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Reports on the plan of the 'Journal of Bridge Engineering' to publish a special issue on bridge management systems.

Addresses the security concerns in conducting electronic transactions in architecture/engineering/construction (A/E/C) projects by developing a framework for conducting secure and legally binding electronic transactions. Review of security in existing Web-based project management systems; Solution to the problem of securing electronic information after a transaction has been committed; Source of information in large scale A/E/C projects.

As emerging high-performance concrete, the engineered cementitious composite (ECC) has demonstrated excellent application potential in civil engineering. With the wide application of ECC, it not only excels in the tension state and the structural elements but also in the more complex stress state of nonuniform confinement. For a reliable and economic ECC element design, understanding the dilation behavior of ECC is crucial under complicated stress conditions. This paper presents an experimental investigation and a detailed discussion of the ECC dilation characteristics under different confinement rigidities. The authors evaluate the effects of column parameters, such as different types of fiber-reinforced polymer (FRP) composites, confinement levels, and cross-sectional shapes. Test results indicate that the ECC dilation amplitude (secant dilation) under FRP confinement is less than that of concrete due to fiber bridge effects within ECC. However, the maximum dilation rate (tangent dilation ratio) shows an opposite trend. Based on the data analysis in this study, a new lateral strain-to-axial strain model was proposed, which can predict the dilation behavior of FRP-confined ECC with nonuniform confining pressure. The proposed model not only accurately captures the dilation process of FRP-confined ECC but also precisely predicts its ultimate strain. In addition, the existing peak strength and ultimate strength models were also evaluated by the ECC test results. The comparison indicates that the strength models for concrete also apply to FRP-confined ECC when the ultimate hoop-confining stress is accurately determined. [ABSTRACT FROM AUTHOR]

Presents a list of research papers on cold regions engineering.

Introduces the August 2005 issue of the "Journal of Structural Engineering". Special theme section of the papers that deal with various research aspects related to a structure's response to blast and impact loads; Article on whether seismic design provisions can improve the resistance of buildings to blast loads and progressive collapse; Integration scheme that makes use of higher-order polynomial approximations.

Presents an introduction to various articles published in the January 2005 issue of the "Journal of Structural Engineering."

The section introduces several articles within the issue of the "Journal of Management in Engineering," including one article about a process of risk identification and assessment in the Polish construction market and another paper about an underground railway extension project in Hong Kong, China.

The article presents a list of research papers on topics related to hydraulic engineering published in the February 2006 issue of the "Journal of Hydraulic Engineering." The papers include "Effect of Media Grain Shape on Particle Capture During Filtration," by J. M. H. Barton and S. G. Buchberger, "Lime-Soda Softening Process Modifications for Enhanced NOM removal," by M. Bob and H. W. Walker, and "On the Fully Nonlinear Boussinesq-Type Equations for Waves and Currents Over Porous Beds," by Q. Chen.

Recent developments in technology, such as building information models (BIMs), immersive displays, and mobile computing tools, have enabled changes in the means and locations of communication throughout the building architecture, engineering, construction, and operation (AECO) industry. This paper presents the findings from an exploratory study regarding the planning of physical media for effective communication in conjunction with the developments in BIM use. While literature shows that there has been noticeable impact of physical media on communication, there has been little evidence of consistent and thorough planning and evaluation of media for investment or project level planning. The exploratory study identifies media synchronicity theory as a starting point for identifying the media needs by task for more effective planning of communication, as well as potential considerations unique to the AECO industry. The paper concludes with studies which have begun for planning more specific applications for BIM and media within AECO. [ABSTRACT FROM AUTHOR]

This paper suggests the methodology to follow when conducting discrete-event simulation (DES) studies in construction engineering and management research. Emphasis is made on the steps that, due to the uniqueness of the construction environment, are particularly important yet are not discussed extensively in the general DES literature. Guidelines are provided to determine what aspects of a DES study demand a rigorous application of the theory depending on the purpose of the study. The paper concludes with the importance of properly understanding the probabilistic concepts upon which DES relies and on coupling this understanding with engineering judgment as a key for successful use of DES in construction research. [ABSTRACT FROM AUTHOR]

Data envelopment analysis (DEA) is a mathematical method based on production theory and the principles of linear programming. It enables one to assess how efficiently a firm, organization, agency, or such other unit uses the resources available (inputs) to generate a set of outputs relative to other units in the data set. Recent papers by different writers present different applications of DEA in the transportation engineering domain. All of these papers are published in transportation journals. These papers are mainly aimed at addressing the transportation-related issues and thus do not focus too much on the DEA concept itself. It can be asserted that DEA is very likely to be used more and more in the transportation engineering domain. Given this, there is a need for the transportation professionals to fully understand the DEA concept. It is essential for such a community to identify cases where the application of this innovative and powerful method can be useful to help the decision-making process, to accurately apply DEA in a particular setting, to derive meaningful conclusions from the obtained results, and to acknowledge the limitations of DEA in certain cases so as to approach the results with caution. The purpose of this paper is to illustrate to the civil engineering, more specifically to the transportation engineering community the use of this powerful approach in performing comparative performance measurement. Within this context, this paper will address a transportation-related problem by using the DEA approach. Different from the other papers containing transportation-related DEA applications (as mentioned above), this paper will discuss, in detail, the steps that need to be taken to generate the DEA model and solve it. [ABSTRACT FROM AUTHOR]

Presents papers about bridge engineering. Repair of steel composite beams; Baseline models for bridge performance monitoring; Fatigue behavior of reinforced-concrete beams.

The construction industry is a major player in the nation's economy. The complex nature of the construction industry, coupled with the challenges of global competitiveness and changing regulatory requirements, has created the need for providing higher levels of education, experience, and training for construction professionals. An essential and integral component of the required education and training must be the research training of undergraduate civil and construction students, encouraging them to pursue advanced education and research careers in this area. With this in mind, the writer developed a Research Experiences for Undergraduates (REU) summer program at Western Michigan University that focuses on construction engineering and management issues and problems. This construction-oriented undergraduate research training program is the first REU site in the United States to be funded by the National Science Foundation. This paper will describe the structure of the REU program, the types of activities undertaken by the REU participants, and the results of the program evaluation and assessment. [ABSTRACT FROM AUTHOR]

As inelastic design for wind is embraced by the engineering community, there is an increasing demand for computational tools that enable the investigation of the nonlinear behavior of wind-excited structures and subsequent development of performance criteria. To address this need, a probabilistic collapse assessment framework for steel structures is proposed in this paper. The framework is based on the integration of a high-fidelity fiber-based nonlinear structural modeling environment with a wind-tunnel-informed stochastic wind load model to perform nonlinear time history analysis. General uncertainty is propagated using a stratified sampling scheme enabling the efficient estimation of reliabilities associated with rare events. The adopted models for simulating high-fidelity nonlinear structural behavior were found, in general, to be adequate for capturing phenomena, including progressive yielding, buckling, and low-cycle fatigue, that are essential for wind induced collapse analysis. In particular, the adopted fatigue model was found to be capable of predicting damage and potential fiber/section fracture associated with non–fully reversing stress-strain cycles that are characteristic of wind loading. Through illustration on a 45-story archetype steel building, critical discussions on the types of observed collapse mechanisms, the difference between along-wind and across-wind nonlinear behavior, reliabilities associated with first yield, and collapse are presented. A probabilistic description of the residual and peak story drifts is also provided through development of fragility functions. [ABSTRACT FROM AUTHOR]

A commentary on the article "Method of Solution of Nonuniform Flow with the Presence of Rectangular Side Weir," by Maurizio Venutelli is presented. The authors claim that the recommended technique integrates the variations along the side weir of the particular energy because of the bottom and friction slope. They consider the acceptability of the hypothesis of constant specific energy along the side weir. They offer experimental verification of simple numerical solution.

This article discusses the paper entitled "Head-Discharge Equation for Sharp-Crested Polynomial Weir," by Raouf E. Baddour. It extends an appreciation to Baddour for presenting an equation for polynomial weir design. It proposes a more convenient way to present equation 7 which could be achieved using the Gamma function. It illustrates a equations for a simpler solution to equation 7. It also presents an exact solution to proportional weir as illustrated in equation 3 of the paper. In addition a modified exact solution of a proportional weir is presented based on equation 15 of the paper.

Provides information on matters concerning civil engineering, structural design and construction.

Geopolymers have been long recognized as the next-generation building material due to environmental reasons. However, geopolymers are inherently brittle and usually require high-temperature curing. This paper was intended to develop a ductile engineered geopolymer composite (EGC) under ambient curing conditions. Two types of metakaolin powder with different particle sizes were applied as the solid precursor. The tensile, compressive, and flexural behaviors of EGC with different mix designs were investigated. It was concluded that the combinational application of coarse and fine metakaolin is conducive to the tensile and compressive behaviors of EGC materials. As the alkali concentrations increased from 6 to 14 mol/L , the tensile and compressive strength of EGC increased, whereas the tensile ductility of EGC decreased gradually. Also, the SiO2/Na2O molar ratio had negligible influence on the tensile behavior of EGC, whereas the compressive strength decreased with the increase of SiO2/Na2O molar ratios. A numerical model to predict the flexural behavior of EGC was also proposed, and the accuracy was verified with experimental results. [ABSTRACT FROM AUTHOR]

This paper presents the results from a prediction event, organized by the University of Western Australia (UWA) and the National Geotechnical Centrifuge Facility (NGCF), and performed as part of the International Symposium on Frontiers in Offshore Geotechnics to assess uncertainty in predicting the monotonic and cyclic lateral response of conductors. Geotechnical professionals from around the world were invited to predict the response of a model conductor (a flexible pile) subjected to a series of loading sequences in a centrifuge. A normally consolidated fine-grained soil was used in the tests, which was characterized by soil elements and in-flight T-bar penetrometer testing. While some participants provided accurate predictions, the mean response was an overestimate of the monotonic and cyclic load at the pile head, which was significant for large and very small displacements. An analysis of the submissions is presented to quantify the variability of the predictions received, assess the consequences of each design, and relay the uncertainty associated with engineering judgment in design. [ABSTRACT FROM AUTHOR]

Although there have been several studies about using recycled aggregates to construct recycled aggregate base (RAB) layers, there is a lack of information about the effects of gradation of recycled concrete aggregate (RCA) materials on the performance of such layers. There is also limited information available regarding the use of RCA and recycled asphalt pavement (RAP) materials together in RAB layers. In this study, three test cells were constructed with RAB layers using two different RCA materials with different gradations and a blend of RCA and RAP materials, and another cell was constructed with a natural aggregate base layer. Physical characteristics of the base layer aggregates were determined, and resilient modulus (MR) tests were performed. A series of falling weight deflectometer (FWD) tests were performed in the field, and changes in air and soil temperatures over time were monitored. This paper contains detailed information about the evaluation of the engineering properties of recycled aggregates and the preliminary performance of the constructed RAB layers. [ABSTRACT FROM AUTHOR]

The author reflects on the importance of peer review of articles published in "The Journal of Bridge Engineering." He calls for qualified associate editors and reviewers in the bridge engineering community to assist in reviewing and processing of papers submitted. He also calls for feedbacks and inputs from the readers in the community for significant contributions.

Modern society is demanding that the use of energy associated with construction and operation of structures be investigated during the planning and design phases. The engineering community has been striving to design more sustainable buildings in an attempt to reduce both raw material requirements and energy use during all phases of design. Structural engineers currently have very limited guidance on how to incorporate sustainability concepts in their designs. Innovative methods are needed to address the environmental impact, energy use, and other sustainability issues faced during planning and design of buildings. This paper investigates and discusses five sustainable structural design methodologies: Minimizing Material Use, Minimizing Material Production Energy, Minimizing Embodied Energy, Life-Cycle Analysis/Inventory/Assessment, and Maximizing Structural System Reuse. The goal of this paper is to describe and address issues associated with the proposed design methodologies to determine which, if any, can produce the most sustainable structural designs. It was determined that no single methodology can address all the issues surrounding sustainable structural design. Also, it was determined that combinations of two or more methodologies may increase the ability of design professionals to produce more sustainable designs. [ABSTRACT FROM AUTHOR]

The article lists papers of interest to bridge engineers as of January 2006. The list includes "Evaluation of GFRP honeycomb beams for the O'Fallon Park Bridge" by G. Camata and B. Shing, "Theoretical study on strengthening for increased shear bearing capacity" by A. Carolin and B. Tăljsten, "Wind-induced self-excited loads on bridges," by Z. Q. Chen, X. D. Yu, G. Yang and B. F. Spencer and "Field investigation on the first bridge deck slab reinforced with glass FRP bars constructed in Canada," by E. El-Salakawy, B. Benmokrane, A. El-Ragaby and D Nadeau.

Transportation networks are critical lifelines and their functionality after an earthquake is of primary importance for life safety and economic recovery of a community, yet they can be severely damaged during earthquakes. Reinforced concrete bridges are particularly vulnerable segments of these networks and have been severely damaged in past earthquakes. Past approaches for estimating traffic disruptions due to earthquakes have relied on computationally expensive simulations and have tended to overestimate postearthquake traffic volumes. This paper makes use of predictive fragility estimates to compute the conditional probability that a bridge in the network attains or exceeds a specified performance level for a given value of the ground motion intensity. The predictive fragilities incorporate the relevant sources of uncertainty inherent in the phenomenon. The focus of the paper is on network connectivity rather than traffic flow. The outcomes of the proposed approach can then be used by traffic models to accurately reflect postdisaster conditions. A block sampling-based simulation technique is used to estimate the network connectivity. This new approach provides a convenient, quick estimation of network reliability that complements computationally expensive traffic models. [ABSTRACT FROM AUTHOR]

This paper presents a new one-equation model, and case studies utilizing it, for evaluating the thermal effectiveness of slab-on-grade perimeter insulation in common wood-framed buildings for any time period such as a month, a season, or an entire year. Many previous studies focused on heat losses in very cold climates, but this new model can be effective for both heating and cooling in potentially any climate that has coefficients available. Two case studies, of residential and commercial buildings, are presented in this paper for three levels of foundation insulation and for three different, somewhat-warm to somewhat-cold, climates. Economic analyses of their heating seasons, cooling seasons, and annual performance are then presented, and the overall worthiness of the insulation, from energy cost and other perspectives, is discussed. The hand calculation method presented differs from previous efforts because it uses a new, single transient analytical equation and site-specific coefficients. The model gives designers, builders, and code officials, for example, the specific, defensible information needed to make decisions on whether insulation is needed. For the residential and commercial building examples presented at least a minimal amount of perimeter insulation is justified, both thermally and economically, for at least two of the three locations studied. [ABSTRACT FROM AUTHOR]

The article describes the need of Associate Editors and reviewers in bridge engineering community for the "Journal of Bridge Engineering." Associate Editors and the reviewers are the two cornerstones of this journal. The only purpose of this journal is to provide its readers with quality papers on current bridge engineering topics and issues. Reviewers are generally asked to review only one paper a year, unless they indicate that they can and are willing to review papers more frequently. The article also seeks inputs and feedbacks from the readers.

Seasonal cycles of moisture and suction variation in shallow clay masses create repeating episodes of soil shrinkage and swelling that can adversely affect a wide variety of structures including pavements, shallow foundations, piers, and slopes. Design of such structures requires a means of adequately characterizing the depth of this moisture active zone and the magnitude of suction variations within the zone. This paper describes an analytical framework for characterizing suction variations in the moisture active zone and for estimating the soil mass moisture diffusion coefficient, one of the critical parameters governing the rate of moisture penetration in the soil. The paper presents extensions to an existing analysis for sinusoidal variations in surface suction to general nonsinusoidal conditions. It also presents a review of moisture diffusion coefficient data obtained from field measurements and shows that these data exceed laboratory measurements on intact soil specimens by up to two orders of magnitude. A conceptual model of moisture diffusion in a fractured soil mass provides an explanation of the differences between the field and laboratory values of the moisture diffusion coefficient. [ABSTRACT FROM AUTHOR]

This paper introduces the concept of microscopic simulation system scalability for the purpose of reducing the computational requirements of microsimulation modeling of large-scale traffic networks. This exploratory stage of research investigates scalability of both lane-changing and car-following behavior. The main objective of the proposed methodology is to create a reduced-scale network (microcosm) that retains most of the significant characteristics of the full-scale network (prototype). To achieve this objective a systematic downsampling procedure has been applied to a case study of a one-lane homogeneous freeway corridor in order to create a geometrically, kinematically, and behaviorally equivalent microcosm environment. This paper examines the scalability of lane-changing behavior, assuming a shifted negative exponential headway distribution, and investigates the scalability of car-following behavior under various operating conditions and downsampling ratios. The paper focuses on the tradeoff between performance and scalability of microscopic simulation systems. For each of the 48 cases considered, optimal behavioral parameters were determined based on two optimization methods: (1) Microscopic based on minimization of trajectory errors in both environments and (2) macroscopic derived from minimization of density errors in both environments throughout the simulation period. The results show that both optimization solutions were consistent in determining the optimal behavioral parameters. [ABSTRACT FROM AUTHOR]

This paper presents research results that describe how value generation can be improved in the design process of industrial projects when using computer advanced visualization tools (CAVT). The CAVT concept definition, prior studies about impacts of CAVT, and why they are not sufficient are presented in the paper, supporting the assertion that the extensive attention to technology instead of to the context of technology application and the lack of a conceptual framework has prevented some prior research about CAVT impacts to truly focus in ideas about how to improve engineering and construction processes. Combining production theory and lean construction principles with information technology (IT), a framework for understanding the impacts of CAVT developed as part of the research is proposed. Illustration of the use of the framework in a case study and research validation activities leads to analytic generalization of the research results. [ABSTRACT FROM AUTHOR]

Provides information on the editorial board members of a journal on transportation engineering. Darcy Bullock; Kieran Feighan; Chris T. Hendrickson; Matthew G. Karlaftis.

The article offers announcements related to engineering in the United States. The terms progressive and disproportionate collapse of buildings are discussed. The 2005 Outstanding Paper "Membrane and Flashing Defects in Low-Slope Roofing: Causes and Effects on Performance," by David M. Bailey and Dane Bradford, which was selected by the American Society of Civil Engineers, is published in this journal. The author called for nominations for the 2006 Outstanding Paper Award.

Funicular geometries, which follow the idealized shapes of hanging chains under a given loading, are recognized as materially efficient structural solutions because they exhibit no bending under design loading, usually self-weight. However, there are circumstances in which nonstructural conditions make a funicular geometry difficult or impossible. This paper presents a new design philosophy, based on graphic statics, that shows how bending moments in a nonfunicular two-dimensional curved geometry can be eliminated by adding forces through an external posttensioning system. An interactive parametric tool is introduced for finding the layout of a posttensioning tendon for any structural geometry. The effectiveness of this approach is shown with several new design proposals. [ABSTRACT FROM AUTHOR]

Focuses on the American Society of Civil Engineers and Systems Engineering and Integration awards. Objective of the awards; Categories of the awards.

Reports that the 'Journal of Surveying Engineering,' will move to a larger format in 2003. Need for more manuscripts to maintain the larger format; Call for papers on practical issues and new technologies; View that there needs to be a balance of papers on theory and practice.

This paper presents the findings from a study of the breakdown of project success criteria. An exploration of the evolution of studies on the success of engineering projects over decades was the basis for a project success definition proposal. Using a comprehensive literature review of success criteria for engineering projects, a list of 133 different success criteria was identified. Those criteria were analyzed to develop an integrated framework of project success criteria, describing its hierarchical decomposition. Such a breakdown structure could serve as a starting point when setting project success criteria for a specific project, because the importance of criteria will be context dependent. Practitioners or stakeholders could discuss and tailor it based on specific features of engineering projects or specific needs and interests. Generally, criteria have evolved from simple work-related factors to focusing more on the complex benefits of the projects. Such an evolving success definition has implications for further studies of project success and might contribute toward a long-term vision in which all projects will be delivered successfully. [ABSTRACT FROM AUTHOR]

Drilling is a material removal process that introduces the plastic deformation and stresses around the hole. When large amounts of drilling stresses are added up, there will be deformation in the aerostructural assembly. This paper presents an aerostructural assembly deformation predicting method considering drilling-induced stresses around the riveting hole. Drilling-induced stresses are simulated with additional temperature fields. The assembly of the two riveted plates are considered to illustrate effects of drilling-induced stresses coupling and validate the proposed model. The simulation and experimental results show that one hole's drilling-induced stresses have negligible impact on the riveting deformation, while a lot of holes' drilling-induced stresses must be considered in assembling. When a lot of drillinginduced stresses are added up, there will be significant deformation in the aircraft's structure. The deformation predicting method outlined in this paper will enhance the understanding of the compliant components deformation resulting from the drilling stresses and help systematically improve the precision control efficiency in the civil aircraft industry. [ABSTRACT FROM AUTHOR]

One key issue in the simulation of bare electrodynamic tethers (EDTs) is the accurate and fast computation of the collected current, an ambient dependent operation necessary to determine the Lorentz force for each time step. This paper introduces a novel semianalytical solution that allows researchers to compute the current distribution along the tether efficient and effectively under orbital-motion-limited (OML) and beyond OML conditions, i.e., if tether radius is greater than a certain ambient dependent threshold. The method reduces the original boundary value problem to a couple of nonlinear equations. If certain dimensionless variables are used, the beyond OML effect just makes the tether characteristic length L* larger and it is decoupled from the current determination problem. Avalidation of the results and a comparison of the performance in terms of the time consumed is provided, with respect to a previous ad hoc solution and a conventional shooting method. [ABSTRACT FROM AUTHOR]