ASCE Committee Research Articles

A parallelized algorithm to speed up 1D free-surface flow simulations in irrigation canals

AbstractA parallel algorithm for 1D free-surface flow simulations in irrigation canals is shown. The model is based on the Hartree method applied to Saint-Venant equations. Due to the close-to-steady flow nature in irrigation canals, external and internal boundary conditions are linearized to preserve the parallel character. Gate trajectories, off-take withdrawals, and external boundary conditions are modeled as piece-wise functions of time, so there are discontinuities. To achieve a fully parallelized algorithm, an explicit version of the Hartree method is chosen, and external and internal boundary conditions are linearized around operation point. This approach is used to build a computer simulator, written in C-CUDA language. Two tests by ASCE Committee on Canal Automation Algorithms have been used to evaluate accuracy and performance of the algorithm. The Maricopa Stanfield benchmark has been used to prove its accuracy, and the Corning Canal benchmark to evaluate performance in terms of processing time. Surprisingly, solving a 12 hr-long prediction horizon with a cell size of about Δx= 10 m is less than 1 s on a Nvidia K40 card. Results were compared with a serial and a multi-CPU version of the same algorithm. The implementation that showed the best performance on different platforms is the one that uses GPU.

Trends in Expectations about Duties and Responsibilities of Construction Managers

AbstractThis paper discusses the findings of a study conducted under the direction and supervision of the ASCE Committee on Management Practices in Construction (MPIC) to investigate the expectatio...

Duties and Responsibilities of Construction Managers: Perceptions of Parties Involved in Construction

This paper reports the findings of a study conducted by researchers at Illinois Institute of Technology under the direction and supervision of the ASCE Committee on Management Practices in Construction to investigate the expectations of the parties involved in the construction process, including designers, owners, general contractors, subcontractors, construction managers, and educators, relative to construction managers’ duties. The findings suggest that while there is some consensus among parties to a construction project relative to CM duties particularly in the construction phase, there is also some disagreement, most of which appear to be between contractors and designers. Most disagreements are related to CM duties performed in the bidding and postconstruction phases of projects.

The ASCE Committee of Global Principles for Professional Conduct

The ASCE Committee of Global Principles for Professional Conduct was formed to address corruption in the global engineering/construction industry. Among it’s many activities, the committee has brought anticorruption topics to ASCE annual meeting programs, developed policy statement 510 entitled “Combating Corruption,” developed an Engineer’s Charter, worked with other committees and groups to develop anticorruption education and training materials, and in general brought the topic of corruption in the engineering/construction industry to the forefront of discussions.

Boyd C. Paulson Jr.…Our History…PCCP Precast Panels…Books…Conferences

Boyd C. Paulson Jr., the Charles H. Leavell Professor of Civil Engineering at Stanford University and an international leader in construction education, died on December 1, 2005. Paulson’s father was a heavy-construction project manager whose work caused regular family moves to projects around the world. From the time of his birth in Providence, R.I., on March 1, 1946, Paulson was exposed to the world of construction. He earned three degrees in civil engineering from Stanford: B.S. in 1967, M.S. in 1969, and Ph.D. in 1971. After earning his doctorate, he moved to the University of Illinois as an assistant professor of civil engineering 1972 to 1974 , but Stanford soon lured him back to its graduate Construction Engineering and Management Program faculty in the Department of Civil and Environmental Engineering. During his years at Stanford, he also served as a visiting professor at the University of Tokyo 1978 , the Technical University of Munich 1983 , the University of Strathclyde, in Glasgow, Scotland 1990–1991 , and the University of Hawaii 1998 , and as a Visiting Eminent Scholar at the Del E. Webb School of Construction, Arizona State University 1996 . In 1995, he volunteered to oversee construction of Peninsula Habitat for Humanity’s $2 million, 24-unit condominium project for low-income residents in East Palo Alto, Calif. He eventually joined the organization’s board of directors. Paulson was a member of the Construction Institute, American Society of Civil Engineers, and served as chairman of the Construction Division the predecessor to the Construction Institute in 1986–1987. He chaired the ASCE Committee on Professional Construction Management from 1974 to 1977 and the National Science Foundation’s Civil and Environmental Engineering Division Advisory Committee from 1983 to 1989. He also served as vice chair of the U.S. National Committee on Tunneling Technology from 1986 to 1989 . Paulson was awarded ASCE’s Walter L. Huber Civil Engineering Research Prize in 1980, the Construction Management Award in 1984, and the Peurifoy Construction Research Award in 1993. Additionally, he was elected to the National Academy of Construction in 2001. To many of us who had the opportunity to know and work with Boyd personally, the awards represent only a small token of appreciation to a man who did so much for our profession and who took the time to mentor so many of us. Requiescat in pace

Associate Editor Changes

With this issue of the Journal of Bridge Engineering we would like to formally welcome nine new associate editors to the Journal. Dr. Anil K. Agrawal (Fig. 1) is a professor of civil engineering at the City College of the City University of New York. He received his Ph.D. degree in civil engineering from the University of California, Irvine, in August 1997 and joined the City College of New York in September 1998. He has published more than 40 journal papers and more than 100 conference papers and is currently a member of the executive committee of The U.S. Panel of the International Association of Structural Control and Health Monitoring, an executive committee member of the Northeast Region of the Advanced National Seismic System ANSS-NE , secretary of the ASCE Committee on Structural Control, and associate editor of the Journal of Structural Engineering. His areas of interest include earthquake engineering, structural dynamics, structural control, smart materials and systems, dynamical behavior of structures subject to blasts/explosive loads, structural health monitoring, bridge management systems, and asset management of physical infrastructures. Dr. Issam E. Harik (Fig. 2) is the Raymond-Blythe Professor of Civil Engineering and program manager of the Structures and Coatings Section at the Kentucky Transportation Center, University of Kentucky, Lexington, Kentucky. He received his Ph.D. degree from Wayne State University in 1982 and joined the University of Kentucky the same year. His research interests are in the areas of fiber-reinforced polymer composite components and structures, seismic analysis and retrofit of bridges, vessel impact on bridges, and homeland security and hazard management of highway structures. He currently serves as a member of 11 soci-

Advancing Sustainable Development of Infrastructure Systems

Sustainability is a concept born from the global movement toward better management of resources. A 1987 United Nations World Congress document ~called the Brundtland Report! defined sustainability as ‘‘management of resources such that current generations are able to meet their needs without affecting the ability of future generations to meet their needs.’’ This definition of sustainability has led experts in many disciplines—technical and social—to call for an increased concern for environmental and resource management within their fields. However, practical interpretations of this definition are still largely missing. These interpretations are mostly being advanced by academic researchers and have yet to be incorporated into corporate and governmental structures. Indeed, leaders in engineering, chemistry, economics, and philosophy have translated this concept of sustainability into a call for action. The field of civil and environmental engineering, while not a primary player in the sustainability movement, has not been idle. The ASCE Committee on Sustainability was formed in 2001 and includes a cross section of ASCE’s membership profile. For the past 2 years, there has been one session at the ASCE National Conference on the topic of sustainability in civil engineering, including discussions on the role of sustainability in civil and environmental engineering education. The 2003 ASCE Construction Research Congress had two sessions on sustainability, and more are planned for the 2005 meeting. The May 2004 ASCE Structures Congress included one session on economic and environmental life-cycle assessment. These efforts are a good professional starting point, but should not be seen as sufficient to enable the levels of change needed. The National Science Foundation—a primary source of funding for engineering research in the United States—has been supportive of sustainable engineering projects, including the Division of Civil and Mechanical Systems in the Engineering Directorate. Programs from the U.S. Department of Energy and the EPA have also been supportive of this area over the past decade. Current national environmental priorities are not necessarily in line with global sustainability goals. For example, United States policy is currently dubious of the implications and causes of global climate change from greenhouse gas emissions and atmospheric concentrations. The United States is not a player in the official global Kyoto Protocol implementation to reduce emissions to below 1990 levels. This could have the undesirable side effect of undermining our leadership positions in global environmental management, as well as in the development of environmental control technologies. Europe and Asia are poised to take over these leadership positions without further American efforts

Benchmark Structural Control Problems for Seismic- and Wind-Excited Structures

The theme of this special issue of the Journal is benchmark structural control problems for seismicand wind-excited structures. Tremendous progress has been made over the past 2 decades toward making structural vibration control a viable technology for enhancing structural functionality and safety against natural hazards, such as strong earthquakes and high winds. Over the years, many control algorithms and devices have been investigated, each with its own merits, depending on the particular application and desired effect. Clearly, the ability to make direct comparisons between systems employing these algorithms and devices is necessary to focus future efforts in the most promising directions and to effectively set performance goals and specifications. One approach to achieving this goal is to consider consensus approved, high-fidelity, analytical benchmark models that allow researchers in structural control to test their algorithms and devices and to directly compare the results. The ASCE Committee on Structural Control has recognized the significance of structural control benchmark problems. The Committee developed a benchmark study, focusing primarily on the comparison of structural control algorithms for three-story building models. An extensive analysis of these benchmark structural control problems formed the basis for a special issue of Earthquake Engineering and Structural Dynamics ~Spencer et al. 1998a,b!. Several of these algorithms also have been verified experimentally ~Baker et al. 1999!. Building on the foundation laid by the ASCE Committee on Structural Control, new generations of benchmark structural control studies were initiated by the Working Group on Building Control during the Second International Workshop on Structural Control held on December 18–20, 1996, in Hong Kong ~Chen 1996!. As stated by the Working Group, the goal of this effort was to develop benchmark models to provide systematic and standardized means by which competing control strategies, including devices, algorithms, and sensors, etc., can be evaluated. This goal drives the second generation of structural control benchmark problems. As an outgrowth of the workshop in Hong Kong, two benchmark problems for the control of buildings were developed for presentation at the 2nd World Conference on Structural Control held on June 28 to July 1, 1998, in Kyoto, Japan. The first benchmark problem, detailed in Yang et al. ~1999!, proposed a benchmark problem using a 76-story, wind-excited concrete tower designed for Melbourne, Australia. The second benchmark problem, detailed in Spencer et al. ~1999!, used a 20-story structure designed for the Los Angeles area. The structural model in the second benchmark problem was considered to remain perfectly elastic. However, large magnitude earthquakes can cause inelastic behavior in the structural element of civil structures, resulting in nonlinear responses. During the 2nd World Conference on Structural Control held in 1998 in

Probabilistic fatigue and fracture analyses of steel bridges

According to a study conducted by the ASCE Committee on Fatigue and Fracture Reliability, 80–90% of failures in steel structures are related to fatigue and fracture. Therefore, fatigue and fracture reliability is an important concern for steel bridges. In this study, the finite strip method is coupled with either the fatigue approach proposed by Wirsching, or the linear-elastic fracture mechanics (LEFM) approach as proposed by Harris (In: Sundararajan C, Ed. Probabilistic structural mechanics handbook [chapter 7]. New York: Chapman & Hall Ltd.; 1995. p 106–45.), for fatigue reliability analysis of steel highway bridges. The flat shell strips are employed to model the concrete slab and steel girders, while a connection strip is developed by means of the penalty function method in order to take into account the eccentricity of the top flange of girder. The loading effects are modeled by the fatigue truck developed by Laman and Nowak (Journal of Stuctural Engineering ASCE 1996:726). At each sampling point with given values of slab thickness and modulus ratio, a finite strip analysis of the bridge under fatigue truck is carried out, and the stress ranges at the fatigue-prone detail are calculated. According to these stress ranges and intended service life, the fatigue failure probability can be evaluated using the fatigue approach or the LEFM approach. After the failure probability is integrated over all sampling points, the fatigue reliability of the bridge is determined. Numerical examples are presented to illustrate the proposed methodology.

Sliding Mode Control of Cable-Stayed Bridge Subjected to Seismic Excitation

The working group on bridge control within the ASCE Committee on Structural Control recently initiated a first-generation benchmark problem addressing the control of a cable-stayed bridge subjected to seismic excitation. Previous research examined the applicability of a LQG-based semiactive control system using magnetorheological (MR) dampers to reduce the structural response of the benchmark bridge and confirmed the capability of the MR damper-based system for seismic response reduction. In this paper, sliding mode control (SMC) is applied in lieu of the LQG formulation to the benchmark bridge problem. The performance and robustness of the SMC-based semiactive control system using MR dampers (SMC/MR) is investigated through a series of numerical simulations, and it is confirmed that SMC/MR can be very effectively applied to the benchmark cable-stayed bridge, subjected to a wide range of seismic loading conditions.

Construction Considerations for Composite Steel-and-Concrete Floor Systems

This report presents an overview of construction methods for the most commonly used composite steel-and-concrete floor system in U.S. buildings. The report was prepared by a subcommittee of the ASCE Committee on Composite Construction and is intended to assist practitioners by summarizing practical and effective means to avoid common construction problems. Four principal components of the floor system are considered: (1) steel section, (2) steel deck, (3) headed shear stud, and (4) concrete slab. Proper construction procedures for each component are discussed and summarized. Reasonable adherence to specifications and communication between designers and builders will minimize difficulties in the construction of composite steel-and-concrete floor systems.

Compendium of Design Office Problems—Volume III

This is the third in a series of papers aimed at resolving structural engineering issues faced by the designers of steel building structures. The emphasis is on practical solutions that the designer can use directly, without extensive further research. Each issue is listed separately, with a technical discussion of the problem followed by a suggested solution, and references provided where appropriate. In addition, topics currently under study by the ASCE Committee on Design of Steel Building Structures are listed, as are subjects identified by the Committee as being in need of investigation.

Advances in Seismic Design and Evaluation of Steel Moment Frames: Recent Findings from FEMA/SAC Phase II Project

Advances in Seismic Design and Evaluation of Steel Moment Frames: Recent Findings from FEMA/SAC Phase II Project

Sliding mode fuzzy control: Theory and verification on a benchmark structure

A sliding mode fuzzy control (SMFC) algorithm is presented for vibration reduction of large structures. The rule base of the fuzzy inference engine is constructed based on the sliding mode control, which is one of the non-linear control algorithms. In general, fuzziness of the controller makes the control system robust against the uncertainties in the system parameters and the input excitation, and the non-linearity of the control rule makes the controller more effective than linear controllers. For verification of the present algorithm, a numerical study is carried out on the benchmark problem initiated by the ASCE Committee on Structural Control. To achieve a high level of realism, various aspects are considered such as actuator–structure interaction, sensor noise, actuator time delay, precision of the A/D and D/A converters, magnitude of control force, and order of control model. Performance of the SMFC is examined in comparison with those of other control algorithms such as Hmixed 2/∞, optimal polynomial control, neural networks control, and SMC, which were reported by other researchers. The results indicate that the present SMFC is efficient and attractive, since the vibration responses of the structure can be reduced very effectively and the design procedure is simple and convenient. Copyright © 2000 John Wiley & Sons, Ltd.

Results of Faculty Advisor Survey by ASCE Committee for Student Activities (CSA)

Results of Faculty Advisor Survey by ASCE Committee for Student Activities (CSA)

Limits of achievable performance and controller design for the structural control benchmark problem

In this work we give a methodology for controller design and analysis which accounts for design criteria such as: (a) optimal system response to external disturbances, (b) robustness to modelling uncertainty, and (c) constraints on the controller order. The methodology is applied to a structural control benchmark problem sponsored by the ASCE Committee on Structural Control. The structural system considered consists of a scale model of a three-storey building employing an active mass driver to suppress ground motion disturbances. The methodology proved effective for obtaining a satisfactory low-order controller for this class of problems.

ASCE Environmental Site Investigation Manual Put to Practical Use as an Industry Reference

From across the nation a task committee of recognized experts assembled to prepare a guidance manual for professionals involved in the due diligence evaluation of site contamination from oil or hazardous materials. This ASCE committee of 15 members was chaired by the first writer. The manual provides guidance for professionals involved in the determination of possible site contamination with oil or hazardous materials from preliminary assessments, to subsurface investigations, through remediation. The writers have used the manual repeatedly to establish the acceptable quality of environmental studies by others, and to reference in their environmental studies completed for clients. As environmental practitioners, they cited specific instances in which the manual has been most useful. Based upon their experience, the manual is becoming an accepted reference document in the industry with financial, legal, and engineering firms responsible for the due diligence needs of land parcels. The manual can become a stronghold in the industry given its comprehensive nature and timeliness, a first of its kind developed by a professional and technical organization.

Defining and Using Reference Evapotranspiration

Values of reference evapotranspiration (ET0) are used with crop coefficients (KC) for many aspects of irrigation and water resources planning and management. More than a score of methods are used for estimating ET0. Estimated values vary widely due to the lack of standardization of the reference. Evaporation (ET) measured by lysimeters of various grasses and/or alfalfas has been used as the standard for developing estimating equations. Due to variation in the references used, some international organizations now wish to promote the use of a single equation or method to avoid the confusion caused by the current diversity. Different versions of the Penman combination equation have been proposed. The Research Center for the European Community and the ASCE Committee on Irrigation Requirements have evaluated various equations for estimating ET0. Due to its simplicity and the accuracy of estimates, the 1985 Hargreaves et al. equation is recommended for general use. ET0 is used in irrigation planning, design, an...

Modern Communication as Training Aid

Technological advances in communication provide many opportunities that are not readily available to the practicing engineer for training, continuing education, and self-improvement needed to keep pace with his chosen field. Information management sciences offer a variety of ways to increase knowledge in a wide range of the latest in engineering and scientific developments. Communication by telephone, fiber-optic cable, microwave, and satellite is capable of providing interactive training over long distances. Educational and reference material is accessible by listening or viewing information available on photographic film, magnetic tapes and discs, memory chips, and laser discs and is available from several sources. Research by the ASCE Committee on Engineering Management at the Individual Level into the availability of training aids for engineers seeking better management and communication skills revealed a wide range of information sources in all types of media. This paper lists several of the organizations that conduct educational programs that are convenient, accessible, and reasonable in cost.

North American and British Long‐Span Bridge Loads

For many years, major bridges have been built without the designers having any specific basis for the traffic loads used in the design. Traffic loads are compared between codes in the United Kingdom, which has the longest span in the world, and in the United States, which has the second and third longest. Recent studies in the United States, Canada, and the United Kingdom have resulted in major changes to recommended long‐span bridge‐design loads. These, too, are compared. Multiple‐lane loading and impact are also discussed. The current British loading is similar to, but heavier than, the loading recommended by the ASCE Committee on Loads and Forces on Bridges.