Civil Engineering Commons^™

Review: Inelastic Constitutive Modeling: Polycrystalline Materials, Mirza Baig, Josiah Owusu-Danquah, Anne A. Campbell, Stephen F. Duffy Phd, Pe

Civil and Environmental Engineering Faculty Publications

This article provides a literature review that details the development of inelastic constitutive modeling as it relates to polycrystalline materials. This review distinguishes between inelastic constitutive models that account for nonlinear behavior at the microstructural level, time-independent classic plasticity models, and time-dependent unified models. Particular emphasis is placed on understanding the underlying theoretical framework for unified viscoplasticity models where creep and classical plasticity behavior are considered the result of applied boundary conditions instead of separable rates representing distinct physical mechanisms. This article establishes a clear understanding of the advantages of the unified approach to improve material modeling. This review also …

Numerical Evaluation Of The Extended Endplate Moment Connection Subjected To Cyclic Loading, Mehdi Ghassemieh, Mehdi Jalalpour, Ali Akbar Gholampour

Civil and Environmental Engineering Faculty Publications

In this paper, the seismic behaviour of extended endplate moment connection is analysed using finite element method (FEM). First, an existing test setup is modelled and analysed using ANSYS computer program. The model is validated by comparing the results from the finite element with the experimental ones. Afterwards, by changing the dimensions of members of the connection, their effect on the overall seismic performance of connection is investigated. The results show that by enlarging the column depth and stiffening the connection, the seismic performance is improved and the thickness of endplate should be chosen in a way that its moment …

The Spatial Distribution Of Cancer Incidence In Fars Province: A Gis-Based Analysis Of Cancer Registry Data, Ali Goli, Mahbobeh Oroei, Mehdi Jalalpour, Hossein Faramarzi, Mehrdad Askarian

Civil and Environmental Engineering Faculty Publications

Background: Cancer is a major health problem in the developing countries. Variations of its incidence rate among geographical areas are due to various contributing factors. This study was performed to assess the spatial patterns of cancer incidence in the Fars Province, based on cancer registry data and to determine geographical clusters.

Methods: In this cross sectional study, the new cases of cancer were recorded from 2001 to 2009. Crude incidence rate was estimated based on age groups and sex in the counties of the Fars Province. Age standardized incidence rates (ASR) per 100,000 was calculated in each year. …

Another Look At The Collapse Of Skyline Plaza At Bailey’S Crossroads, Virginia, Jeffrey Schellhammer, Norbert Delatte, Paul A. Bosela

Civil and Environmental Engineering Faculty Publications

On March 2, 1973, the Skyline Plaza apartment building in Bailey’s Crossroads, Virginia collapsed while under construction. The Occupational Health and Safety Administration (OSHA) requested an investigation from the National Bureau of Standards [(NBS); now the National Institute of Standards and Technology (NIST)]. The NBS team concluded that the most likely cause of the collapse was a punching shear failure of the 23rd floor slab. The two factors that contributed to this were premature removal of shores below the 23rd floor slab, and the low strength of the 23rd floor concrete in the area supporting the weight of the 24th …

1976 Montreal Olympics: Case Study Of Project Management Failure, Ashish Patel, Paul A. Bosela, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

A successful engineering project must include its timely and economic completion. A project management failure can lead to delays and cost overruns. One example of a project that greatly exceeded its projected budget is the construction of the multiple facilities for the 1976 Olympic Games in Montreal. These included the Olympic Stadium, a velodrome for bicycle events, and the Olympic Village to house the athletes. This case study reviews the circumstances of the cost increases and the design decisions and other circumstances that led to them. The difficulties were brought on by an unrealistic schedule to complete the facilities before …

Influenza Forecasting With Google Flu Trends, Andrea Freyer Dugas, Mehdi Jalalpour, Yulia Gel, Scott Levin, Fred Torcaso, Takeru Igusa, Richard E. Rothman

Civil and Environmental Engineering Faculty Publications

Background: We developed a practical influenza forecast model based on real-time, geographically focused, and easy to access data, designed to provide individual medical centers with advanced warning of the expected number of influenza cases, thus allowing for sufficient time to implement interventions. Secondly, we evaluated the effects of incorporating a real-time influenza surveillance system, Google Flu Trends, and meteorological and temporal information on forecast accuracy.

Methods: Forecast models designed to predict one week in advance were developed from weekly counts of confirmed influenza cases over seven seasons (2004–2011) divided into seven training and out-of-sample verification sets. Forecasting procedures …

Interfacing Building Response With Human Behavior Under Seismic Events, Z. Liu, Mehdi Jalalpour, C. Jacques, S. Szyniszewski, J. Mitrani-Reiser, James K. Guest, T. Igusa, B. W. Schafer

Civil and Environmental Engineering Faculty Publications

The goal of this paper is to model the interaction of humans with their built environment during and immediately following a natural disaster. The study uses finite element simulations to evaluate the response of buildings under input ground motions and agent-based dynamic modeling to model the subsequent evacuation of building occupants in the study area immediately following the seismic event. The structural model directly captures building damage and collapse, as well as floor accelerations and displacements to determine nonstructural damage, injuries and fatalities. The goal of this research is to make connections between building damage and occupant injuries, with geographic …

Structural Topology Optimization: Moving Beyond Linear Elastic Design Objectives, James K. Guest, Reza Lotfi, Andrew T. Gaynor, Mehdi Jalalpour

Civil and Environmental Engineering Faculty Publications

Topology optimization is a systematic, free-form approach to the design of structures. It simultaneously optimizes material quantities and system connectivity, enabling the discovery of new, high-performance structural concepts. While powerful, this design freedom has a tendency to produce solutions that are unrealizable or impractical from a structural engineering perspective. Examples include overly complex topologies that are expensive to construct and ultra-slender subsystems that may be overly susceptible to imperfections. This paper summarizes recent tools developed by the authors capable of mitigating these shortcomings through consideration of (1) constructability, (2) nonlinear mechanics, and (3) uncertainties.

Optimal Design Of Trusses With Geometric Imperfections: Accounting For Global Instability, Mehdi Jalalpour, Takeru Igusa, James K. Guest

Civil and Environmental Engineering Faculty Publications

A topology optimization method is proposed for the design of trusses with random geometric imperfections due to fabrication errors. This method is a generalization of a previously developed perturbation approach to topology optimization under geometric uncertainties. The main novelty in the present paper is that the objective function includes the nonlinear effects of potential buckling due to misaligned structural members. Solutions are therefore dependent on the magnitude of applied loads and the direction of resulting internal member forces (whether they are compression or tension). Direct differentiation is used in the sensitivity analysis, and analytical expressions for the associated derivatives are …

Review Of "Handbook For Blast Resistent Design Of Buildings", Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Case Methods In Civil Engineering Teaching, Timothy A. Newson, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

English: There have been significant changes in undergraduate civil engineering curricula in the last two decades. Key issues for university curriculum committees are selection and transference of appropriate skills and attributes for students to succeed in the industry. Despite significant changes occurring in teaching theories, civil engineering education still relies heavily on deductive instruction. Case-based teaching is one of the most widespread forms of inductive learning and this paper describes the differences between two of the most familiar types: 'case-histories' and 'case-studies'. These methods are presented using the Kansas City Hyatt Regency walkway collapse as an exemplar. The benefits of …

Optimal Design Of Trusses With Geometric Imperfections, Mehdi Jalalpour, Takeru Igusa, James K. Guest

Civil and Environmental Engineering Faculty Publications

The present paper focuses on optimization of trusses that have randomness in geometry that may arise from fabrication errors. The analysis herein is a generalization of a perturbation approach to topology optimization under geometric uncertainties. The main novelty in the present paper is in the consideration of potential buckling due to misaligned structural members. The paper begins with a brief review of the aforementioned perturbation approach, then proceeds with the analysis of the nonlinear effects of geometric imperfection. The paper concludes with some numerical examples.

Collapse Of The Quebec Bridge, 1907, Cynthia Pearson, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

In the late 19th century, the transportation needs of Quebec led to proposals for bridging the St. Lawrence River. The Quebec Bridge was the longest cantilever structure attempted until that time. In its final design, the clear span was 548.6 m (1,800 ft) long. The bridge project was financially troubled from the beginning. This caused many setbacks in the design and construction. Construction finally began in October 1900. In August 1907, the bridge collapsed suddenly. Seventy five workers were killed in the accident, and there were only 11 survivors from the workers on the span. A distinguished panel was assembled …

Ronan Point Apartment Tower Collapse And Its Effect On Building Codes, Cynthia Pearson, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

In the early morning hours of May 16, 1968, the occupant of apartment 90 on the 18th floor of the 22-story Ronan Point apartment tower, in London, lit a match to brew her morning cup of tea. The resulting gas explosion initiated a partial collapse of the structure that killed four people and injured 17 (one of whom subsequently died). On investigation, the apartment tower was found to be deeply flawed in both design and construction. The existing building codes were found to be inadequate for ensuring the safety and integrity of high-rise precast concrete apartment buildings. The Larsen–Nielson building …

Failure Of Cold-Formed Steel Beams During Concrete Placement, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

During a concrete placement on the second story of a building under construction, the supporting cold-formed steel beams collapsed. Four workers were injured. The collapse occurred while concrete was being placed onto steel decking on the second floor of the structure. Cold-formed steel beams, without shoring, supported the steel decking. Analysis of the steel beams under the weight of concrete and workers using the applicable American Concrete Institute and American Iron and Steel Institute documents indicated that the beams were overstressed for construction loads. After the collapse, part of the structure was rebuilt using thicker beams. For the reconstruction, the …

Serviceability-Based Dynamic Loan Rating Of A Lt20 Bridge, P. Siswobusono, S.-E. Chen, S. Jones, D. Callahan, T. Grimes, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Effect Of Supplementary Cementitious Materials On The Compressive Strength And Durability Of Short-Term Cured Concrete, H. Toutanji, Norbert Delatte, S. Aggoun, R. Duval, A. Danson

Civil and Environmental Engineering Faculty Publications

This research focuses on studying the effect different supplementary cementitious materials (silica fume, fly ash, slag, and their combinations) on strength and durability of concrete cured for a short period of time—14 days. This work primarily deals with the characteristics of these materials, including strength, durability, and resistance to wet and dry and freeze and thaw environments. Over 16 mixes were made and compared to the control mix. Each of these mixes was either differing in the percentages of the additives or was combinations of two or more additives. All specimens were moist cured for 14 days before testing or …

Collapse Of 2000 Commonwealth Avenue: Punching Shear Case Study, Suzanne King, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

On January 25, 1971, two thirds of a 16-story apartment building collapsed while under construction at 2000 Commonwealth Avenue, Boston, Massachusetts. Four workers died after a failure on the roof instigated a progressive collapse all the way to the basement, where the men were found. Fortunately, the collapse occurred slowly enough for most of the other workers to run to safety. An investigation, conducted by a commission assembled by the Mayor of Boston, painted a picture of a troubled project, with considerable confusion about responsibility for structural safety. The surviving workers’ descriptions of the failure provide a textbook definition of …

Undergraduate Summer Research In Structural Engineering, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

For the last seven years, a summer Research Experiences for Undergraduates site in structural engineering, funded by the National Science Foundation, has operated at the University of Alabama at Birmingham. During this time, 33 students from 22 colleges and universities have participated in the site. Participants are recruited nationally and have come from as far away as California and Puerto Rico. The program is intended to provide students interested in graduate studies with an introduction to research methods, and to provide students who will not continue their studies past a bachelor of science in civil engineering with a better understanding …

Using The Ltpp Database In A Pavement Design Course, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

The Strategic Highway Research Program Long Term Pavement Performance (LTPP) database provides considerable information about a large number of pavement test sections. The information may be easily accessed using DataPave 2.0 software, available free from the Federal Highway Administration. This software provides information on approximately 3,000 sections, with several modules for data analysis and extraction. This paper describes the integration of LTPP DataPave 2.0 software into a pavement design course. The database was used at several points throughout the course, including lessons on traffic characterization, materials, reliability, performance, and design. Twelve Texas pavement case studies were used. Each student was …

Forensics And Case Studies In Civil Engineering Education: State Of The Art, Norbert J. Delatte, Kevin L. Rens

Civil and Environmental Engineering Faculty Publications

This paper reviews the state of the art in the use of forensic engineering and failure case studies in civil engineering education. The study of engineering failures can offer students valuable insights into associated technical, ethical, and professional issues. Lessons learned from failures have substantially affected civil engineering practice. For the student, study of these cases can help place design and analysis procedures into historical context and reinforce the necessity of lifelong learning. Three approaches for bringing forensics and failure case studies into the civil engineering curriculum are discussed in this paper. These are stand-alone forensic engineering or failure case …

Closure To “Another Look At The L’Ambiance Plaza Collapse,” By Rachel Martin And Norbert J. Delatte, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Lessons From Roman Cement And Concrete, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

Although masonry and lime mortars had been used for centuries by earlier civilizations, the Romans were the first to extensively use naturally occurring volcanic earth to make hydraulic cement. The volcanic powder named “pulvis puteolanis,” found near the town of Puteoli near Naples (now Pozzouli), was used to build magnificent structures. The use of this hydraulic cement in masonry and concrete greatly expanded civil engineering possibilities. The Roman engineer Vitruvius, writing in The Ten Books on Architecture, described the careful materials selection, proportioning, and workmanship that was critical to the performance of Roman concrete. Masonry and coarse and fine …

Another Look At Hartford Civic Center Coliseum Collapse, Rachel Martin, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

Only a few hours after five thousand basketball fans had left, the roof of the Hartford Civic Center Coliseum collapsed under a heavy snowfall. Fortunately, the arena was empty. The design of the space frame roof had been based on an innovative and extensive computer analysis. However, when deflections twice as great as those predicted by the computer analysis were observed during construction, the warning was ignored. Overconfidence in computer analysis results played a large part in this failure. A useful lesson from this case is that the computer is only an analytical tool and computed results must be checked …

Another Look At The L'Ambiance Plaza Collapse, Rachel Martin, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

The collapse of the L'Ambiance Plaza building, under construction in Bridgeport, Conn., in 1987, killed 28 construction workers. A number of concurrent investigations were undertaken to attempt to determine the cause. At least six separate theories were developed. However, a prompt legal settlement kept these investigations from being completed. This paper reviews the collapse and discusses the competing theories. The failure focused controversy on the safety of the lift-slab construction method. Because there is a need in civil engineering education for case studies to illustrate ethical and professional issues as well as technical principles, this paper also addresses these aspects. …

Closure To Discussion: Failure Case Studies And Engineering Ethics In Engineering Mechanics Courses, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Investigating Performance Of Bonded Concrete Overlays, Norbert J. Delatte, David W. Fowler, B. Frank Mccullough, Stefan F. Gräter

Civil and Environmental Engineering Faculty Publications

A bonded concrete overlay (BCO) is a concrete pavement rehabilitation method used to extend the life of an existing concrete pavement. The BCO should bond fully with the existing concrete, leading to a thicker composite pavement section, a much stiffer pavement, and a considerable decrease in pavement stresses. For one project, cost estimates for a BCO were half as much as for full-depth replacement of a pavement. In some cases BCOs have delaminated shortly after construction. This paper proposes a framework for identifying the causes of early age delamination in BCOs. The early age behavior of newly constructed BCOs is …

Failure Case Studies And Ethics In Engineering Mechanics Courses, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

Often, engineering students do not study engineering failures or discuss ethics until they take upper division undergraduate courses or graduate level courses. One drawback to this approach is that problems analyzed in introductory courses are often contrived, uninteresting, and bear little relation to the problems encountered in engineering practice. At the point when educators need to grab the student's interest in engineering most, they should show the excitement and relevance of the profession. Another is that the students encounter the issues of ethics, responsibility, and accountability that are often highlighted by a failure, late in their engineering education. As a …