies only timevarying stiffness. Thus, the algorithm identifies all key measures of structural damage affecting the immediate safety or use of the structure, and the long-term cost of repair and retrofit. The algorithm is tested with simulated and measured El Centro earthquake response data from a four storey non-linear steel frame structure and simulated data from a two storey non-linear hybrid rocking structure. The steel frame and rocking structures exhibit contrasting dynamic response and are thus used to highlight the impact of baseline model selection in SHM. In simulation, the algorithm identifies stiffness to within 3.5% with 90% confidence, and permanent displacement to within 7.5% with 90% confidence. Using measured data for the frame structure, the algorithm identifies final residual deformation to within 1.5% and identifies realistic stiffness values in comparison to values predicted from pushover analysis. For the rocking structure, the algorithm accurately identifies the different regimes of motion and linear stiffness comparable to estimates from previous research. Overall, the method is seen to be accurate, effective and realtime capable, with the non-linear baseline model more accurately identifying damage in both of the disparate structures examined.

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Singh, Mukti Nath. "Efficient reliability estimation approach for analysis and optimization of composite structures." Master's thesis, Mississippi State : Mississippi State University, 2002. http://library.msstate.edu/etd/show.asp?etd=etd-11072002-103328.

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Hera, Adriana. "Instantaneous modal parameters and their applications to structural health monitoring." Link to electronic dissertation, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-121905-163738/.

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Dissertation (Ph.D..) -- Worcester Polytechnic Institute.
Keywords: structural health monitoring; wavelet transform; time varying vibration modes; instantaneous modal parameters. Includes bibliographical references (p.181-186).

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Arritt, Daniel L. "Lateral collapse potential of wood pallets." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/90905.

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Lateral collapse is a failure mode of wood pallets which most frequently occurs during transportation and handling. The study objective was to develop a simplified procedure for making relative comparisons in the lateral collapse potential of competing pallet designs. A theoretical model was developed to predict the maximum horizontal force a pallet can sustain. A simple equilibrium of forces approach including joint rigidity was used. A lateral load test machine was built which induces and measures the amount of horizontal force required to collapse a pallet. After testing, the model was shown to be accurate when no upper deckboard bending occurred and inaccurate when bending occurred. To account for bending, two multiple regression equations were developed to predict modification factors using a matrix structural analysis program. predicts K-factors for two stringer A closed form solution designs. These K-factors are used to modify the resisting moments generated by the fastened joints. The modified model was shown to slightly overpredict maximum collapse load but did accurately discern differences in relative lateral collapse potential. The ratio of the maximum horizontal load to the vertical load on the pallet provides a means of ranking the potential for lateral collapse. Those designs whose ratios fall between 0.0 and 0.6 are at high risk, from 0.6 but less then 1.0 are at medium risk, and from 1.0 to infinity are at low risk of lateral collapse. These ratios have been calibrated against documented cases of lateral collapse. The factors that influence the lateral collapse potential of a design are stringer aspect ratio, joint characteristics, unit load, and upper deck flexural rigidity.
M.S.

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Tahmasebinia, Faham. "Numerical modelling of reinforced concrete slabs subject to impact loading." Access electronically, 2008. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080716.152001/index.html.

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Mugume, Seith Ncwanga. "Modelling and resilience-based evaluation of urban drainage and flood management systems for future cities." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18870.

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In future cities, urban drainage and flood management systems should be designed not only to reliable during normal operating conditions but also to be resilient to exceptional threats that lead to catastrophic failure impacts and consequences. Resilience can potentially be built into urban drainage systems by implementing a range of strategies, for example by embedding redundancy and flexibility in system design or rehabilitation to increase their ability to efficiently maintain acceptable customer flood protection service levels during and after occurrence of failure or through installation of equipment that enhances customer preparedness for extreme events or service disruptions. However, operationalisation of resilience in urban flood management is still constrained by lack of suitable quantitative evaluation methods. Existing hydraulic reliability-based approaches tend to focus on quantifying functional failure caused by extreme rainfall or increases in dry weather flows that lead to hydraulic overloading of the system. Such approaches take a narrow view of functional resilience and fail to explore the full system failure scenario space due to exclusion of internal system failures such as equipment malfunction, sewer (link) collapse and blockage that also contribute significantly to urban flooding. In this research, a new analytical approach based on Global Resilience Analysis (GRA) is investigated and applied to systematically evaluate the performance of an urban drainage system (UDS) when subjected to a wide range of both functional and structural failure scenarios resulting from extreme rainfall and pseudo random cumulative link failure respectively. Failure envelopes, which represent the resulting loss of system functionality (impacts) are determined by computing the upper and lower limits of the simulation results for total flood volume (failure magnitude) and average flood duration (failure duration) at each considered failure level. A new resilience index is developed and applied to link resulting loss of functionality magnitude and duration to system residual functionality (head room) at each considered failure level. With this approach, resilience has been tested and characterized for a synthetic UDS and for an existing UDS in Kampala city, Uganda. In addition, the approach has been applied to quantify the impact of interventions (adaptation strategies) on enhancement of global UDS resilience to flooding. The developed GRA method provides a systematic and computationally efficient approach that enables evaluation of whole system resilience, where resilience concerns ‘beyond failure’ magnitude and duration, without prior knowledge of threat occurrence probabilities. The study results obtained by applying the developed method to the case studies suggest that by embedding the cost of failure in resilience-based evaluation, adaptation strategies which enhance system flexibility properties such as distributed storage and improved asset management are more cost-effective over the service life of UDSs.

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Bonanni, David L. "Local buckling and crippling of composite stiffener sections." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80050.

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The local buckling, postbuckling, and crippling (failure) of channel, zee, and I- and J-section stiffeners made of AS4/3502 graphite-epoxy unidirectional tape are studied by experiment and analysis. Thirty-six specimens were loaded in axial compression as intermediate length columns. Examination of the experimental results indicates the existence of a number of damage initiation modes, all of which involve either delamination in some part of the specimen or local material strength failure in a comer of the specimen. The ratio of the flange width to thickness has a strong influence on the buckling stress and damage initiation mode. The inner corner radius strongly affects the buckling and crippling stresses for the I- and J-section specimens. Comparison of the numerical results from a computer code for shell analysis (STAGS) with experimental data shows good correlation prior to buckling and at the buckling load, but diminished agreement in the postbuckling region. This lack of postbuckling correlation is attributed to the neglecting of transverse shearing deformations in the structural theory, inaccuracies in the modeling of in-plane boundary conditions, and damage initiation in the experimental specimens. A plane stress failure analysis for five of the specimens shows the compressive fiber mode criterion of Hashin correlates reasonably well with the first detectable damage event. Equilibrium is used to develop interlaminar stress equations for classical laminated plate theory that require high order derivatives of the displacements. Derivatives computed from discrete displacement data using the Discrete Fourier Transform are inaccurate due to the Gibbs phenomenon.
Master of Science

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32

Pant, Sudeep Raj. "Mathematical and physical modelling of crack growth near free boundaries in compression." University of Western Australia. School of Civil and Resource Engineering, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0139.

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[Truncated abstract] The fracture of brittle materials in uniaxial compression is a complex process with the development of cracks generated from initial defects. The fracture mechanism and pattern of crack growth can be altered considerably by the presence of a free surface. In proximity of a free surface, initially stable cracks that require an increase in the load to maintain the crack growth can become unstable such that the crack growth maintains itself without requiring further increase in the load. This leads to a sudden relief of accumulated energy and, in some cases, to catastrophic failures. In the cases of rock and rock mass fracturing, this mechanism manifests itself as skin rockbursts and borehole breakouts or as various non-catastrophic forms of failure, e.g. spalling. Hence, the study of crack-boundary interaction is important in further understanding of such failures especially for the purpose of applications to resource engineering. Two major factors control the effect of the free boundary: the distance from the crack and the boundary shape. Both these factors as well as the effect of the initial defect and the material structure are investigated in this thesis. Three types of boundary shapes - rectilinear, convex and concave - are considered. Two types of initial defects - a circular pore and inclined shear cracks are investigated in homogeneous casting resin, microheterogeneous cement mixes and specially fabricated granulate material. The preexisting defects are artificially introduced in the physical model by the method of inclusion and are found to successfully replicate the feature of pre-existing defects in terms of load-deformation response to the applied external load. It is observed that the possibility of crack growth and the onset of unstable crack growth are affected by the type of initial defect, inclination of the initial crack, the boundary shape and the location of the initial defect with respect to the boundary. The initial defects are located at either the centre or edge of the sample. The stresses required for the wing crack initiation and the onset of unstable crack growth is highest for the initial cracks inclined at 35° to the compression axis, lowest at 45° and subsequently increases towards 60° for all the boundary shapes and crack locations. In the case of convex boundary, the stress of wing crack initiation and the stress of unstable crack growth are lower than for the case of rectilinear and concave boundary for all the crack inclinations and crack locations. The crack growth from a pre-existing crack in a sample with concave boundary is stable, requiring stress increase for each increment of crack growth. The stress of unstable crack growth for the crack situated at the edge of the boundary is lower than the crack located at the centre of the sample for all the crack inclinations and boundary shapes.

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Seon, Guillaume. "Finite element-based failure models for carbon/epoxy tape composites." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28117.

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Peng, Daren 1957. "Methods for failure assessment of structures and applications to shape optimisation." Monash University, Dept. of Mechanical Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/7682.

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35

Pouliot, William. "Two applications of U-Statistic type processes to detecting failures in risk models and structural breaks in linear regression models." Thesis, City University London, 2010. http://openaccess.city.ac.uk/1166/.

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This dissertation is concerned with detecting failures in Risk Models and in detecting structural breaks in linear regression models. By applying Theorem 2.1 of Szyszkowicz on U-statistic type process, a number of weak convergence results regarding three weighted partial sum processes are established. It is shown that these partial sum processes share certain invariance properties; estimation risk does not affect their weak convergence results and they are also robust to asymmetries in the error process in linear regression models. There is also an application of the methods developed here to a four factor Capital Asset Pricing model where it is shown via the methods developed in Chapter 3 that manager stock selection abilities vary over time.

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Ahmed, Sheikh Saad. "Development of Innovative Load Transfer Mechanism to Reduce Hurricane-Induced Failures in New and Existing Residential Construction." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/157.

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Implicit in current design practice of minimum uplift capacity, is the assumption that the connection's capacity is proportional to the number of fasteners per connection joint. This assumption may overestimate the capacity of joints by a factor of two or more and maybe the cause of connection failures in extreme wind events. The current research serves to modify the current practice by proposing a realistic relationship between the number of fasteners and the capacity of the joint. The research is also aimed at further development of non-intrusive continuous load path (CLP) connection system using Glass Fiber Reinforced Polymer (GFRP) and epoxy. Suitable designs were developed for stud to top plate and gable end connections and tests were performed to evaluate the ultimate load, creep and fatigue behavior. The objective was to determine the performance of the connections under simulated sustained hurricane conditions. The performance of the new connections was satisfactory.

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Hafner, Ferdinand. "Cognitive biases and structural failures in United States foreign policy explaining decision-making dissonance in Phase IV policy and plans for Iraq." Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Dec%5FHafner.pdf.

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Thesis (M.A. in National Security Affairs)--Naval Postgraduate School, December 2007.
Thesis Advisor(s): Russell, James. "December 2007." Description based on title screen as viewed on January 18, 2008. Includes bibliographical references (p. 63-71). Also available in print.

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Cucchi, Andrea. "Changes in codes, standards, practices following building structural failures and limit states steel design comparison: AISC 13th ed vs. Eurocode 3 (2005)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2333/.

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Menchel, Kfir. "Progressive collapse: comparison of main standards, formulation and validation of new computational procedures." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210452.

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Throughout recent history, famous records of building failures may be found, unfortunately accompanied by great human loss and major economic consequences. One of the mechanisms of failure is referred to as ‘progressive collapse’: one or several structural members suddenly fail, whatever the cause (accident or attack). The building then collapses progressively, every load redistribution causing the failure of other structural elements, until the complete failure of the building or of a major part of it. The civil engineering community’s attention to this type of event was first drawn by the progressive collapse of the building called Ronan Point, following a gas explosion in one of the last floors. Different simplified procedures for simulating the effects of progressive collapse can now be found in the literature, some of them described in detail. However, no extensive study can be found, in which these procedures are compared to more complete approaches for progressive collapse simulation, aiming at the comparison of the assumptions underlying them. To further contribute to the elaboration of design codes for progressive collapse, such a study would therefore be of great interest for practitioners.

All parties involved with the subject of progressive collapse are currently attempting to bridge the gap between the work done on the research front on the one hand, what can be considered as a fitting numerical model for regular industrial use on the other, and finally, the normalisation committees. The present research work aims at providing insight as to how the gaps between these poles may be reduced. The approach consists in studying the various hypotheses one by one, and gradually adding complexities to the numerical model, if they prove to be warranted by the need for sufficient accuracy. One of the contributions of the present work stems from this approach, in that it provides insight regarding the validity of the various simplifying assumptions. It also leads to the development of procedures which are kept as simple as possible, in an attempt to design them as best as possible for regular industrial use.

The objective of simplifying assumptions validation is pursued in Chapter 2. This chapter consists of the text of a paper entitled “Comparison and study of different progressive collapse simulation techniques for RC structures”, in which the main simplifying assumptions of the progressive collapse guidelines are detailed and assessed. The DoD [1] and GSA [2] static linear and non-linear procedures are investigated, and compared to more complete approaches in order to assess their validity.

In the next two chapters, two new procedures for design against progressive collapse are developed. They are based on quasi-static computations, their main objective being to account accurately for dynamic inertial effects. The first of these chapters consists in the text of a paper entitled “A new pushover analysis procedure for structural progressive collapse based on a kinetic energy criterion”, in which energetic considerations allow for the development of a static equivalent pushover procedure. The second chapter consists of the text of a paper entitled “A new pushover analysis procedure for structural progressive collapse based on optimised load amplification factors”, which uses load amplification factors resulting from optimisation procedures in order to account for dynamic inertial effects. The contributions of these two papers lie in the fact that they offer an improved accuracy on the results, when compared with other procedure available in the literature, which follow the same general principles. The two proposed procedures are thoroughly validated by systematic comparisons with results obtained with the more costly dynamic non-linear computations.

Finally, an additional chapter focuses on the various approaches that can be adopted for the simulation of reinforced concrete beams and columns. Because a rather simple model for reinforced concrete is used in Chapter 2, the bulk of this chapter consists in the implementation of a more complex fibre-based non-linear beam element. Comparisons performed with this model provide insight to the limitations of the simpler model, which is based on the use of lumped plastic hinges, but show this simpler model to be valid for the purposes of the present work.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Chies, Josué Argenta. "Ensaios não destrutivos em concreto : detecção de falhas no interior de estruturas de concreto com o uso de ultrassom." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/127927.

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A aplicação de Ensaios Não Destrutivos (END) é considerada uma alternativa para monitorar o estado das estruturas de concreto armado, principalmente quando ocorrem falhas de projeto, erros de dosagem, problemas na mistura, transporte ou lançamento do concreto. A medida da Velocidade de Pulso Ultrassônico (VPU) é um END que vem sendo usado comumente em diversas áreas da engenharia civil, devido à facilidade da operação, ao seu baixo custo, à rapidez na execução dos testes e à ausência de danos ao material analisado. O objetivo deste trabalho consiste em apresentar o resultado de uma pesquisa experimental, que visou estudar a influência que determinadas variáveis operacionais exercem sobre os resultados obtidos nos ensaios de VPU e qual a real capacidade de penetração e detecção de defeitos de diversas magnitudes. As medições foram realizadas utilizando o ultrassom pelo modo de transmissão indireta, pois esta é a alternativa que mais se adapta às condições verificadas no exame de estruturas reais de concreto armado. Primeiramente, foram moldados em laboratório dois blocos de concreto, com dimensões próximas às encontradas em estruturas reais de grande porte: um com armadura nas duas faces e outro sem armadura. Em ambos os elementos foram introduzidos objetos para simular possíveis falhas de concretagem. Em uma segunda etapa, foram realizadas perfurações visando identificar a capacidade de detecção de vazios da técnica de VPU para diferentes profundidades. Os resultados são apresentados na forma de imagens geradas através de software e por meio de analises estatísticas. Este estudo verificou que a escolha dos parâmetros de ensaio é um fator determinante para permitir a interpretação correta dos resultados, salientando-se que a experiência do operador e as dimensões de grid são os parâmetros que mais interferem na interpretação dos dados.
The use of Non-destructive Testing (NDT) methods is considered an alternative to monitor the behaviour of reinforced concrete structures, especially when there are design problems or errors related to concrete mixing, transport, placement and casting errors. The Ultrasonic Pulse Velocity (UPV) method is a Non-Destructive Test that is gaining acceptance. The test has been commonly used in various civil engineering areas due to the fact that it is easy to operate and rapid to perform, and to the low cost and lack of damage to the tested material. The objective of this work is to present the results of an experimental research that aimed to study the influence of certain technological variables on the measurements obtained from UPV tests. The work also aims to gather data to assess the penetration capacity of the US waves and their ability to detect defects of various dimensions. The measurements were performed using the indirect transmission mode, to simulate real work conditions on large structures. Firstly, two massive concrete blocks were cast in the laboratory, with dimensions close to real life structures: one with steel reinforcement on both sides and the other without reinforcement. Objects were introduced in both elements to simulate possible defects due to casting. In a second stage, perforations were conducted in the concrete elements to identify the void detection capability of the UPV technique for different depths. The results are presented by images generated by specific software and by using statistical analysis. This study found that the test parameters influence significantly the correct interpretation of the results. The operator experience and the grid dimensions are the parameters that most influence UPV data analysis.

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Mélo, Mauro José Araújo Campelo de. "Análise de laudos emitidos sobre "prédios tipo caixão" da região metropolitana de Recife : causas apontadas para os desabamentos e interdições." Universidade Católica de Pernambuco, 2007. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=177.

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Nos últimos 20 anos, alguns municípios da Região Metropolitana do Recife - PE, têm sido afetados por problemas diversos em obras de Engenharia Civil, contabilizando, inclusive, óbitos. O mais grave desses problemas, dado ao número de edificações envolvidas, diz respeito aos prédios tipo caixão; alguns ruíram e vários foram e estão interditados e houve desinterdição. O objetivo geral da presente dissertação é analisar os laudos técnicos produzidos sobre os prédios tipo caixão, construídos nos Municípios de Olinda, Jaboatão dos Guararapes e Paulista - PE, tendo como meta estudar as causas apontadas para os desabamentos e interdições das referidas edificações. De um modo geral, pode-se apontar como causas dos desabamentos, as seguintes: falhas ou insuficiência de projeto (31,4%); baixa qualidade ou inadequação dos materiais (17,1%); falhas ou vícios de construção (34,4%); causas ambientais (17,1%). Já para as interdições: falhas ou insuficiência de projeto (21,4%); baixa qualidade ou inadequação dos materiais (3,5%); falhas ou vícios de construção (2,8%); uso inadequado ou falta de manutenção (26,0%); causas ambientais (4,3%); outras causas (42,0%). As desinterdições ocorreram quando foram atendidas as restrições feitas pela Defesa Civil de cada município, e que envolviam problemas estruturais e de habitabilidade. Constata-se também uma atuação inadequada dos órgãos de fiscalização e a ausência de padronização dos laudos e de um modelo técnico para a recuperação adequada dessas construções. Espera-se ter contribuído, através da análise e sistematização dos dados contidos nos laudos estudados, para trabalhos futuros, visando o desenvolvimento de tecnologia capaz de equacionar a situação dos referidos imóveis
In the past 20 years, some cities of the Metropolitan Area of Recife - PE, have been affected by several problems in Civil Engineering constructions, some of which resulted in human deaths. The most serious of these problems, given the number of constructions involved, concerns the specific building called box; some of the buildings did fall and several others have been interdicted. Just a few of them were cleared and the majority of them continue to be interdicted. The general objective of the present dissertation is to analyze the awards produced on the building type box, built in the cities of Olinda, Jaboatão dos Guararapes and Paulista. Its goal is to study the causes pointed out as responsible for the collapse and interdictions of those constructions. In a general way, it can be pointed out as causes of the collapses, the following ones: imperfections or insufficiency of project (31.4%); low quality or inadequacies of the materials (17.1%); construction mistakes (34.4%); environmental causes (17.1%). For the interdictions: imperfections or insufficiencies of project (21.4%); low quality or inadequacies of the materials (3.5%); construction mistakes (2.8%); inadequate use or lack of maintenance (26.0%); environmental causes (4.3%); other causes (42.0%). The buildings were cleared when the conditions made by the Civil Defense of each city were met; they involved structural problems and habitability. Its also evident an inadequate performance of the inspection agencies and the lack of standardization of the awards, as well as the absence of a model for the adequate recovery of these constructions. One expects to have contributed, through the analysis and systematization of the data contained in the studied awards, for future works, aiming at the development of technology capable to equate the situation of the cited real estates.

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Barke, Derek Woolrich 1975. "An in situ test for stress corrosion damage and tension in bolts." Monash University, Dept. of Mechanical Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/7686.

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Lemos, Sérgio Pereira Pinto. "Avaliação do grau do dano das estruturas do subsolo de três edifícios situados na Região Metropolitana do Recife." Universidade Católica de Pernambuco, 2006. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=29.

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Procurando conhecer o grau de deterioração precoce das estruturas de concreto armado dos edifícios residenciais da Região Metropolitana da Cidade do Recife, Estado de Pernambuco, este trabalho visa, utilizando um método de quantificação dos danos e o uso de ensaios, avaliar as patologias das estruturas estudadas. Estudou-se três edifícios residenciais (ER), com semelhante padrão de construção, idades construtivas aproximadas e inseridos em diferentes classes de agressividade ambiental. Foi realizada inspeção visual e ensaios em amostras dos pilares, vigas, lajes e reservatório inferior do subsolo dos três edifícios. Após análise dos três edifícios, verificou-se que o caso ER 1, localizado em classe ambiental de agressividade forte (III), a mais agredida pelo meio ambiente, e o estudo de caso ER 2, localizado a uma distância significativa da orla marinha em Classe de Agressividade Ambiental II, apresentaram grau de deterioração media (GD) de 36,98 e 31,23 respectivamente, com recomendação para inspeção periódica e intervenção a médio prazo. Já o estudo de caso ER 3, que está localizado dentro da uma classe de agressividade forte (III), em orla marinha, porém com barreiras de proteção que evitam a incidência direta da névoa salina, encontra-se com alto grau de deterioração (GD = 103,94), sugerindo uma intervenção imediata com riscos de colapso
This work aims to evaluate the pathology of residential buildings structures located at the Metropolitan Region of Recife, Brazil using the quantification of damages to measure the degree of early deterioration of reinforced concrete. Three residential buildings (RB) with similar construction standards were studied. All buildings have approximate age and are inserted into environmental aggressiveness distinct. A visual inspection took place as well as a laboratorial sample analysis of their pillars, beams and underground water reservatories. It was verified that the RB1 case, located at a high environmental aggressiveness class (III), and the RB2 case, located significatively far from the sea and classified with a moderate environmental aggressiveness class (II), both presented a medium degree of deterioration (GDE). For both buildings it is suggested a periodic inspection recommendation and a medium term intervention (GD 1 = 36,98 ; GD 2 = 31,23). The third case (RB3), located at a high environmental aggressiveness class (III) and seafront with protection barriers, presented a high degree of deterioration (GD 3=103,94). It is suggested for RB3 an immediate intervention with collapse risks

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Allen, Christine. "Role of end peeling in behavior of reinforced concrete beams with externally bonded reinforcement." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33982.

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Aging bridges in the United States demand effective, efficient, and economical strengthening techniques to meet future traffic requirements. One such technique is to bond steel or fiber reinforced polymer (FRP) plates to the tension faces of reinforced concrete bridge beams with adhesives to strengthen them in flexure. However, beams that have been flexurally strengthened in this manner often fail prematurely, in particular by plate end peeling. The benefits of flexural strengthening by externally bonded reinforcement can only be fully realized by preventing premature failure modes so as to allow the development of composite action between the beam and the external reinforcement. With this goal in mind, several critical limit states of externally reinforced beams are examined in this thesis. Models developed by Roberts (1989) and by Colotti, Spadea, and Swamy (2004) that predict premature plate end debonding are examined in depth using data from previously conducted experimental programs that employed both steel and FRP external reinforcement. In addition, various parameters of the concrete beam, adhesive, and external reinforcement are analyzed in each model to determine the role of each parameter in failure prediction. A critical appraisal of the performance of the models using existing experimental data leads to the selection of the Roberts (1989) model. This model is used to develop recommended design guidelines for flexurally strengthening reinforced concrete bridge beams with externally bonded FRP plates and for preventing premature plate peeling.

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Lea, Patrick D. "Fluid Structure Interaction with Applications in Structural Failure." Thesis, Northwestern University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3605735.

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Methods for modeling structural failure with applications for fluid structure interaction (FSI) are developed in this work. Fracture as structural failure is modeled in this work by both the extended finite element method (XFEM) and element deletion. Both of these methods are used in simulations coupled with fluids modeled by computational fluid dynamics (CFD). The methods presented here allow the fluid to pass through the fractured areas of the structure without any prior knowledge of where fracture will occur. Fracture modeled by XFEM is compared to an experimental result as well as a test problem for two phase coupling. The element deletion results are compared with an XFEM test problem, showing the differences and similarities between the two methods.

A new method for modeling fracture is also proposed in this work. The new method combines XFEM and element deletion to provide a robust implementation of fracture modeling. This method integrates well into legacy codes that currently have element deletion functionality. The implementation allows for application by a wide variety of users that are familiar with element deletion in current analysis tools. The combined method can also be used in conjunction with the work done on fracture coupled with fluids, discussed in this work.

Structural failure via buckling is also examined in an FSI framework. A new algorithm is produced to allow for structural subcycling during the collapse of a pipe subjected to a hydrostatic load. The responses of both the structure and the fluid are compared to a non-subcycling case to determine the accuracy of the new algorithm.

Overall this work looks at multiple forms of structural failure induced by fluids modeled by CFD. The work extends what is currently possible in FSI simulations.

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Mercatoris, Benoît. "Multi-scale modelling of shell failure for periodic quasi-brittle materials." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210194.

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In a context of restoration of historical masonry structures, it is crucial to properly estimate the residual strength and the potential structural failure modes in order to assess the safety of buildings. Due to its mesostructure and the quasi-brittle nature of its constituents, masonry presents preferential damage orientations, strongly localised failure modes and damage-induced anisotropy, which are complex to incorporate in structural computations. Furthermore, masonry structures are generally subjected to complex loading processes including both in-plane and out-of-plane loads which considerably influence the potential failure mechanisms. As a consequence, both the membrane and the flexural behaviours of masonry walls have to be taken into account for a proper estimation of the structural stability.

Macrosopic models used in structural computations are based on phenomenological laws including a set of parameters which characterises the average behaviour of the material. These parameters need to be identified through experimental tests, which can become costly due to the complexity of the behaviour particularly when cracks appear. The existing macroscopic models are consequently restricted to particular assumptions. Other models based on a detailed mesoscopic description are used to estimate the strength of masonry and its behaviour with failure. This is motivated by the fact that the behaviour of each constituent is a priori easier to identify than the global structural response. These mesoscopic models can however rapidly become unaffordable in terms of computational cost for the case of large-scale three-dimensional structures.

In order to keep the accuracy of the mesoscopic modelling with a more affordable computational effort for large-scale structures, a multi-scale framework using computational homogenisation is developed to extract the macroscopic constitutive material response from computations performed on a sample of the mesostructure, thereby allowing to bridge the gap between macroscopic and mesoscopic representations. Coarse graining methodologies for the failure of quasi-brittle heterogeneous materials have started to emerge for in-plane problems but remain largely unexplored for shell descriptions. The purpose of this study is to propose a new periodic homogenisation-based multi-scale approach for quasi-brittle thin shell failure.

For the numerical treatment of damage localisation at the structural scale, an embedded strong discontinuity approach is used to represent the collective behaviour of fine-scale cracks using average cohesive zones including mixed cracking modes and presenting evolving orientation related to fine-scale damage evolutions.

A first originality of this research work is the definition and analysis of a criterion based on the homogenisation of a fine-scale modelling to detect localisation in a shell description and determine its evolving orientation. Secondly, an enhanced continuous-discontinuous scale transition incorporating strong embedded discontinuities driven by the damaging mesostructure is proposed for the case of in-plane loaded structures. Finally, this continuous-discontinuous homogenisation scheme is extended to a shell description in order to model the localised behaviour of out-of-plane loaded structures. These multi-scale approaches for failure are applied on typical masonry wall tests and verified against three-dimensional full fine-scale computations in which all the bricks and the joints are discretised.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Neto, Benigno José dos Santos. ""Análise das falhas mais freqüentes encontradas na construção civil segundo as queixas feitas ao CREA-PE"." Universidade Católica de Pernambuco, 2006. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=38.

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Os produtos e serviços de arquitetura e engenharia precisam atender com qualidade as expectativas e necessidades de quem os contratam. Esta dissertação apresenta um levantamento das queixas mais freqüentes dos consumidores da cidade do Recife e Região Metropolitana a Assessoria de Defesa do Consumidor - ADC, que funciona dentro Conselho Regional de Engenharia, Arquitetura e Agronomia do Estado de Pernambuco CREA - PE, sobre os defeitos encontrados decorrentes dos erros cometidos no processo da indústria da construção civil, e a partir deles diagnosticar as suas causas e as razões que levaram à sua ocorrência. Busca-se com a análise dos mesmos, subsídios para indicar a prevenção e/ou remediação dos problemas detectados. Espera-se que a partir deste diagnóstico seja possível, inclusive, sugerir a instalação de uma educação continuada nos mais diversos níveis do ensino da engenharia
The products and services of architecture and engineering need to assist with quality, the expectations and needs of who hire them. This research project proposes the accomplishment of an inventory of the city of Recife consumers' most frequent complaints to Consumer Defense Consultantship ADC, that works inside of the Regional Council of Engineering, Architecture and Agronomy of the State of Pernambuco CREA - PE, and starting from them to identify causes and reasons that made their occurrence. The data will also be researched along with the builders, through the reports of final evaluation of their constructions. It will also be studied some tragedies in the civil construction where these structures collapsed. By the analysis of them, we look for subsidies for the prevention and/or remediation of the detected problems. Besides, it is expected that starting from this diagnosis it will be possible to trace guidelines for continuous education in the most several levels

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Santos, Neto Benigno José dos. ""Análise das falhas mais freqüentes encontradas na construção civil segundo as queixas feitas ao CREA-PE"." Universidade Católica de Pernambuco, 2006. http://tede2.unicap.br:8080/handle/tede/44.

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Made available in DSpace on 2017-06-01T17:57:28Z (GMT). No. of bitstreams: 1 benigno.pdf: 3630982 bytes, checksum: 145549a81097148696e4a7118a0508af (MD5) Previous issue date: 2006-07-25
The products and services of architecture and engineering need to assist with quality, the expectations and needs of who hire them. This research project proposes the accomplishment of an inventory of the city of Recife consumers' most frequent complaints to Consumer Defense Consultantship ADC, that works inside of the Regional Council of Engineering, Architecture and Agronomy of the State of Pernambuco CREA - PE, and starting from them to identify causes and reasons that made their occurrence. The data will also be researched along with the builders, through the reports of final evaluation of their constructions. It will also be studied some tragedies in the civil construction where these structures collapsed. By the analysis of them, we look for subsidies for the prevention and/or remediation of the detected problems. Besides, it is expected that starting from this diagnosis it will be possible to trace guidelines for continuous education in the most several levels
Os produtos e serviços de arquitetura e engenharia precisam atender com qualidade as expectativas e necessidades de quem os contratam. Esta dissertação apresenta um levantamento das queixas mais freqüentes dos consumidores da cidade do Recife e Região Metropolitana a Assessoria de Defesa do Consumidor - ADC, que funciona dentro Conselho Regional de Engenharia, Arquitetura e Agronomia do Estado de Pernambuco CREA - PE, sobre os defeitos encontrados decorrentes dos erros cometidos no processo da indústria da construção civil, e a partir deles diagnosticar as suas causas e as razões que levaram à sua ocorrência. Busca-se com a análise dos mesmos, subsídios para indicar a prevenção e/ou remediação dos problemas detectados. Espera-se que a partir deste diagnóstico seja possível, inclusive, sugerir a instalação de uma educação continuada nos mais diversos níveis do ensino da engenharia

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Gouveia, Lucas Pereira de. "Avaliação da conﬁabilidade em tubos de revestimento de poços de petróleo." Universidade Federal de Alagoas, 2014. http://www.repositorio.ufal.br/handle/riufal/3505.

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This work aims to evaluate the reliability levels associated to a probabilistic approach of mechanical strength models of casing tubes on oil and gas wells. A comparative study between different reliability evaluation methods commonly applied is also carried out. On the oil and gas well design, casing tubes must bear the mechanical loadings in the subsurface, such as the ones from formations, from drilling and completion ﬂuids, from production ﬂuid over the well lifetime, from the self-weight of casing column and from weight of other components. Reliability-based analysis applied to a structural design allows the assessment of the probability of violation for a given limit state of the structure, so that it can be predicted with adequate value since the design stage. This kind of analysis is useful to obtain adequate safety levels in design and to discuss the quality control level in the manufacturer production process. In this work, the failure probability is evaluated by the following reliability methods: failure domain numericintegration,MonteCarlosimulationandthetransformationmethods:FirstOrder eliabilityMethod(FORM)andSecondOrderReliabilityMethod(SORM).Thelimitstatesv riﬁed are established by using casing strength models found in the literature, based on mechanics of materials theory and rupture test data.Statistical data are based on technical reports from casing manufacturers found in open-access literature. The achieved results contributes to well casing structural assessment taking into account the inﬂuence of design uncertainties, motivating the adoption of reliability-based analysis in decision-making process on OCTG design.
FUNDEPES - Fundação Universitária de Desenvolvimento de Extensão e Pesquisa
Estetrabalho visa avaliar os níveis de conﬁabilidade associados a uma abordagem probabilística das resistências mecânicas de tubos de revestimento em poços de petróleo. Além disso, durante as análises realizadas, objetiva-se comparar os diferentes métodos de conﬁabilidade comumente encontrados na literatura com a ﬁnalidade de identiﬁcar o método mais vantajoso para a aplicação proposta. Em projetos de poços de petróleo e gás natural, os revestimentos exercem o papel de resistir mecanicamente aos esforços existentes na subsuperfície, como as solicitações impostas pela formação, pelo ﬂuido de perfuração, pelos ﬂuidos produzidos ao longo da vida útil do poço e pelos pesos da própria coluna de revestimento e de outros equipamentos. Já a análise de conﬁabilidade, aplicada a um projeto estrutural, permite a avaliação da probabilidade de violação de um determinado estado limite da estrutura, de forma que esta pode ser prevista, com valor adequado, ainda na fase de projeto.Esse tipo de análise é útil não obtenção da margem de segurança adequada do projeto e na discussão do nível de controle no processo de produção de elementos estruturais. Neste trabalho, o cálculo da probabilidade de falha é realizado através dos seguintes métodos: integração numérica sobre o domínio de falha, simulação de Monte Carlo e dos métodos de transformação: First Order Reliability Method (FORM) e Second Order Reliability Method (SORM). Os estados limites dos tubos são estimados por modelos de resistência encontrados na literatura, baseados em teorias da mecânica dos materiais e em dados de ensaios de ruptura. Os dados estatísticos utilizados são baseados em relatórios técnicos de produção disponíveis na literatura sob domínio público. Os resultados obtidos contribuem para a avaliação estrutural de revestimentos de poços de petróleo sob a inﬂuência de incertezas de projeto, motivando a incorporação da análise de conﬁabilidade no processo de tomada de decisão do projetista.

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Chana, Palvinder Singh. "Shear failure of reinforced concrete beams." Thesis, University College London (University of London), 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282869.

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Dissertations / Theses on the topic 'Structural failures'

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