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Over the last 30 years, the last planner system (LPS), as a Lean-driven production planning and control tool, has consistently demonstrated its capability to improve planning reliability and overall performance in construction projects. Recent research provides evidence suggesting that the LPS ability to do good to projects has not reached its full potential yet. In fact, it has been observed that by identifying the missing social mechanisms in its implementation process and managing more effectively the complex socio-technical nature of the LPS, its implementation effectiveness is improved. However, commonly used research approaches, such as the case study method, have been criticized for lacking scientific control, replicability, and external validity. Alternatively, immersive virtual reality (IVR)-based simulation games have the methodological capability to enable the study of the social mechanisms that the LPS engenders when implemented in projects, by providing a highly controlled, reproducible, and ecologically valid experimental environment. However, how to leverage effectively IVR-based gaming technology to study the social mechanisms that the LPS engenders in construction organizations is not well understood. In order to bridge this gap, this paper established the conceptual and technical foundations to set IVR-based experimental environments and developed an IVR prototype encompassing nonlean and LPS-based rounds. The evaluation of the IVR prototype involved both quantitative and qualitative research approaches, focusing on its functionality, user-perceived presence and usability, task performance, and lean expert feedback. The results demonstrated the prototype's capability to create a controlled experimental environment while offering participants a user-friendly, immersive, and realistic LPS simulation experience. The contributions of this study are twofold: (1) the addition of a new method to the research methodology toolbox in construction engineering and management; and (2) the generation of design insights to develop IVR prototypes for research in construction engineering and management, and preliminary evidence for its ecological validity. [ABSTRACT FROM AUTHOR]

Steel through-truss is a very common configuration for railroad and highway bridges. There is a large number of such spans in surface transportation infrastructure worldwide, especially in railway systems. In design and evaluation, these spans' in- and out-of-plane bending have been either omitted or approximated. A fuller understanding of this effect will be able to assist in reliably designing and assessing these structures for longevity and/or increasing allowable service load to facilitate economic developments. A full scale load test is performed in this paper on five such bridges of the Canadian National Railway (CN) using train load. The main truss elements prone to in- and out-of-plane bending are identified and strain-gauged including the hanger (L1U1 or L'1U'1). Out-of-plane bending is seen to produce more significant flexural stress than in-plane bending. Three-dimensional (3D) numerical simulation is also verified by physical tests and covers other uninstrumented members of the tested spans. These results are used to evaluate the accuracy of a new and simplifying two-dimensional (2D) analysis method for the most significantly bent vertical hanger out-of-plane. The 2D method is shown to capture a significant portion of the bending but still underestimate flexural stress. An empirical and hybrid approach is therefore developed and recommended to address the inadequately accounted out-of-plane bending for routine practice of design and evaluation. It is needed when resources for detailed 3D analysis are not readily available, and/or when a quick and reliable method is needed, e.g., for verification or calibration of another method. These results are also useful for stress range estimation for fatigue analysis, although fatigue is not a concern to these bridges and is therefore not specifically addressed in this paper. CN has adopted the recommended method and the other research findings in load-rating their existing through-truss bridges. [ABSTRACT FROM AUTHOR]

The author comments on the article "Rapid Evaluations of Anticlogging Performance of Drip Emitters by Laboratorial Short-Cycle Tests." He explains that the recommended evaluation process offers an opportunity to determine the clogging status of some drip emitters concerning the critical level of clogging. He considers the reduction of the plugging effect. He provides the values of clogging rate and modified uniformity coefficient for drip emitters.

In an effort to assist transportation professionals with the evaluation of wider economic benefits (WEB) of highway improvements, this paper provides important insights into the open-source AASHTO EconWorks wider economic benefits analysis tools using three case studies located in Indiana. The paper makes a significant contribution to the state of practice by providing an in-depth discussion of the lessons learned during the Federal Highway Administration (FHWA) implementation assistance program in Indiana. The paper briefly presents the theoretical background related to the development of the tools and explains data needs and sources. The discussion of the case studies primarily focuses on the sensitivity of the tools' results to critical input parameters (such as volume to capacity ratio and productivity elasticity), which has not been addressed in previous studies. Lastly, the paper elaborates on the applicability and limitations of the tools, and also discusses their potential integration into an agency's decision-making process. The inferences from this case study can be useful for state departments of transportation (DOTs), metropolitan planning organizations (MPOs), and other organizations interested in quantifying the potential productivity gains associated with planned or future highway projects. [ABSTRACT FROM AUTHOR]

Many decisions are based on more than one criterion, judged by more than a single evaluator. Multievaluator multicriterion (MEMC) decision making can be controversial if bias or uncertainty find their way into the final decision. In fact, both public and private organizations have recently faced challenges when making decisions. In a previous study, the authors of this paper developed a multievaluator decision making model that reduces the effect of possible uncertainty resulting from an evaluator's insufficient expertise in a particular criterion. This paper builds on the previous model by also correcting for any possible evaluator favoritism or bias. It presents a more comprehensive mathematical model that supports MEMC decisions and protects decision makers and their agencies from potential criticism. Testing of the model shows that it performs better than the simple averaging method on 100% of the simulations. [ABSTRACT FROM AUTHOR]

When fire breaks out in a building, smoke poses the most serious threat to the inhabitants. Hence, the fireproof quality of a building interior decorative material is a major concern of the fire fighting and safety of the whole building, especially when recycled materials are applied as interior components of a fireproof building. Current architectural technology regulations require that fireproof materials be used in buildings; the Bureau of Standards, Metrology, and Inspection, Taiwan provides a set of examination procedures. However, the fireproof quality of building interior decorative materials has not been specified, and there is no model that is simple but effective for evaluating the material fireproof quality. In this paper, the specifications published by the Bureau in CNS 6532 A3113, and the define, measurement, analysis, and do model are applied to define, evaluate, and analyze the fireproof performance. The results can be referenced by building supplier for selecting appropriate materials. In this method, the smoking coefficient (CA), fireproof index (XerrU), fireproof stability index (SerrU), fireproof quality index (CFU), and unbiased estimation coefficient (bn-1) are first specified prior to defining the procedure for evaluating the quality performance. After the evaluation is completed, the-larger-the-better and the-smaller-the-better performance matrices along with the quality performance evaluation model are implemented as evaluation tools to determine the improvement needs, or adopt a procurement policy. The definition, evaluation, analysis, and decision making model proposed in this paper can be implemented by industries to evaluate and analyze the fireproof quality of building material and to identify the best suppliers and companies that need guidance and assistance. This will allow the industry to effectively elevate the product quality and competitiveness such that the enterprise management can be strengthened. [ABSTRACT FROM AUTHOR]

This paper aims at presenting a job performance evaluation process for construction companies. Human resource is a core economic asset. Organizations are responsible for helping their employees work at their optimal level. Job performance evaluations become an essential organizational activity, which can sustain employee performance. Existing literature has suggested that the construction industry does not pay attention to the importance of job performance evaluation. This paper presents the use of the analytic network process (ANP) to assign weights to a set of job performance criteria. It also describes a process for job performance evaluation. An example is demonstrated to illustrate how to construct the supermatrix for ANP. [ABSTRACT FROM AUTHOR]

This paper proposes a novel concept, stop-line setback (SLSB), aimed at enhancing the capacity of signalized roundabouts and solving the problem of unbalanced flow patterns. This method is believed to avoid wasting acceptable time gaps and therefore increase the capacity of the approach with SLSB. However, to the best of the authors' knowledge, no analytical work and little empirical work has yet explored the impact of SLSB. To bridge this gap, the phasing scheme and an adaptive control algorithm are developed for the roundabout with SLSB. Case studies are conducted under different traffic demands to evaluate the method. The findings show that (1) in peak hours the SLSB method is useful to improve the operational performance of the signalized roundabout and solve the problem of unbalanced flow patterns; (2) the right-turning vehicle volume is the critical factor that influences the benefits of the SLSB method; and (3) the phasing scheme and adaptive signal control algorithm developed in this paper are suitable to signalized roundabouts with distances of SLSB. Based on the aforementioned findings, it is recommended that the SLSB method be applied to one or two approaches with heavier traffic loads but not all approaches, which is believed to increase the capacity and reduce the average vehicle delay of the roundabout. [ABSTRACT FROM AUTHOR]

Land expansion and population growth are the most important factors for urban development in the rapid urbanization stage. Intensive land use is a key goal of urban sustainable development. Therefore, to promote intensive land use, local governments should take the scientific evaluation of the relationship between urban land and population as the basis and make policies cautiously. Thus, it is vital to adopt evaluation methods that are sensitive to intensive land use. However, this topic has received insufficient attention in the literature. Addressing this gap, this study (1) proposes a modified method to evaluate the relationship between land expansion and population growth, (2) compares the results of three evaluation methods, and (3) compares the relationship between evaluation results and urban construction land area per capita (UCAP) using UCAP as an indicator of intensive land use. Our findings indicate that existing evaluation methods do not adequately reflect the state and trend of intensive land use and that our modified model significantly improves the sensitivity to intensive land use. Additionally, this paper provides policy suggestions based on a quantitative evaluation of the relationship between urban land expansion and urban population growth. These conclusions provide a basis for formulating planning strategies to promote the intensive use of land in cities in the stage of rapid development. [ABSTRACT FROM AUTHOR]

Public participation as an alternative paradigm in planning theory is consequently a key challenge in planning practice regarding interactive and collaborative versus rational and top-down decision-making approaches. Hence, this paper aims to define this concept theoretically and then to evaluate it practically. Based on the relevant views and research, public participation has been considered through three main dimensions of "inclusiveness and incentive structures," "information exchange and provision of lay knowledge," and "sense of ownership and influence on decision-making." This threefold conceptualization has also been further explored by 10 subdimensions or measures to explain precisely the specific aspects of community participation. "Transparency and accessibility," "fairness or equal contribution," "effectiveness and efficiency," and "negotiation" are the most significant subdimensions. Thus, the concept of public participation has been evaluated in the Oudlajan market (Bazarcheh) in Tehran, where a supposedly participatory revitalization project has been implemented. This evaluation relies on the views of 117 market traders as respondents, using the analytical hierarchy process method. Accordingly, the overall status of the public participation in the Oudlajan project with a score of 2.56 based on a 5-point Likert-type scale is evaluated as between low and average. This finding implies that while the Oudlajan Market Revitalization Plan may seem participatory, it has serious shortcomings, especially according to the actual affected community or group. [ABSTRACT FROM AUTHOR]

The use of short-term load data to extrapolate or project remote future maximum load has been practiced in structural design code development and/or calibration. However, this approach has not been adequately evaluated or validated because of the absence of long-term data, which is important for the structures' safety governed by these codes. In this paper, the application of such extrapolations to highway bridge design is studied by taking advantage of available long-term truck weight data obtained from the weigh-in-motion technique. A new extrapolation method is proposed from the understanding of the importance of the load probability distribution's high tail. This approach significantly reduces the mathematical length of the extrapolation/projection and thus increases its reliability. Also presented in this paper are application examples. In addition, the extrapolation process proposed is evaluated with quantitative indexes. The application of a temporal extrapolation/projection can now be evaluated by using these indexes for its reliability and appropriateness. [ABSTRACT FROM AUTHOR]

In-place nondestructive simulation evaluation of the remaining bending strength of wooden utility poles is vital to the continued and successful operation of the poles, viability of the electrical transmission and delivery system, and reduction of system disruption potential. A methodology for nondestructively assessing the strength of in-place wood utility poles was developed and is proposed in this paper. Because of the nonhomogeneous and anisotropic nature of wood and the variability of in-place utility poles, a deterministic approach does not seem feasible. The proposed method combines multiple variables to statistically predict the breaking strength, or modulus of rupture, of wood poles. The full-scale testing methodology was tested on real life poles. Results from in-field simulation tests were correlated to data from failure testing of the full-scale poles. The proposed static bending approach is quite accurate, utilizing a device that applies a horizontal force on an in-place utility pole and measures the resulting deflection. The slope of the force-deflection curve and the pole moment of inertia from a regression analysis correlate well to the breaking strength of the poles. Additionally, a method for measuring and adjusting for the tilt of the utility pole under test was determined. Full-scale field simulated testing and break testing data that provide significant insight into nondestructive wood pole testing are provided in this paper. Recommendations for increasing the validity of the proposed model with additional test data, together with implementation of additional relevant parameters, are made. [ABSTRACT FROM AUTHOR]

The Federal Occupational Safety and Health Administration (OSHA) maintains standards (Standards) that define structural requirements for elements that support suspended scaffolds and fall arrest lanyards when this equipment is used to access facades and other elevated portions of buildings. The Standards are available online at www.osha.gov. Ensuring that applicable requirements are met is the responsibility of a qualified person—typically a professional engineer. However, navigating and applying the OSHA structural provisions can be difficult primarily because relevant requirements are not located in a single document, structural requirements vary for different uses, and structural requirements are not always written in a manner consistent with typical structural engineering practice. The rational application of key OSHA structural provisions when designing suspended scaffold support elements and lifeline anchorages is the subject of a companion paper, “Designing Suspended Scaffold Structural Support Elements and Lifeline Anchorages in Conformance with Federal OSHA Requirements,” which is included in this publication. The objective of this paper is to promote the rational application of sound engineering principles when certifying the adequacy of existing elements and their compliance with OSHA Standards. Unfortunately, certain trends and recent developments in the facade access equipment industry have made proper certification more difficult than it needs to be; irrational approaches and conclusions are, at times, actually encouraged by industry groups. [ABSTRACT FROM AUTHOR]

The equation for calculating the normal modes of a uniform beam under transverse free vibration involves the hyperbolic sine and cosine functions. These functions are exponential growing without bound. Tables for the natural frequencies and the corresponding normal modes are available for the numerical evaluation up to the 16th mode. For modes higher than the 16th, the accuracy of the numerical evaluation will be lost due to the round-off errors in the floating-point math imposed by the digital computers. Also, it is found that the functions of beam modes commonly presented in the structural dynamics books are not suitable for numerical evaluation. In this paper, these functions are rearranged and expressed in a different form. With these new equations, one can calculate the normal modes accurately up to at least the 100th mode. Mike’s Arbitrary Precision Math, an arbitrary precision math library, is used in the paper to verify the accuracy. [ABSTRACT FROM AUTHOR]

This paper raises the issue of “soft” considerations in the selection of equipment for building construction projects. The paper aims at increasing the awareness: (1) to the nature, variety, and richness of soft factors; (2) to their significant role and potential impact on the outcome of decision making; and (3) to the inherent difficulty of evaluating them and integrating them within a comprehensive selection process. Existing state-of-the-art equipment selection models were analyzed and found to be inadequate in terms of both considering soft factors and providing mechanisms for their systematic evaluation. Six cases of large-size, complex construction projects were investigated to obtain an extensive list of typical soft factors. This investigation revealed that the consideration of soft factors in current practices is essentially unstructured and is not integrated within the selection process in a systematic manner. A desirable selection process is outlined that generally responds to the needs identified in the study. The proposition of a specific method for the quantitative treatment of soft factors and their tradeoff with cost factors is the subject of another paper. [ABSTRACT FROM AUTHOR]

Development of new burner technology is common practice nowadays. Standardized test codes are available to conduct tests to determine operating characteristics and thermal performance of different parts of steam generating units. This paper describes the results of testing performed to evaluate thermal efficiency of a 74.5 kW fire-tube steam generator fired with a new premixed flame burner in comparison to a typical standard-retrofit diffusion flame burner system. Two premixed flame burners sized at 7.6 and 10.1 cm were tested. Testing was performed in accordance with the ASME PTC 4.1 Power Test Code. The evaluation was conducted in the range of small- to mid-sized, natural gas-fired applications, from 1.06 to 2.64×106 kJ/h. The environmental nitrogen oxide (NOx) emissions performance was also compared for both burner technologies. The results of this evaluation indicate that firing the test boiler with the 7.6 cm new burner slightly improves unit thermal efficiency by 4.0–3.3% for a unit load ranging from approximately 1.06 to 1.79×106 kJ/h, respectively. Operation with the 10.1 cm new burner improves the thermal efficiency by approximately 1.6% at 2.32×106 kJ/h. The uncertainty in the measurements used in the efficiency calculations should account for approximately ±1.5% uncertainty in the reported gross efficiency. Reductions in NOx emissions of the order of 10% resulted from operation with the new premixed flame burners. [ABSTRACT FROM AUTHOR]

Engineering education is challenged to usher in new approaches to preparing its students for their professional careers. Many blue-ribbon committees call for systematic modifications in research universities to clear the path for cross-disciplinary learning communities. In this context, the paper investigates the effect of student ratings as a measure of teaching effectiveness. One survey found that engineering sophomores perceive active student-centered teaching methods as greatly ineffective, while a second survey highlighted that lecture-based teaching underpins student rating forms used at U.S. research universities. With the goal of aligning teaching objectives, learning outcomes, and the criteria for evaluating teaching, a student rating form is presented. The scales of the multidimensional construct are based on the most up-to-date understanding of effective pedagogy, the new American Accreditation Board for Engineering and Technology criteria, and a view of the future of our profession. The importance of this paper lies in its science-based proposal underlying a call for the establishment of a coalition to validate a constructive approach to further teaching performance in the field of construction engineering and management. [ABSTRACT FROM AUTHOR]

Real-world experiments in which some experimental units (e.g., people or roadway sites or vehicles) are randomized to treatment and others to no treatment are increasingly regarded as practicable and desirable. This is the case for complex educational and social welfare interventions as well as for therapeutic drug trials. The present paper discusses the relevance of such experiments to transport and transport safety research. When compared with the more common designs of research, both the advantages and the disadvantages may seem substantial, and decisions will require good judgment. Drawing lessons from medical and social welfare research, the paper aims to be a resource when the relative merits of randomized experimentation and other methods are being debated. [ABSTRACT FROM AUTHOR]

This paper discusses advances in evaluation and health monitoring of cable-stayed bridges and available methods. Bridge engineers and highway administrators in the United States are gradually becoming more comfortable with cable-stayed bridges, and the past few years have seen a significant increase in construction of these elegant bridges in many parts of this great nation. In the last decade, several investigations have been directed to condition assessment of cable-stayed bridges and contributed extensively to advances in construction, design, and health monitoring of this type of structures. Results of these investigations have helped toward formation of a unified approach for in-service evaluation and problem solving of these aesthetic structures. This paper describes this approach with reference to sources for more detailed information. Additionally, discussed in this paper are a series of methods developed or tailored for evaluation of these unique structures. The paper also reviews the typical problems observed in the course of field evaluations for in-service cable-stayed bridges. [ABSTRACT FROM AUTHOR]

Benchmarking is a systematic process of measuring and comparing an organization’s performance against that of other similar organizations in key business activities. The lessons learned from other companies can be used to establish improvement targets and to promote changes in the organization. The benchmarking process can create a fertile ground for ideas, but only in a receptive environment; companies that share good practices and compare their performance against others benefit most. Recently, industry groups in several different countries have initiated benchmarking programs focused mainly on construction performance measures. This paper describes the scope of these initiatives and discusses the lessons learned and improvement opportunities that were identified in their design and implementation. This investigation is focused on four initiatives, carried out in Brazil, Chile, the United Kingdom, and the United States. This paper concludes by recommending some further directions on this research topic. [ABSTRACT FROM AUTHOR]

This paper discusses advances in evaluation, health monitoring, and rehabilitation of cable-stayed bridges, and available methods. In the last 2 decades, the writer has contributed extensively to advances in cable-stayed bridge construction, design, and health monitoring. Information gathered from evaluation of the strength and reliability of dozens of stay cable systems worldwide, and health monitoring and inspection of more than 12 cable-stayed bridges in the United States and abroad, have discovered problem conditions that seem to be consistent across many types of cable-stayed bridges and stay cable designs, and have helped toward formation and evolvement of a unified approach for in-service evaluation and problem solving of these aesthetic structures. A case study related to evaluation and rehabilitation of the Luling Bridge in Louisiana, for which the new approach has been implemented almost entirely, is also described. The bridge evaluation process, and cable replacement design and its implementation, contain unique aspects and are the first attempted in North America. The cable replacement design accommodated an extraordinary construction sequence to address constraints on space and traffic flow. Temporary cables minimized stress variation and allowed for the live load without restriction. The new cable system allows individual strand installation and tensioning, and is expected to facilitate future inspections and replacement. [ABSTRACT FROM AUTHOR]

A system dynamics (SD) model was developed to identify the best road strategies for network-level maintenance and rehabilitation, considering technical, environmental, and economic grounds. This SD model uses triangulated research methods and data [e.g., interviews, policy analyses, and the VIZIR Pavement Distress Assessment Method (VPDAM)] to determine and allocate maintenance budgets in specific environmental and operational conditions. The system is tested via a case study at the Tunisian Radès Road Port (RRP). Baseline analyses of the simulation show the networked effects of key factors, including increased greenhouse gas (GHG) emissions, rehabilitation deficits, and climate change with reduced average pavement life. The SD model is calibrated and validated using data from RRP rehabilitation operations from 2020 until 2040. The model is coupled with an optimization module that recommends three optimal pavement solutions for the RRP and three pavement management systems (PMS) policies for improved sustainability. The model is based on sound technical principles, enhancing road function, sustainability, and cost savings. These findings contribute to the literature in PMS, SD modeling, sustainable development, and engineering management. [ABSTRACT FROM AUTHOR]

Cement-stabilized pavement layers are subject to sulfate attack (SA) in sulfate-abundant regions due to internal expansion–induced damage throughout its expected service life. SA is a coupled physical-chemical-mechanical damage process for cementitious materials involving complicated chemical reactions between sulfate and components of cement composite. SA contains intricate interactions among porous media, moisture transport, and heat transfer. Engineering mechanics has been used to explain the failure process of the internal expansion caused by this coupled physical-chemical ingress phenomenon. Existing studies have considered only heat transfer or moisture content–dependent modeling. The literature lacks a comprehensive model that considers coupled interaction of temperature and humidity upon sulfate ingression. Thus, a chemomechanical (CM) model has been developed for capturing the true failure process of cement-stabilized pavement subgrades under SA. In this paper, a set of governing equations are developed, and a unique expression for a moisture-dependent and heat-dependent sulfate diffusion coefficient is proposed. Consequently, the equations are solved using the finite-element method. The results conform well with experimental results. The model has been validated to be accurate enough compared with previously implemented models. It is capable of evaluating and predicting SA-induced expansive failure in unsaturated cement-stabilized pavements. Two different models were combined to estimate the mechanical behavior of cement-stabilized subgrades subject to SA. Finally, the Drucker-Prager (DP) failure criterion was used for determining the damage zone. [ABSTRACT FROM AUTHOR]

This paper describes the development of Evaluation of Pavement Condition Model software (EPCM), which consists of three main elements. The first element deals with a road network definition to create a database for each road in the network to make future predictions of pavement condition. The second element evaluates the present status of asphalt pavement depending on the type, severity, and extent of distress, and then calculates the value of a pavement condition index. For each value there is certain pavement condition requiring one type of maintenance activity. The third element deals with prediction of the pavement condition in future. This element cannot be applied in Iraq now because there are no historical data for each road in the network, but after applying this model and saving the information about each road, this will become possible after drawing a curve for each asphalt pavement. The written software was applied to a case study of local road in Abo-Ghreeb city in Baghdad with a length of 1.45 km and a width of 8 m. The result of this application was that road required an asphalt overlay. According to the Abo-Ghreeb municipality, the required maintenance activity for this road was resurfacing, which is the common maintenance method in Iraq. This is different because of the independency on a fixed criterion to select a maintenance method. [ABSTRACT FROM AUTHOR]

In this paper, current and proposed methodologies for assessing the robustness and redundancy of bridge structures are discussed and an overview of the latest advances in research is presented along with proposals for implementation in bridge design and evaluation codes. In particular, European and North American standard codes and guidelines, including the Eurocode, AASHTO, and the Canadian Standards Association (CSA), as well as some national European codes and related guidelines, are compared. Research projects, including those of the European Cooperation of Science and Technology (COST) and the U.S. National Cooperative Highway Research Program (NCHRP), represent key links between research activities and the need for implementing concepts of structural redundancy and robustness into the codes. The activities undertaken by COST and NCHRP constitute attempts to synthetize, simplify, and implement theoretical concepts that have been discussed over many years. This review shows that the U.S. approach concentrates on developing tools and criteria for the numerical evaluation of the capability of a bridge structure to continue to carry load after the failure of a member, whereas the European approach, still in a more theoretical phase, lacks specific guidelines for bridges and uses available building recommendations. This paper also presents a critical assessment of the state of the art and argues that criteria implementable in future generations of bridge codes should be based on quantifiable measures of risk, which is a subject still in its very early stages of development. [ABSTRACT FROM AUTHOR]

The interface bond strength between carbon fiber-reinforced polymer (CFRP) layers and concrete is a crucial metric for determining the mechanical properties of CFRP-reinforced concrete. This bond strength is essential for evaluating CFRP-reinforced concrete's performance and ensuring the materials' structural integrity. A database was established using the experimental data in the literature to evaluate the interface bond strength. This database comprised 360 groups of different conditions test results of CFRP-reinforced concrete, which were used to create a prediction model using an artificial neural network. The database was randomly divided into two data sets: 310 groups were used for training the neural network model and 50 for simulated prediction. A three-layer artificial neural network model was trained using the backpropagation algorithm, which is widely used in artificial neural networks. The model's input layer considered seven parameters, including the type of CFRP layer, surface form, CFRP layer thickness, anchorage length, failure mode, concrete compressive strength, and normalized concrete cover thickness. These parameters were selected based on their known influence on the interface bond strength between the CFRP layers and concrete. The output layer of the model represented the interface bond strength between the CFRP layers and concrete. The model's results indicated that the backpropagation (BP) neural network model had strong capability of prediction and generalization. The predicting error was minimal, a crucial aspect of the model's accuracy. Further, this approach allows for integrating many factors that influence the interface bond strength between the CFRP layers and concrete, providing accurate predictions of the bond strength. It can be used as a valuable tool for evaluating the performance of CFRP-reinforced concrete. This research develops an accurate method to predict the bond strength between CFRP layers and concrete using artificial neural networks. A strong bond is crucial for the structural integrity of concrete reinforced with CFRP. The neural network model considers factors like the type and thickness of CFRP used, how the concrete surface is prepared, and the concrete's strength. Engineers can use this neural network tool to evaluate how well CFRP will reinforce specific concrete mixtures and structures before construction. This allows structures to be designed and built with optimal, cost-effective use of CFRP to reinforce concrete in applications like bridges and buildings. The neural network approach integrates many technological and material factors into one predictive model, providing a useful evaluation method for the construction industry. [ABSTRACT FROM AUTHOR]

Previous studies of models for evacuation routing usually divide the space into multiple interlinked zones. However, for public buildings that are characterized by a more complicated spatial composition, it may be harder to clearly and objectively define the margins for each zone. This paper proposes an approach that determines the most appropriate guidance locations and assembles them into an efficient guiding network. This allows evacuation routes to be constructed based on the links between starting points, guiding nodes, and terminal points. This approach avoids the difficulty of dividing a space into multiple zones and conforms more to real-life evacuation behavior. This paper also proposes an integrated model that applies simulation to estimate the evacuation time and ant colony optimization algorithms to search for an evacuation routing plan and a near-optimal guiding solution. The feasibility of the model is evaluated through a case of one floor in a hospital building. The results indicate that the model provides valuable suggestions for evacuation planning and offers practical support for the design of an evacuation guidance system. [ABSTRACT FROM AUTHOR]

This paper presents the field evaluation of a damaged noncomposite steel girder bridge that is part of the interstate highway system in Vermont. This bridge is typical of late 1960s construction and spans over a two-lane state highway near the town of Weathersfield, Vermont. The superstructure contains three-span continuous girders supported on abutments at the ends and on RC multicolumn interior bents. Strains were measured during live-load testing that was conducted to better understand the bridge behavior. The field results were compared with results from finite-element models created using common engineering assumptions. In addition, the load-distribution characteristics of girders that were damaged by an overheight truck traveling on the state highway under the bridge were evaluated. The results indicate that alternate load paths were developed within the bridge superstructure as a result of damage from the truck impact. For the loading magnitude applied during the load tests, evidence of composite action was observed and participation of curbs on the response of the bridge was noticed. Bridge skew and partial restraint generated at the supports also contributed to differences in the observed and calculated responses. These nondestructive load testing results were used to provide confidence on the load-carrying capacity of the bridge and to avoid costly bridge closures and detours. [ABSTRACT FROM AUTHOR]

This paper seeks to examine the concrete contribution to shear strength and determine the inclination of the compressive strut within the variable truss model for slender RC shear-critical beams with stirrups. Using the modified compression field theory in place of the conventional statistical regression of experimental data, the expression for the concrete contribution to shear strength was derived, and the inclination of compressive struts was determined. A simplified explicit expression for shear strength was then provided, with which shear strength can be calculated without extensive iterative computations. This method was then verified using the available experimental data of 209 RC rectangular beams with stirrups and compared with the current methods from the American Concrete Institute and the Canadian Standards Association. The theoretical results are shown to be consistent with the experimentally observed behavior of shear-critical RC beams. [ABSTRACT FROM AUTHOR]

This paper is a transitory decadal overview capturing the current research and technology accomplishments that are being developed by the Optical Instrumentation and Nondestructive Evaluation (NDE) Branch at the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC). The emphasis is on the latest GRC research and technology advances with a brief discussion of the history and technical background of optical instrumentation since the 1940s, NDE sciences and methods since the 1970s, fiber optics since the 1980s, space-qualified instrumentation since the 1990s, and propulsion health monitoring since the beginning of the current century. This paper also identifies and describes recent and future technical directions based on/guided by current NASA strategic and GRC and NASA project implementation plans. [ABSTRACT FROM AUTHOR]

The objective of this research is a preliminary examination of metro rail network extensiveness versus the city's needs, aiming to assist the estimation of the adequacy of a metro network. This paper concentrated on comparing mature metro systems in several large European cities based on a selection of indicators relating metro network characteristics, i.e., length and number of stations, to city characteristics, e.g., population and density. A methodology exploiting these macroscopic characteristics in a strategic planning context was developed, and a combination of related indicators is proposed. This methodology is applied for the estimation of the degree of adequacy of the current Athens, Greece metro network in relation to the city's needs. Findings indicate that the Athens metro network cannot be yet characterized as adequate, and specific proposals are made in terms of future network extensions. These proposals served as the initial reference point in a more sophisticated planning process for Athens metro system future development that outlined a future metro network of eight lines, 220 km, and 200 stations, setting in this way long-term targets for the main city transport infrastructure in order to mobilize the necessary resources and avoid infrastructure development conflicts. [ABSTRACT FROM AUTHOR]

Previous studies of models for evacuation routing usually divide the space into multiple interlinked zones. However, for public buildings that are characterized by a more complicated spatial composition, it may be harder to clearly and objectively define the margins for each zone. This paper proposes an approach that determines the most appropriate guidance locations and assembles them into an efficient guiding network. This allows evacuation routes to be constructed based on the links between starting points, guiding nodes, and terminal points. This approach avoids the difficulty of dividing a space into multiple zones and conforms more to real-life evacuation behavior. This paper also proposes an integrated model that applies simulation to estimate the evacuation time and ant colony optimization algorithms to search for an evacuation routing plan and a near-optimal guiding solution. The feasibility of the model is evaluated through a case of one floor in a hospital building. The results indicate that the model provides valuable suggestions for evacuation planning and offers practical support for the design of an evacuation guidance system. [ABSTRACT FROM AUTHOR]

People are generally very sensitive to unexpected vibrations. Very small levels of building floor movements due to activities such as walking can become annoying to occupants. Accurate prediction, evaluation, and assessment of vibrations can greatly assist engineers and architects to design cost-effective building structures without such problems. In an attempt to clarify some of the issues related to this common serviceability problem, this paper presents a study of the various parameters used for the evaluation and assessment of building vibrations. Provisions of several current standards and design guides commonly used in North America and U.K. to evaluate and assess building vibrations as related to human perception and comfort are reviewed. These provisions are then applied using the vibrations measured during a number of walking tests conducted on a large cantilevered office building floor. Based on the results of this study, it is concluded that the vibration dose value (VDV) recommended by some standards and design guides provides a consistent and reasonable method of evaluation of building floor vibrations. In addition, new relationships between VDV, peak frequency-weighted acceleration, and crest factor are established to estimate the VDV. [ABSTRACT FROM AUTHOR]

In the Mechanistic Empirical Pavement Design Guide (MEPDG), rather than producing a quantitative overall evaluation index, several performance measures are used to separately evaluate the pavement performance condition for rehabilitation design. Due to the characteristics of information on parameters being partially known during the evaluation process, there exist several limitations of the current evaluation methods. In this paper a gray clustering-based methodology is proposed to comprehensively evaluate existing pavements following the MEPDG framework. Gray clustering method is one pillar part of the gray system theory, which was proposed in the 1980s to solve problems with partially known information. The performance criteria used in this study are selected from those defined in MEPDG. The analysis data sets are obtained from the long-term pavement performance (LTPP) database for three types of pavements: flexible pavement, jointed plain concrete pavement, and continuous reinforced concrete pavement. Many LTPP pavement sections are evaluated using the proposed methodology and comparisons are made between gray clustering-based method and extension theory-based approach. It is shown that the proposed gray clustering-based method is able to quantify pavement performance and is suitable to be used as a practical pavement evaluation tool for highway agencies. [ABSTRACT FROM AUTHOR]

Government agencies and other organizations responsive to a diverse constituency face enormous challenges in identifying priority sites for relocation, expansion, or new development. Of paramount importance is establishing transparent decision processes that reach accountable, defensible, and wise outcomes. Unfortunately, documented examples of successful approaches to evaluation, prioritization, and site selection are scarce. The purpose of this paper is to both offer a descriptive case study and an intellectually rigorous, fundamentally practical “best practice” approach for identifying priority sites. By employing value-focused thinking and decision analysis techniques to a complex site selection problem, we present a way to address common challenges such as potential technical and nontechnical knowledge conflicts, distinguishing between “facts” and “values,” incorporating uncertainties, generating criteria weights, making trade-offs and building consensus across interests. Our approach is contextualized in a Canadian government case study of relocating a $300 million dollar facility. [ABSTRACT FROM AUTHOR]

The alliance concept is similar to the design build project delivery system. However, it is denoted by a special form of partnership between the owner and the design-build team, where the owner is very involved in the project. This type of delivery systems is gaining popularity as many infrastructure projects require the owner to order materials ahead of time, before engaging the design-build team in the project. As in design-build, the selection of the engineer-procure-construct team depends not only on the price but also on qualitative factors. This paper lays out the framework that facilitates selecting the best alliance team for a project by quantifying the evaluation factors and combining them into a single score. Using a Monte Carlo simulation and varying all the factors relevant to the decision problem can reveal biases present in the evaluation to assist in making the best possible decision. A case study dealing with a large utility project illustrates this methodology. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive overview of recent developments in the performance evaluation and flexural response of existing bridges from fundamental concepts to advanced topics. The focus is particularly on the structural evaluation to enhance the quality assessment of constructed bridge superstructures, taking into account a synthesis of the most important contributions to the flexural behavior of existing bridges, such as dynamic responses and lateral load distributions. This state-of-the-art paper provides a critical review of published literature and existing assessment methodologies in conjunction with corresponding analysis techniques, including technical comments on the code provisions. Detailed descriptions of the important parameters influencing flexural responses of existing bridges are discussed, such as the geometric effect, loading configuration, present condition of a bridge, and contribution of secondary structural elements. The review also includes the investigation methodologies, namely, the diagnostic and proof load tests. Finally, the current research needs to further advance the performance evaluation technologies for existing bridge superstructures are recommended. [ABSTRACT FROM AUTHOR]

A typical irrigation scheduling problem is one of preparing a schedule to service a group of outlets which may be serviced simultaneously. This problem has an analogy with the classical earliness/tardiness problem in operations research. In previously published work an integer program was used to solve this problem, however such scheduling problems belong to a class of combinatorial problems known to be computationally demanding (N-P hard). This is widely reported in operations research. Hence integer programs can only be used to solve relatively small problems usually in a research environment where considerable computational resources and time can be allocated to solve a single schedule. For practical applications metaheuristics such as genetic algorithms, simulated annealing, or tabu search methods need to be used. However as reported in the literature, these need to be formulated carefully and tested thoroughly. This paper demonstrates the importance of robust testing of one such genetic algorithm formulated to solve the irrigation scheduling problem with simultaneous outlets serviced against an integer program formulated to solve the same problem. [ABSTRACT FROM AUTHOR]

As more manufactured stormwater treatment devices enter the market, stormwater managers are searching for effective and rapid methods for evaluating device performance. Many agencies require vendors to test full-scale versions of their devices under controlled conditions. The most common parameter used to document performance is suspended solids for several reasons: (1) many pollutants attach to solids; (2) a solids simulant is relatively easy to generate; and (3) solids are comparatively easy and inexpensive to quantify. However, a controversy still exists in the profession and some regulatory agencies as to whether total suspended solids (TSS) or suspended sediment concentration (SSC), or both, should be measured. This paper focuses on the comparability of the two methods/protocols used for sample solids analysis, including lessons learned during recent evaluations of two manufactured treatment devices. Analysis of 215 sample pairs (where both TSS and SSC were measured on aliquots of the same sample) showed that statistically the TSS measured using the wide-bore pipet method and SSC results were indistinguishable from one another and from the original simulant mixture. [ABSTRACT FROM AUTHOR]

The objective of this study is to measure the effectiveness of three commonly used changeable message sign (CMS) messages in reducing vehicular speeds and variances in highway work zones. This paper presents the results of a field study conducted on Interstate-90 in western New York State to evaluate the use of three different types of messages displayed on a CMS, as a speed control measure. The study included speed measurements of nearly 180,000 vehicles. The three types of CMS messages tested were: (1) RIGHT|LANE|CLOSED∼KEEP|LEFT; (2) WORK ZONE|MAX SPEED|45 MPH∼BE|PREPARED|TO STOP; and (3) LEFT|LANE|CLOSED∼KEEP|RIGHT. Of the three CMS messages tested, the CMS message stating “WORK ZONE|MAX SPEED|45 MPH∼BE|PREPARED|TO STOP” proved the most effective, significantly reducing vehicle speeds by 3.3–6.7 mi/h(5.3–10.8 km/h). The other two CMS messages were not as effective. The standard deviation of speed for the CMS message: WORK ZONE|MAX SPEED|45 MPH∼BE|PREPARED|TO STOP increased by 1.1–1.7 mi/h(1.8–2.7 km/h) in the driving lane and 0.2–2.0 mi/h(0.3–3.2 km/h) in the passing lane. The speed variances for the other two CMS messages ranged from -2.00 to 1.13 mi/h (from -3.23 km/h to 1.83 km/h). [ABSTRACT FROM AUTHOR]

This paper presents a hybrid framework that integrates value analysis and decision making for eliciting and evaluating design alternatives. Value analysis approach relies on the integration of the functional analysis through the systematic use of the functional analysis system technique and quality function deployment. This value analysis methodology enables customer requirements to be linked to specific design alternatives during the project design stage. The degree of project complexity will affect the number of design alternatives to be evaluated. As such, the data envelopment analysis (DEA) is incorporated as a decision support tool to evaluate the degree to which each design alternative satisfies the customer requirements. DEA is used to calculate a customer requirement efficiency index for each alternative. This index is a measure of how well a particular alternative achieves the requirements taking into account its overall cost. The framework was successfully used on a high-tech research facility construction project. [ABSTRACT FROM AUTHOR]

The need arises to equip engineering students with a wider horizon of concepts in terms of environmental, economic, and social attributes, for decision making of sensitive to sustainability issues. Pedagogic frameworks have to address a multidisciplinary analysis of sustainability. This paper addresses the rationale behind the recent integration of sustainability concepts into an undergraduate civil engineering curriculum in Hong Kong. Incentives and barriers for implementation of the curriculum are addressed. A team-based design project with a problem-based learning approach is highlighted. The initial results of stakeholder evaluations suggested that multidisciplinary skills developed during the learning process might contribute significantly to pertinent knowledge on sustainability. [ABSTRACT FROM AUTHOR]

Treatment selection bias leads to an inaccurate estimation of treatment effects as applied to specific sites or problem locations. Treatment selection bias is a major source of inconsistency in the results obtained from conventional before and after and cross-sectional models. One of the major expressions of treatment selection bias concerns the use of collision occurrence data in justifying intervention. For example, in highway safety field, a treatment is often introduced at a given site based on its high collision experience. Under normal conditions we would expect these collision numbers to return to a lower long term expected value, regardless of intervention. For treated sites, conventional observational models ascribe this reduction in collisions to the given treatment. This results in an overestimation of treatment effect. In this paper, a propensity score model is introduced that deals explicitly with treatment selection bias. The model is applied to Canadian highway–railway grade crossings data to estimate reductions in collision subject to upgrades in warning devices. The results of the propensity score model are compared for similar types of treatments to a number of before and after and cross-sectional models for both U.S. and Canadian data. The propensity score method is shown to reduce treatment selection bias and has probable merit that need to be further examined. [ABSTRACT FROM AUTHOR]

Tracking vehicles through roundabouts is laborious. Because of this, turning movement volumes are usually estimated using a variety of methods. This paper identifies and evaluates practical methods of estimating turning movement volumes at roundabouts. Thirty four experiments were used to test the effects of different estimation treatments: estimation procedure, time interval size, count location configuration, and turning movement sample procedure. A new economical sampling procedure was introduced and included in the experiment design. The experiments were evaluated using volume estimation and capacity estimation errors. Findings showed that the new sample procedure works well relative to a random sampling procedure. Other insights were gained regarding the four treatments included in the experiment design. [ABSTRACT FROM AUTHOR]

Since the 1980s, the demand for Hong Kong’s container handling facilities has been increasing due to the robust economic growth in South China. As more and more vessels call on Hong Kong’s container terminals, the vessels moving in the basin surrounded by the container terminals will have a bigger chance of interfering with one another, due to the need to comply with navigation safety requirements. The interference often necessitates the vessels to stop occasionally while moving along their navigation paths in order to avoid potential collisions. This paper develops a simulation model for studying the impact of the vessel-traffic interference in Hong Kong’s terminal basin on its container terminals’ capacities. Major navigation safety requirements and terminal operational characteristics are considered in the model. The model’s simulation results show that the delays due to the vessel-traffic interference lead to a considerable reduction in Hong Kong container terminals’ capacities. This model can assist the container terminals in estimating the benefits of coordinating vessel movements in the terminal basin. [ABSTRACT FROM AUTHOR]

This paper describes the design and evaluation of a grid-tied photovoltaic (PV) system to be placed over the existing visitor center skylight for the Independence National Park in Philadelphia, Pa. using an integrated approach. The approach included calibrated building energy and lighting models (sensors and computational), estimation of the PV power produced, and cost taking into consideration the reduction based on cooling energy and emissions avoided by the displacement of purchased electricity (the mix of generating technologies in the local power control area was used to estimate avoided emissions). The design of the PV system was guided by the building orientation and skylight construction and was based on currently available PV modules. Several array sizes were considered since the choice of array size has implications for power production and shading, as well as for building cooling energy demand. [ABSTRACT FROM AUTHOR]

The evaluation of consultant’s performance is crucial to the success of a consulting assignment especially when today’s construction projects are becoming more sophisticated, large-scale, and risky. However, since individual clients have developed their own consultant’s performance evaluation (CPE) procedures, the sharing of performance information, though desirable, may not be too meaningful as the results of evaluation could be inconsistent. There is a need to examine whether a unified framework can be derived for CPE. The aim of this paper is to improve the transparency and rigorousness of CPE through the establishment of an evaluating framework for gauging the performance of engineering consultants. In this paper, a comprehensive set of evaluation criteria is identified, and the significance of these criteria is discussed through an empirical survey. Then, a multicriteria model for evaluating the performance of engineering consultants is presented. The results indicate that once an acceptable CPE framework is devised, the performance scores can be utilized for various purposes, including monitor and control, incentive and sanction, preselection, technical assessment, and bid evaluation. [ABSTRACT FROM AUTHOR]

Crime has been plaguing parking garages in the United States. At The Ohio State University, (OSU) crime on campus, in general, has decreased in recent years; however, crime in OSU parking garages has remained stable in spite of campus-wide efforts to reduce crime. When assessing and evaluating parking garages, occupants employ experience-based judgment that is subjective and imprecise, yet extremely useful. When designers employ the principles of crime prevention through environmental design, they also use subjective variables. An approach that captures the imprecise information in noncrisp expressions reflecting subjective and experience-based variables is the fuzzy logic concept. This concept allows the use of mathematical operations to manipulate and operate on imprecise information or knowledge. Variables such as garage illumination and wall height were collected, fuzzified, and treated as the knowledge base of a model presented in this paper. In addition, numerous experience-based implication rules were developed and employed to evaluate subjective variables. A computer program was developed to illustrate implementation of the model. [ABSTRACT FROM AUTHOR]

Scaling, erosion, and cracking are some manifestations of deterioration of concrete surfaces due to chemical attack, exposure to cyclic freezing and thawing, and so forth. Though a rating of the surface can be done visually using some standard method, such an evaluation still remains largely qualitative and subjective. For laying down specifications and maintenance of structures, quantitative and objective methods are required to assist objective decision-making. This paper reports the results of the application of a modified version of a test procedure that is used to determine the surface texture of pavements using concrete specimens subjected to accelerated deterioration due to cyclic freezing and thawing. It is found that the test can be used in conjunction with others to maintain an objective and quantitative record of deterioration of surface characteristics. The fact that the test is nondestructive, noninvasive, and requires only minimum training of workers and simple tools, makes the proposition of using this test more attractive. A possible classification that can be used for specification writing and maintenance of structures is also suggested. [ABSTRACT FROM AUTHOR]

The new ASCE Vision and Body of Knowledge embraces the attitude toward and skills of lifelong learning, indicating the need of acquiring self-regulated learning (SRL) skills. Although civil engineering education has primarily focused on instilling technological knowledge to students, less attention has been paid toward offering deliberate training for nurturing such required high-order skills based on how people learn. This paper introduces the theoretical construct of SRL and the effective pedagogies of cultivating SRL skills from educational research findings, presents a novel instructional framework and its procedures to support students' SRL skill development, and reports its implementation outcomes in civil engineering curricula at a minority-serving institution. The key instructional strategy is to integrate the prompted self-assessment with the course learning tasks into the students' learning processes. Its effect has been evaluated through the feasible assessment practice. Assessment results reveal that the presented framework may benefit students' learning performance, and the majority of students perceived the importance of SRL skills and were interested in developing SRL skills. The limitations of this study and future improvement are also discussed. [ABSTRACT FROM AUTHOR]