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Design of Close-Fit Liners for the Rehabilitation of Gravity Pipes pp 25-36; https://doi.org/10.1061/9780784415801.ch3

Abstract:
This chapter provides a discussion of methods and inspection tools used in the pipe condition assessments. The goal is to leave the reader with a better understanding of how the data obtained in the field regarding the condition of the existing pipeline and the surrounding soil will be used to design the lining system. The material in this chapter is intended to update and complement material provided in the existing literature on inspection technologies. Closed circuit television (CCTV) has been for many years as the workhorse of gravity pipeline inspection. CCTV equipment is used to provide a visual inspection of the internal surfaces of a pipeline. The Pipeline Assessment Condition Program, or PACP, was originally developed by the National Association of Sewer Service Companies in partnership with the Water Resource Centre (WRc) from the United Kingdom in the early 2000s; the first version was based on WRc's Manual of Sewer Condition Classification.
Design of Close-Fit Liners for the Rehabilitation of Gravity Pipes pp 1-4; https://doi.org/10.1061/9780784415801.ch1

Abstract:
Arriving at an appropriate design for the renewal of an existing buried pipe structure requires a markedly different approach than the design of a new buried pipe installation and is generally more difficult. The design engineer for a new pipe project can further overcome the challenges of the installation site by choosing between a rigid pipe material and a flexible pipe material to address the project site's specific installation and/or safety issues. In a pipe renewal design, the design engineer works with a pipe in given condition, as well as with the given choice of liner material and method of installation. This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book provides guidance to the consulting engineers tasked with designing flexible close-fit liners for the renewal of existing gravity pipe applications in a form that is readily usable.
Design of Close-Fit Liners for the Rehabilitation of Gravity Pipes pp 163-170; https://doi.org/10.1061/9780784415801.bm

Abstract:
Back matter pages come after the papers or chapters in a published work. This back matter contains an appendix, glossary, and index.
Design of Close-Fit Liners for the Rehabilitation of Gravity Pipes; https://doi.org/10.1061/9780784415801.fm

Abstract:
Front matter pages come before the papers or chapters in a published work and include a title page, copyright information, and a table of contents. This publication’s front matter also includes a preface and acknowledgments.
Design of Close-Fit Liners for the Rehabilitation of Gravity Pipes pp 151-152; https://doi.org/10.1061/9780784415801.ch6

Abstract:
This chapter provides conclusions about presented material in the manual and explains why the design approach is very different than has been practiced based on the ASTM F1216. Design methods presented in this manual are applicable to both circular and non-circular liners under certain conditions. The fully analytical model used in this design method is based on the study of the deformation blister that develops in the liner under the effect of external groundwater pressure. Critical shapes (circular, egg shaped) are not easily deformable but are very sensitive to imperfections, in particular the gap which rapidly reduces the critical buckling pressure. Conversely, subcritical shapes are very deformable but are less sensitive to imperfections. The deterioration of the host structure is classified into three levels: State I corresponds to leakage defects, State II concerns fractured rigid structures, and State III concerns highly deformed multi-cracked structures or highly altered flexible structures.
Underground Utilities for Construction Practitioners and Homeowners pp 95-99; https://doi.org/10.1061/9780784415818.bm

Abstract:
This is the index for the publication.
Ahmed Al-Bayati, Louis Panzer
Underground Utilities for Construction Practitioners and Homeowners pp 1-19; https://doi.org/10.1061/9780784415818.ch01

Abstract:
In 1970, the American Public Works Association (APWA) produced a study that highlighted the need to coordinate construction-related activities according to rights of way. This study paved the way for the formation of APWA’s Utility Location and Coordination Council. In the 1950s and 1960s, an earnest effort began to place utilities underground as a way to protect them from climatic damage. This chapter presents key terminologies with which excavators and homeowners should be familiar while addressing damage prevention acts in their states. An evaluation is also included on the benefits of measuring and tracking damage trends to help stakeholders determine appropriate educational focus and identify opportunities for reducing the risk of damage.
Ahmed Al-Bayati, Louis Panzer
Underground Utilities for Construction Practitioners and Homeowners pp 33-51; https://doi.org/10.1061/9780784415818.ch03

Abstract:
This chapter discusses basic duties, as well as desirable and undesirable actions, of designers, professional excavators, and nonprofessionals (homeowners) during planning and design phases. The processes by which contractors, including general contractors and subcontractors, make the majority of the construction phase requests to one-call centers are explored, along with the high proportion of damages to underground utilities resulting from construction activities. Examples are given to illustrate the importance of requesting the most specific information available about the location of the work to be done, as well as the actual type of work and its projected duration. The four nationally recognized steps in the safe excavation process are described: calling before digging, waiting the required time, respecting the marks, and digging with care.
Ahmed Al-Bayati, Louis Panzer
Underground Utilities for Construction Practitioners and Homeowners pp 21-31; https://doi.org/10.1061/9780784415818.ch02

Abstract:
This chapter provides specific details about the one-call process, including how laws govern it, how enforcement and disputes are managed, and the various types of outreach that are performed by one-call centers. The state of North Carolina’s Prevention Act is examined with respect to its emphasis on shared responsibility and the resulting absence of liability on the part of construction establishments to nonresponding or improperly responding operators for damages to operators’ facilities. Focus is also given to the indispensability of fair and balanced enforcement to an effective damage prevention program, as well as the US safety regulation requiring pipeline operators to educate property owners, excavators, and first responders in the communities in which their facilities are located.
Ahmed Al-Bayati, Louis Panzer
Underground Utilities for Construction Practitioners and Homeowners pp 53-65; https://doi.org/10.1061/9780784415818.ch04

Abstract:
This chapter focuses on the role of utilities in the safe digging process. To participate in the one-call system, a utility must have membership in the one-call center(s) where the service territory is located. In an effort to illustrate a typical utility membership, a fictitious company is presented—XYZ Fiber—which provides a footprint of the area where building is planned, the desired method of ticket receipt, and database and damage contact information. Shared responsibility calls for teamwork among stakeholders that creates a smoother work process. SEGRA case study and National Grid case study are provided to show how shared responsibility contributes to lower damages.
Underground Utilities for Construction Practitioners and Homeowners; https://doi.org/10.1061/9780784415818.fm

Abstract:
Front matter pages come before the papers or chapters in a published work and include a title page, copyright information, and a table of contents. This publication’s front matter also includes a preface and other items.
Impacts of Future Weather and Climate Extremes on United States Infrastructure pp 1-18; https://doi.org/10.1061/9780784415863.ch1

Abstract:
The strength of US infrastructure is the foundation of its economic strength and position in the world and depends on various critical systems for its maintenance and longevity. Implementing adaptation options for climate change into civil engineering design is complicated by the traditional approaches premised on empirically derived probabilities of risk to characterize functionality, durability, and safety. This book aims to synthesize the available research on individual sector vulnerabilities to disruptive weather and climate and to consider the possible fragility of these systems, given the anticipated changes in climate and adaptation activities. This chapter provides an overview of these key concepts.
Impacts of Future Weather and Climate Extremes on United States Infrastructure pp 149-156; https://doi.org/10.1061/9780784415863.ch5

Abstract:
Much of the existing infrastructure in the United States was designed for the climatic conditions of the twentieth century, and most current engineering minimum design standards have not been updated to address the impact of recent and future climate change. This chapter focuses on the threats posed by future weather and climate extremes to US infrastructure, and provides an assessment of the infrastructure that will benefit most broadly from preventing a cascade of negative impacts. Methodologies are examined that may be used to prioritize adaptation measures to achieve the greatest benefits when time and financial resources are limited. The following overarching groups are considered with respect to their specific vulnerability issues: energy transmission, storage, and distribution; transportation; drinking water and wastewater; flood protection infrastructure; and navigation/ports and harbors.
Impacts of Future Weather and Climate Extremes on United States Infrastructure pp 159-163; https://doi.org/10.1061/9780784415863.in

Abstract:
This is the index for the publication.
Impacts of Future Weather and Climate Extremes on United States Infrastructure pp 19-58; https://doi.org/10.1061/9780784415863.ch2

Abstract:
This chapter explores some of the challenges associated with attributing specific meteorological and hydrological extreme events to global warming. The direct impact of higher temperatures on such critical infrastructure as increased energy demand for cooling purposes, damage to roads and railways, and degraded water quality is reviewed. Details are provided on some of the effects of such extreme upward movements in temperature on other meteorological and hydrological factors that can in turn have substantial impacts on civil engineering infrastructure. These include precipitation, stream flow and runoff, frequency and intensity of droughts and fires, storm tracks, frequency and intensity of tropical cyclones, sea levels and surface temperatures, storm surge, ocean acidity, sea ice extent, frequency of atmospheric icing events, ocean wave height and duration, snow pack duration and depth, and the frequency and cost of natural disasters. The projected influence of global warming on many of these factors is discussed.
Impacts of Future Weather and Climate Extremes on United States Infrastructure pp 129-148; https://doi.org/10.1061/9780784415863.ch4

Abstract:
Many prioritization schemes are based on analysis of the relative merits and drawbacks of improvements or the tangible impacts of failure. This chapter discusses some of the constraints faced by decision makers, followed by an analysis and examples of the possible ways to frame a prioritization scheme. Decision steps are presented that were developed to assist in creating a sector- or location-specific prioritization framework. These decision steps are informed by the United Nations Environment Programme Multi-Criteria Assessment for climate change prioritization tool, and include: understanding the decision context; identifying options for adaptation; identifying criteria and indicators; scoring, weighting, and interpreting results; and conducting a sensitivity analysis.
Task Committee on Future Weather and Climate Extremes, , , , R. Edward Beighley, William J. Capehart, Noah J. Fehrenbacher, Robert E. Fields, , Laurna Kaatz, et al.
Impacts of Future Weather and Climate Extremes on United States Infrastructure; https://doi.org/10.1061/9780784415863

Impacts of Future Weather and Climate Extremes on United States Infrastructure pp 59-128; https://doi.org/10.1061/9780784415863.ch3

Abstract:
Damages from extreme weather events demonstrate current urban infrastructure vulnerabilities. Major stressors that will have the greatest impact on critical infrastructure include more frequent and intense precipitation events, heat waves, coastal flooding, and wildfires. The US energy and transportation systems are major sectors affected by such stressors. These sectors have therefore been organized into the following groups: energy transmission, storage, and distribution infrastructure; transportation; transit and aviation; drinking water and wastewater; flood protection infrastructure; and navigation/ports and harbors. Each sector is examined with respect to potential impacts of climate change, the status of sector resiliency in terms of current needs and climate change adaptation, potential adaptation response or actions to increase sector resiliency, and dependencies and influences on other sectors that may lead to cascading failure.
Tanita Fossli Brustad, , Børre Bang
Journal of Cold Regions Engineering, Volume 35; https://doi.org/10.1061/(asce)cr.1943-5495.0000250

Abstract:
Road conditions during wintertime in northern Norway frequently cause problems for heavy haulers transporting goods. The trucks often experience difficulties when traveling uphill or downhill because of snowfall and ice formation, which again constitutes a safety risk and a nuisance for other road users. In this paper, we report on a series of field tests in which we investigated the impact of targeted sanding on a heavy hauler with a focus on self-help, pull force, and road friction.
Ming Cao, Huiting Yao, Juyi Xia, Gang Fu, Yan Chen, , Junsheng Li, Yuanyuan Zhang
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000695

Abstract:
Urban parks have an important impact on the health of urban residents. Normally, the first step is to identify whether the accessibility of urban parks is equitable; however, multiple models that were applied in previous studies have shown different accuracies. In this study, the area within the fifth ring road of Beijing municipality is selected as the location to conduct the accessibility-based equity assessment of urban parks. The urban park accessibility (UPA) of each residential community will be calculated using the Gaussian two-step floating catchment area (G2SFCA) method. Then, random forest regression and partial dependence plots will be carried out to analyze the relationship between UPA and socioeconomic indicators. To identify where the UPA is inequitable, spatial distribution characteristics between the UPA and socioeconomic indicators will be analyzed based on the bivariate treatment of local indicators of spatial association (LISA). The results indicate the close relationships between UPA and four indicators (towns or subdistricts location = LT, bachelor’s degree (or above) = BD, mean house price = HP, and population density = PD). Beijing urban park unfairness exists in low BD with low UPA or low HP with low UPA streets in the southwestern and east areas of Beijing. In addition, unfairness exists in high PD with low UPA streets in the north second to third ring road areas. Therefore, these areas should be prioritized for urban park development. The methods used in this study could be extended to study the relationship between various service facilities accessibility and influencing factors, and the results could guide intervention programs to help reduce urban park inequity.
Kaike Li, Xinyi Niu
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000702

Abstract:
This study presents a method for delineating a megacity region with functional linkages in a continuous urbanized area. We examine commuting from cellphone network data and delimitate the Shanghai megacity region from 16 cities in the Yangtze River Delta, China. First, we identify places of residence and work based on certain durations of stay in one location from cellphone network data and obtain commuting data in 1 km2 grids. Second, the core area of the megacity region can be defined as a continuous high-density area by applying incoming employment density as a functional linkage. We use local spatial autocorrelation to define the hotspots of continuous high-density areas and identify a Shanghai-centered continuous high-value area. Third, we choose an algorithm that gradually increases the density threshold based on the results of local spatial autocorrelation to eliminate areas with weak functional connectivity, and delineate the boundary of the core area of the Shanghai megacity region. Results show that the core area exceeds the boundary of Shanghai Municipality and comprises the main urbanized areas of Shanghai and Suzhou. This study provides an effective method for delineating megacity regions by using functional linkages from cellphone network data and for accurately delimitating the boundary of megacity regions.
, Stephen Bruneau, Bruce Colbourne
Journal of Cold Regions Engineering, Volume 35; https://doi.org/10.1061/(asce)cr.1943-5495.0000253

Abstract:
Damage of concrete in a marine environment by ice can result in significant degradation of a structure, leading to increased maintenance costs, decreased structural resistance, and decreased operational lifetime. There are a number of approaches to reduce or impede these impacts, such as the choice of concrete used, selection of the structural shape, and coatings to inhibit abrasion. In order to inform these approaches, it is necessary to understand the underlying mechanisms that lead to abrasion, so that appropriate design considerations may be made. Degradation of concrete through the frictional effects of ice is a key component of mechanical abrasion. Adhesion in turn is one of the key components of static friction. This paper examines the state of knowledge of the adhesive effects of large-scale (bulk) ice on concrete and presents the challenges in comparing results across test programs due to the lack of standard test procedures. Research directions are proposed, both to reduce challenges in cross-comparison of research results and to further advance our understanding of the contact mechanics at play in adhesion of ice to concrete and its effect on damage.
Zhiwei Du, Hongou Zhang, , Lixia Jin
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000697

Abstract:
Since the beginning of the 21st century, the phenomenon of urban shrinkage, accompanied by symptoms of a structural crisis in urban areas, has spread on a global scale. The recent 2008 global economic crisis has been proven to have accelerated urban shrinkage in many previously prosperous cities. The city of Dongguan, which is known as the World’s Factory, suffered a manufacturing downturn and labor outflow induced by the crisis; however, it exhibited high resilience as it displayed a quick recovery in the postcrisis period. The notion of regional resilience and its potential applications can explain why urban and regional economies resist and adjust to internal and external challenges in a long-term development process. Based on the adaptive cycle analytical framework, this study focused on specific policies and plans initiated by the Dongguan municipality when it faced the financial crisis and its implementation effects. It contributes to current knowledge by elaborating on how the local state reacted to and coped with crisis-induced shrinkage and by providing a valuable case for exploring the dynamic evolution of shrinkage and resurgence in the context of globalization. Three main resilient strategies are identified: (1) moving toward a more diversified industrial structure; (2) highlighting endogenous momentums in economic transition; and (3) advancing the equalization of social welfare for local residences. Moreover, it provides implications for the urban planning community on how to respond to uncertainty and vulnerability from the perspective of regional resilience.
Nabeel Ahmed Khan, Bishwajit Bhattacharjee
Journal of Architectural Engineering, Volume 27; https://doi.org/10.1061/(asce)ae.1943-5568.0000474

Abstract:
Thermal, visual, and acoustic comfort are among the major parameters of overall occupant comfort and indoor environmental quality in buildings. Early stage design and selection of building envelope parameters require due consideration to all these three aspects of comfort to enhance envelope performance, productivity, and wellbeing of occupants. Several methodologies have been proposed by researchers for optimization of thermal and visual performance of the envelope, both individually and simultaneously, but the acoustic performance, that is, mainly noise insulation, has remained largely disregarded or left to be dealt with at a later stage. The lack of a proper methodology for simultaneous optimization of thermal and visual performance of building envelope with acoustic performance has led to degradation of the acoustic environment inside green buildings. The present study aims to propose a methodology for simultaneous optimization of the thermal, visual, and acoustic performance of the building envelope to minimize operational energy consumption and enhance thermal, visual, and acoustic comfort for the occupants.
Stefano P. de Oliveira, José Roberto D. Luche, Fernando A. S. Marins, Aneirson F. da Silva, Antônio F. B. Costa
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000709

Abstract:
This work develops a mathematical model for designing bikeway networks that integrate into public bus transport services in urban areas using concepts from network multiobjective optimization and mixed-integer linear programming (MILP). The proposed model maximizes 14 objectives and 14 constraints by referring in a generalized way to lane comfort, safety, path objectivity, network connectivity, intermodality with bus service, and monetary budgets. In the context of a developing country, we believe that this model can address the transit network design problem (TNDP) as an innovative proposal for integration between alternative modes of transport and buses. A case study in Sao Jose dos Campos city, Sao Paulo state, Brazil, is conducted, and exact solutions are obtained with partially connected networks (first approach) and fully connected networks (second approach). A scenario analysis enables verification of the integrated transportation system performance and, for the case study, prioritizes the least expensive bikeway type. Therefore, the results from the proposed model can contribute to urban planning in testing alternative scenarios for bike–bus networks.
Sandeep Gandhi, Geetam Tiwari
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000710

Abstract:
Established theories have identified multiple sociopsychological variables that contribute to improving behavior predictions. Researchers have tested their application in explaining travel behavior. This study uses descriptive analysis of data collected on 27 variables of travel behavior. Of these, 21 were relatively new variables, including 16 sociopsychological and five qualitative instrumental variables. Six currently popular demographic and quantitative instrumental variables were also included. It uses interview-based survey data on work trips by users of two private and two public transport modes in Delhi, India. Responses from a total of 406 participants were used. A total of 13 variables show promise in explaining mode-choice behavior. These include four qualitative instrumental variables: “time,” “cost,” “comfort,” and “safety”; six sociopsychological variables: “habit,” “intention,” “perceived behavior control,” “positive symbolism,” “negative symbolism,” and “awareness norm”; and three sociodemographic variables: “education,” “household income,” and “household vehicle ownership.” This makes a case for urban planners as well as transport planners and researchers to consider nontraditional variables for improving the accuracy of travel mode-choice models.
M. Sime, G. Bailey, E. Y. Hajj, R. Chkaiban
Journal of Transportation Engineering, Part B: Pavements, Volume 147; https://doi.org/10.1061/jpeodx.0000272

Abstract:
Fuel consumption increases with pavement roughness, thereby impacting vehicle operating costs. This paper explores the use of physics-based models to simulate a fleet consisting of 29 different vehicles representing a range of vehicle categories, technologies, and fuel types. Each vehicle model was simulated over a gamut of pavement roughness profiles while traveling at steady-state speeds from 16 to 145 km/h to estimate the impact of roughness on the vehicle fuel consumption. Published fuel consumption measurements on a large sport utility vehicle (SUV) and a dump truck gathered before and after pavement resurfacing (road condition going from fair to good) were used for validation of the prediction of change in fuel consumption due to pavement roughness. The simulation results compared closely (within 2%) with the measured data sets for both vehicles.
Panagiotis Ch. Anastasopoulos, Pablo L. Durango-Cohen, Samuel Labi
Journal of Infrastructure Systems, Volume 27; https://doi.org/10.1061/(asce)is.1943-555x.0000621

Ralph Tayeh,
Journal of Architectural Engineering, Volume 27; https://doi.org/10.1061/(asce)ae.1943-5568.0000476

Abstract:
The technological advancements of the twenty-first century have great potential for improving the construction industry’s low levels of productivity. Many companies are adopting new technologies to help them in their everyday work and automate some of their tasks. With the increased demand for skilled workers who are able to adapt to the new technological changes, it is essential for schools to provide their students with the necessary skills to enter the market and be successful professionals. This research presented the results of a Delphi study conducted to assess the level of knowledge in technological topics expected from graduates when joining the industry. The expectations were measured from the industry side and the academic side and compared based on the job position. Based on the collected results, two graduate construction technology courses were designed and described in this paper. These courses covered topics related to information modeling, reality capture, visualization techniques, generative design, robotics, and automation. The paper also assessed the use of virtual reality and collaborative online platforms for building information models for class group projects. It also discussed the benefits of using these technologies from the viewpoint of students and instructors.
Yanqiang Yang, Baohua Mao, Min Wang
ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering, Volume 7; https://doi.org/10.1061/ajrua6.0001140

Abstract:
Steep ramps are often unavoidable in route design, leading to adverse effects on freight transportation organization. For operators, how to safely and effectively run trains on steep downhill lines is a challenging task. In response to the requirement, firstly, the control principles of electric freight trains, including safety demands, rapid running, use of driving modes, and periodic braking, are analyzed. Then, a fast train operation simulation algorithm (FTOSA) is proposed to realize the control principles. Finally, a real case study is carried out, and FTOSA is compared with existing simulation software in China. The results showed that FTOSA could generate a high-efficiency speed profile on long steep downhill lines under the constraints of train safety control. This work can provide some references for the operation of electric freight trains.
Christopher A. T. Castillo, Adam J. Hand, Peter E. Sebaaly, Elie Y. Hajj,
Journal of Transportation Engineering, Part B: Pavements, Volume 147; https://doi.org/10.1061/jpeodx.0000277

Abstract:
Cracking is an expensive asphalt concrete (AC) pavement distress to repair. Fatigue and reflective cracking are the two primary types of cracking that impact AC pavement service life. Fatigue cracks initiate at the bottom of an AC layer due to repetitive bending under traffic loads, whereas cracks in the existing AC pavement tend to reflect through the AC overlay quickly. The objective of this study was to evaluate the impact of rubber-modified binders on the fatigue and reflective cracking resistances of AC mixtures. This research evaluated the resistance of unmodified, polymer and tire rubber–modified, and tire rubber–modified AC mixtures to fatigue and reflective cracking. The AC mixtures were designed following the Superpave volumetric mix design method, and dynamic modulus master curves were developed for each mixture. The performance characteristics of the mixtures were evaluated in terms of their resistance to moisture damage, rutting, fatigue cracking, and reflective cracking. Mechanistic analysis of a typical AC pavement was then conducted to assess the impact of the three mixtures on pavement performance life. The mechanistic analysis indicated that the combination of tire rubber and polymer modification offers slightly better resistance to fatigue cracking than tire rubber alone. Both tire rubber mixtures showed superior fatigue performance compared to the unmodified mixture. In the case of reflective cracking, the tire rubber–modified mixtures showed superior resistance to reflective cracking compared to the unmodified and polymer and tire rubber–modified mixtures while maintaining similar resistance to moisture damage and adequate resistance to rutting.
Anil Kumar Agrawal, Glenn Washer, Sreenivas Alampalli, Xu Gong, Ran Cao
Journal of Infrastructure Systems, Volume 27; https://doi.org/10.1061/(asce)is.1943-555x.0000622

Abstract:
Previous studies by the Federal Highway Administration (FHWA) have shown significant variability in the rating of bridge elements through visual inspection. In this study, a detailed evaluation of the consistency of inspection ratings of four representative bridges in New York State has been conducted, using inspection data reported by 21 inspection teams employed by the New York State Department of Transportation (NYSDOT). The bridge condition rating scale of NYSDOT ranges from 7 to 1, with 7 being new and 1 being in a failed condition. In addition, the NYSDOT assigns ratings 8 and 9 to cases “not applicable” and “condition and/or existence unknown,” respectively. In general, consistency is defined as “conformity with practices and procedures.” In this study, consistency of inspection of elements has been quantified as a percentage of inspectors that rated the bridge element within ±1 of the median rating for elements with ratings 7 to 1, or as a percentage of inspectors who have assigned a rating of 8 or 9 to elements expected to be rated 8 or 9. Based on the evaluation of the consistency of elements of the four bridges in the study, the results show that 96% of the elements have a consistency of at least 90%. Only seven elements have been identified to have a consistency of less than 90%. For elements whose rating was supposed to be 8, approximately 97% of the elements had a consistency of at least 90%, whereas, for elements whose rating was supposed to be 9, 91% of the elements were inspected with a consistency of at least 95%. Overall team consistency based on inspection of all elements was approximately 98%. The results imply that the NYSDOT bridge inspection and training programs are effective, as evidenced by the reporting of consistent bridge ratings by multiple inspection teams.
Zhen Liu, Xingyu Gu, Qiao Dong, Shanshan Tu, Shuwei Li
Journal of Transportation Engineering, Part B: Pavements, Volume 147; https://doi.org/10.1061/jpeodx.0000280

Abstract:
Building information modeling (BIM) is well-known for improving the efficiency of the Architecture, Engineering, and Construction (AEC) industries. Currently, the support for web displays using web graphics library (WebGL) technology in BIM has gained popularity. To address issues of insufficient display for airport pavements by two-dimensional (2D) methods and the huge amount of data storage requirements for large-scale BIM scenes, this paper presents a visualization method for differential expressions for airport pavement quality on web-based three-dimensional (3D) models combined with Revit and Three.js software. An airport is used as an example to discuss the effects of quality displays by integrating BIM and WebGL. The results indicate that Revit software has good adaptability in establishing an airport pavement model, and the BIM browser can display the quality of the airport pavement intuitively, displaying such parameters as pavement condition index (PCI), cracking, and patching. These findings provide compelling evidence for 3D displaying and rendering of quality conditions for transportation infrastructure. Moreover, this research suggests that this approach is effective in improving the information and intelligence levels of the Airport Pavement Management System (APMS).
Abril Yu-Shan,
Journal of Transportation Engineering, Part B: Pavements, Volume 147; https://doi.org/10.1061/jpeodx.0000276

Abstract:
Excess moisture and pore pressure in pavements are significant causes of road deterioration. The evaluation of pavement degradation in flood events and water table rises is critical to proposing better designs and mitigation plans. Consequently, a three-dimensional finite-element simulation based on Biot consolidation theory and asphalt viscoelasticity under a moving tire load was developed to accurately analyze the detrimental effects of saturated layers in asphalt pavements. A parametric study was conducted to investigate pavements’ structural responses of varying asphalt concrete and base thickness, base and subgrade permeability, and vehicle speeds under different levels of saturation. The results demonstrated how saturation scenarios can increase the longitudinal strain at the bottom of asphalt concrete and therefore cause rutting. The asphalt concrete and base thickness, vehicle speed, and base and subgrade permeability are shown to highly affect the distribution of pore pressure–inducing stripping in the asphalt layer. Therefore, the outcome emphasizes the importance of considering the effects of increasing flood events in pavement designs and maintenance plans.
, Mohammad Rahi, , Eshagh Babaii Ashourabadi, Sahar Maniei, Pedram MohammadGhasemi, Ellie H. Fini
Journal of Transportation Engineering, Part B: Pavements, Volume 147; https://doi.org/10.1061/jpeodx.0000275

Abstract:
This paper examined the merits of using a polymer nanocomposite containing styrene-ethylene/propylene-styrene (SEPS) and montmorillonite (MMT) clay to enhance bitumen thermomechanical properties. To investigate the effects of hybrid usage of SEPS and MMT on bitumen properties, a series of physiochemical and rheological characterization was performed, including frequency sweep tests, multiple stress creep and recovery (MSCR) tests, bending beam rheometer (BBR) tests, and linear amplitude sweep (LAS) tests. Three different dosages (2%, 4%, and 6%) of SEPS and 5% nanoclay were used to modify the original bitumen. The study results showed that the addition of SEPS increased the high-temperature performance of bitumen based on the increase of complex modulus and recoverable strain (R). As the percentage of SEPS increased from 2% to 6%, the high-temperature grade of bitumen increased from 64°C to 82°C, and the low-temperature grade decreased from −22°C to −16°C. Nanoclay had an additional stiffening effect while enhancing the storage stability of bitumen. The hybrid use of SEPS and MMT also improved the aging resistance of bitumen as evidenced by a lesser increase in carbonyl functional groups when exposed to oxidation, as measured by Fourier transform infrared spectroscopy (FTIR). The latter improvement was attributed to SEPS and MMT’s compatibility, leading to polymer intercalation into clay intercalary spacing, promoting clay exfoliation. Exfoliated silica platelets of clay can act as a barrier to oxygen diffusion into the bitumen matrix, delaying oxidation.
, Alireza Naderi
Journal of Aerospace Engineering, Volume 34; https://doi.org/10.1061/(asce)as.1943-5525.0001279

Abstract:
In this work, an implicit finite-volume-element (FVE) method is extended to efficiently simulate the vortical structure of unsteady turbulent flows in domains with moving meshes. The arbitrary Lagrangian-Eulerian (ALE) approach is used to consider the motion of a hybrid mesh distributed in the solution domain. Conventional turbulence models are applied to simply confirm the sample achieved efficiency and accuracy in solving complex turbulent flow domains with moving boundaries. In this regard, the advective terms in the Navier-Stokes equations, including those in the transport equations for the applied turbulence models, are treated in a rather innovative manner. In other words, an advanced physical influence scheme (PIS) is suitably introduced in the context of extended ALE formulations. The accuracy and efficiency of the extended method are carefully evaluated by simulating various turbulent flows, including the fluid flow in stationary domains, separated turbulent flow over a bluff body problem, and the dynamic stall of fluid flow over a flapping airfoil. Comparing the current solutions with experimental data, it is shown that the current PIS-ALE method provides better accuracy and efficiency than those of past numerical methods, which used similar turbulence models in their algorithms.
Sparsh Johari, Kumar Neeraj Jha
Journal of Management in Engineering, Volume 37; https://doi.org/10.1061/(asce)me.1943-5479.0000941

Abstract:
Workplace training aims to enhance the performance of trainees by improving their specific skills. Unfortunately, the outcome of such trainings in terms of the percentage of increase in trainees’ performance is not generally measured. On one hand, this lack of measurement results in contractors not recognizing the importance of training in enhancing workers’ performance, and on the other hand, the training providers do not receive constructive feedback on the efficacy of their sessions. This study therefore attempts to bridge this gap by developing a regression model of the socioemotional, cognitive, and technical skills of workers and their performance. Data was collected on 137 workers from four training centers in India. Using the developed model, a learning curve was drawn between performance and training time. Additionally, skills versus training time curves were also plotted. The results indicate that workers’ performance after training was far below the desired level of employers; the reason for this emerges from skills versus training time curves, where it is found that the training does not focus on enhancing socioemotional and cognitive skills. Therefore, the study recommends that training providers incorporate these skills in their training curriculum to achieve more desirable outputs from training.
Mei Liu, , Pin-Chao Liao, Tsenguun Ganbat
Journal of Infrastructure Systems, Volume 27; https://doi.org/10.1061/(asce)is.1943-555x.0000617

Abstract:
International construction is a high-risk undertaking with multiple objectives and uncertainties. This study aims to clarify the complex relationships between the risks of international construction and the objectives of sustainable project performance. The scope of sustainable project performance includes the environment and health and safety in addition to the common project objectives of cost, time, and quality. A metanetwork modeling approach was adopted to analyze and evaluate the impact of each risk and its relationship with the project objectives, which were built using a case study and questionnaire data. The results indicate that despite the common impact of the increased material prices on the cost objective, the risk of environmental problems caused by contractors during the construction stage had the greatest impact on international construction. At the construction site, decision-makers or managers can clearly identify risk relationships and control the corresponding risks to the project objectives. This study identifies the relationships between the risks and the project objectives and can serve as a practical reference for managing international construction.
Can Cui, Chengchao Guo, , Fuming Wang, Hongyuan Fang
Journal of Transportation Engineering, Part B: Pavements, Volume 147; https://doi.org/10.1061/jpeodx.0000285

Abstract:
Polyurethane grouting technology has been applied in the maintenance and reinforcement of transportation infrastructure such as airports, expressways, and high-speed railways. For rigid pavements with voids underneath concrete slabs, it can make a quick and efficient fix. However, polyurethane grouting materials applied underneath slabs for base enhancement are subjected to cyclic compressive loading from traffic, so their fatigue performance is critical in the concrete–polyurethane composite structure. There have not been many studies of this aspect. This paper investigated the influence of several key design factors, including grout thickness, grout density, and void shape, on the stress–strain and fatigue performance of the concrete–polyurethane composite structure. Laboratory compressive tests were conducted at various stress levels following a four-factor, three-level orthogonal experiment design. The results showed that the strain response of composite specimens under stress-controlled cyclic loading may be divided into three stages: an initial stage in which the cumulative strain changes little with the number of load repetitions, a second stage in which the cumulative strain increases steadily with the number of load repetitions, and a third stage in which the cumulative strain increases rapidly with the number of load repetitions. The third stage represents the occurrence of fatigue failure. The rank of the influences of the four factors on fatigue performance is, from high to low, grout thickness, stress ratio, void shape, and grout density.
, Shamim N. Pakzad
ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering, Volume 7; https://doi.org/10.1061/ajrua6.0001142

Abstract:
This study presents frameworks to build nonintrusive polynomial chaos expansion (PCE) models with regression and Smolyak sparse-grid quadrature to perform high-dimensional uncertainty propagation and uncertainty quantification (UQ) for response estimated with the hybrid data + model-based submodeling (HDMS) method. The HDMS method drives the finite-element submodel containing a critical location of a structure using the measured response of the real structure at the preselected submodel boundaries to estimate a refined response distribution around the critical location. The proposed UQ frameworks are implemented on an experimental case study of a plate with holes as critical locations under tensile loading. The UQ results at the critical locations from regression-based PCE models built using different sampling methods and the Smolyak sparse-grid quadrature-based PCE models are compared with the UQ results from the traditional Monte Carlo simulation (MCS) method. The regression-based PCE model with Smolyak sparse-grid sampling demonstrated significantly higher accuracy in distribution parameters and probability density functions (pdf) compared to the other regression-based PCE models. While the Smolyak quadrature-based PCE model with a considerably small experimental design showed slightly lower accuracy, it still outperforms regression-based PCE models with MC-based sampling.
Kyung-Tae Lee, Ju-Mi Lee, Ju-Hyung Kim
Journal of Management in Engineering, Volume 37; https://doi.org/10.1061/(asce)me.1943-5479.0000945

Abstract:
In sustainable international development projects, a negotiation guideline for donor and recipient countries is essential to reduce conflicts among various stakeholders in project-based organizations (PBOs) consisting of leadership, senior executioner board, change management board, and executioner. This paper presents a guide focusing on the roles and responsibilities (R&R) of stakeholders according to the hierarchy in PBOs. R&R are classified to keep sustainability at multiple levels while balancing three controversial values: economic growth, social equity, and environmental protection. The proposed guideline was constructed from a literature review as a theoretical framework of R&R and relevant sustainability factors. Moreover, the guide was validated by conducting semistructured interviews and surveys with high-level decision makers. The results show that focused values and potential risks can be identified according to individual R&R in PBOs. Furthermore, sharing responsibilities among levels is necessary. This includes balancing sustainability values between the environmental and non-environmental aspects at the upper level and deploying full-time on-site managers to avoid conflicts with locals at the execution level.
Appupillai Baskaran, Mauricio Chavez, Sudhakar Molleti
Journal of Architectural Engineering, Volume 27; https://doi.org/10.1061/(asce)ae.1943-5568.0000475

Abstract:
The North American Vegetated Roof Assembly (VRA—a.k.a. green roofs) market is dominated by two different types: modular vegetated roof assemblies (MVRAs) and built-in-place vegetated roof assemblies (BVRAs). In MVRA, the vegetation is pregrown in transportable trays and installed on the roof, whereas in the BVRA, the vegetation develops on the roof. In 2015, the National Research Council of Canada (NRC), in collaboration with the green roof industry and roofing industry, set the national standard for the wind resistance evaluation of MVRA. Practitioners and building authorities have widely used this standard. In 2017, NRC and the industry collaborators started a new research project on BVRA to expand the current standards. The wind performance of BVRA is highly dependent on the growth stage of the vegetation. This variable was investigated by testing four BVRA sources (S1, S2, S3, and S4) at three different growth stages, namely, as-built, 12 weeks, and 1 year of growth. The interaction between the approaching wind speed and the BVRA response was monitored by installing load cells underneath the test mock-up. The load cells were intended to capture the growth media loss as the wind flow develops over the BVRA mock-up. The wind speed at which the vegetated system’s (VS) weight reaches 85% of the initial weight was used to compute the BVRA wind performance. The tests conducted at the three growth stages permitted developing an empirical growth modifier factor (GMF). The GMF is a practical engineering solution to estimate the wind performance of a 1-year BVRA using the as-built performance data. The paper presents the development of this new testing methodology and the standardization process.
Nana Cui,
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000716

Abstract:
The commonly used traditional hedonic price model is likely to be biased in exploring residents' willingness to pay for school quality because of unobservable characteristics. To circumvent this issue, using city-level and district-level key primary school attendance zones data and average home value data of communities in Beijing in December 2016, we employ paired difference regression using a boundary fixed effect approach to explore the capitalization of school quality, with 750 m as the threshold distance within community pairs and 500 and 1,000 m for robustness checks. The results indicate that housing prices respond significantly to both city-level and district-level school qualities in Beijing, with premiums of 17.2% and 8.37%, respectively. However, we find no premium for housing rent. Homeowners show concern over good school quality and are willing to pay more for higher school quality, while renters will not pay for it. This study further suggests that the traditional hedonic price model has overestimated the capitalization of school quality in housing. The estimation results from the boundary fixed effect approach are more robust and reliable. Based on these findings, urban policy recommendations and action plans are proposed.
ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering, Volume 7; https://doi.org/10.1061/ajrua6.0001147

Abstract:
Reliability-based design optimization (RBDO) is a well-known design strategy in engineering. However, RBDO usually requires uncertainties to be modeled by statistical distributions. This requires the availability of sufficient sample size so that these variables can be represented accurately by probabilistic distributions. In the design of new systems and structures, usually there is a lack of information about some uncertain variables or parameters and only a reduced set of samples might be available. This prevents their treatment as probability distributions. This type of uncertainty is called epistemic uncertainty. This paper proposes two effective multiobjective evolutionary algorithms to solve design problems under both types of uncertainty: aleatory and epistemic. Two objective functions, namely the cost of the structures and the probability of failure, are considered. The results are Pareto fronts with a trade-off between cost and reliability associated with a specified level of confidence. Pareto fronts show minimum achievable values for the probability of failure for a given cost. The effect of the epistemic uncertainty on the solution is also investigated. An analytical example and two structural examples are solved to show the applicability of the approach and how epistemic uncertainty may affect the results.
Wenheng Wu, Zhuhui Ding, Kun Huang, Yan Song, Haixia Dong
Journal of Urban Planning and Development, Volume 147; https://doi.org/10.1061/(asce)up.1943-5444.0000707

Abstract:
China’s residential social space has changed significantly following economic reform in 1978. Enterprise communities (ECs) are walled-off residential spaces that were built and managed mostly by the state or collectively owned enterprises to house workers during the 1950s to 1970s. Many ECs are still used in urban China, but they are primary sites for urban poverty. This paper used point of interest (POI) data, field surveys, and spatial analysis to analyze the distribution of ECs in Xi’an, China, and assess the policy implications. Results indicated that the ECs were mainly located in the inner city and were characterized by small-scale agglomeration or cluster distribution along the former major transport routes. The ECs are sites of urban poverty because of industrial transition. Their large renewal potential as construction land should be fully recognized. This study will help to better understand and optimize urban internal space and may apply to countries or regions with similar housing types and urban space. Exploring the relevant issues of postsocialist ECs through POI data can enrich and strengthen scientific research in urban residential areas.
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