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- Genre: Doctoral Dissertation
Description
Civil infrastructures are susceptible to damage under the events of natural or manmade disasters. Over the last two decades, the use of emerging engineering materials, such as the fiber-reinforced plastics (FRPs), in structural retrofitting have gained significant popularity. However, due to their inherent brittleness and lack of energy dissipation, undesirable failure modes of the FRP-retrofitted systems, such as sudden laminate fracture and debonding, have been frequently observed. In this light, a Carbon-fiber reinforced Hybrid-polymeric Matrix Composite (or CHMC) was developed to provide a superior, yet affordable, solution for infrastructure damage mitigation and protection. The microstructural and micromechanical characteristics of the CHMC was investigated using scanning electron microscopy (SEM) and nanoindentation technique. The mechanical performance, such as damping, was identified using free and forced vibration tests. A simplified analytical model based on micromechanics was developed to predict the laminate stiffness using the modulus profile tested by the nanoindentation. The prediction results were verified by the flexural modulus calculated from the vibration tests. The feasibility of using CHMC to retrofit damaged structural systems was investigated via a series of structural component level tests. The effectiveness of using CHMC versus conventional carbon-fiber reinforced epoxy (CF/ epoxy) to retrofit notch damaged steel beams were tested. The comparison of the test results indicated the superior deformation capacity of the CHMC retrofitted beams. The full field strain distributions near the critical notch tip region were experimentally determined by the digital imaging correlation (DIC), and the results matched well with the finite element analysis (FEA) results. In the second series of tests, the application of CHMC was expanded to retrofit the full-scale fatigue-damaged concrete-encased steel (or SRC) girders. Similar to the notched steel beam tests, the CHMC retrofitted SRC girders exhibited substantially better post-peak load ductility than that of CF/ epoxy retrofitted girder. Lastly, a quasi-static push over test on the CHMC retrofitted reinforced concrete shear wall further highlighted the CHMC's capability of enhancing the deformation and energy dissipating potential of the damaged civil infrastructure systems. Analytical and numerical models were developed to assist the retrofitting design using the newly developed CHMC material.
ContributorsZhou, Hongyu (Author) / Attard, Thomas L (Thesis advisor) / Fafitis, Apostolos (Thesis advisor) / Mignolet, Marc P (Committee member) / Ariaratnam, Samuel (Committee member) / Thomas, Benjamin (Committee member) / Blumsom, Jim (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation presents a portable methodology for holistic planning and optimization of right of way infrastructure rehabilitation that was designed to generate monetary savings when compared to planning that only considers single infrastructure components. Holistic right of way infrastructure planning requires simultaneous consideration of the three right of way infrastructure components that are typically owned and operated under the same municipal umbrella: roads, sewer, and water. The traditional paradigm for the planning of right way asset management involves operating in silos where there is little collaboration amongst different utility departments in the planning of maintenance, rehabilitation, and renewal projects. By collaborating across utilities during the planning phase, savings can be achieved when collocated rehabilitation projects from different right of way infrastructure components are synchronized to occur at the same time. These savings are in the form of shared overhead and mobilization costs, and roadway projects providing open space for subsurface utilities. Individual component models and a holistic model that utilize evolutionary algorithms to optimize five year maintenance, rehabilitation, and renewal plans for the road, sewer, and water components were created and compared. The models were designed to be portable so that they could be used with any infrastructure condition rating, deterioration modeling, and criticality assessment systems that might already be in place with a municipality. The models attempt to minimize the overall component score, which is a function of the criticality and condition of the segments within each network, by prescribing asset management activities to different segments within a component network while subject to a constraining budget. The individual models were designed to represent the traditional decision making paradigm and were compared to the holistic model. In testing at three different budget levels, the holistic model outperformed the individual models in the ability to generate five year plans that optimized prescribed maintenance, rehabilitation and renewal for various segments in order to achieve the goal of improving the component score. The methodology also achieved the goal of being portable, in that it is compatible with any condition rating, deterioration, and criticality system.
ContributorsCarey, Brad David (Author) / Lueke, Jason S (Thesis advisor) / Ariaratnam, Samuel (Committee member) / Bashford, Howard (Committee member) / Arizona State University (Publisher)
Created2012
Description
The thesis examines how high density polyethylene (HDPE) pipe installed by horizontal directional drilling (HDD) and traditional open trench (OT) construction techniques behave differently in saturated soil conditions typical of river crossings. Design fundamentals for depth of cover are analogous between HDD and OT; however, how the product pipe is situated in the soil medium is vastly different. This distinction in pipe bedding can produce significant differences in the post installation phase. The research was inspired by several incidents involving plastic pipe installed beneath rivers by HDD where the pipeline penetrated the overburden soil and floated to the surface after installation. It was hypothesized that pipes installed by HDD have a larger effective volume due to the presence of low permeability bentonite based drilling fluids in the annular space on completion of the installation. This increased effective volume of the pipe increases the buoyant force of the pipe compared to the same product diameter installed by OT methods, especially in situations where the pipe is installed below the ground water table. To simulate these conditions, a real-scale experiment was constructed to model the behavior of buried pipelines submerged in saturated silty soils. A full factorial design was developed to analyze scenarios with pipe diameters of 50, 75, and 100 mm installed at varying depths in a silty soil simulating an alluvial deposition. Contrary to the experimental hypothesis, pipes installed by OT required a greater depth of cover to prevent pipe floatation than similarly sized pipe installed by HDD. The results suggested that pipes installed by HDD are better suited to survive changing depths of cover. In addition, finite element method (FEM) modeling was conducted to understand soil stress patterns in the soil overburden post-installation. Maximum soil stresses occurring in the soil overburden between post-OT and HDD installation scenarios were compared to understand the pattern of total soil stress incurred by the two construction methods. The results of the analysis showed that OT installation methods triggered a greater total soil stress than HDD installation methods. The annular space in HDD resulted in less soil stress occurring in the soil overburden. Furthermore, the diameter of the HDD annular space influenced the soil stress that occurred in the soil overburden, while the density of drilling fluids did not vastly affect soil stress variations. Thus, the diameter of the annular space could impact soil stress patterns in HDD installations post-construction. With these findings engineers and designers may plan, design, and construct more efficient river-crossing projects.
ContributorsCho, Chin-sŏng (Author) / Ariaratnam, Samuel (Thesis advisor) / Lueke, Jason (Thesis advisor) / Arizona State University (Publisher)
Created2012
Description
Large-scale civil infrastructure systems are critical for the functioning and development of any society. However, these systems are often vulnerable to degradation and the effects of aging, necessitating consistent monitoring and maintenance. Current methods for infrastructure maintenance primarily rely on human intervention and need the implementation of advanced sensing and computing technologies in field operations and maintenance (O&M) tasks. This research aimed to address these gaps and provide novel contributions. Specifically, the objectives of this study were to leverage artificial intelligence models to enhance point cloud noise processing, to automate tree species detection using Mask R-CNN, and to integrate imagery data and LiDAR datasets for real-time terrain analysis. First, the study proposed leverages neural networks to eliminate unwanted noise from point cloud datasets, enhancing the accuracy and reliability of infrastructure data. Secondly, the research integrated Mask R-CNN into automated tree species detection. This component offers an efficient solution to identify and classify vegetation surrounding infrastructure, enabling infrastructure managers to devise proactive vegetation management strategies, thereby reducing risks associated with tree-related incidents. Lastly, the study fused image and LiDAR datasets to support real-time terrain analysis. This integrated approach provides a comprehensive understanding of terrain characteristics, allowing infrastructure managers to assess slope, elevation, and other relevant factors, facilitating proactive maintenance interventions and mitigating risks associated with erosion. These contributions collectively underscore the potential of artificial intelligence models in advancing the operations and maintenance practices of large civil infrastructure systems. By leveraging these models, infrastructure managers can optimize decision-making processes, streamline maintenance efforts, and enhance critical infrastructure networks' overall resilience and sustainability.
ContributorsPaladugu, Bala Sai Krishna (Author) / Grau, David (Thesis advisor) / Ernzen, James (Committee member) / Standage, Richard (Committee member) / Arizona State University (Publisher)
Created2023
Description
The consequences of failures from large-diameter water pipelines can be severe. Results can include significant property damage, damage to adjacent infrastructure such as roads and bridges resulting in transportation delays or shutdowns, adjacent structural damage to buildings resulting in loss of business, service disruption to a significant number of customers, loss of water, costly emergency repairs, and even loss of life. The American Water Works Association’s (AWWA) 2020 “State of the Water Industry” report states the top issue facing the water industry since 2016 is aging infrastructure, with the second being financing for improvements. The industry must find innovative ways to extend asset life and reduce maintenance expenditures. While are many different assets comprise the drinking water industry, pipelines are a major component and often neglected because they are typically buried. Reliability Centered Maintenance (RCM) is a process used to determine the most effective maintenance strategy for an asset, with the ultimate goal being to establish the required function of the asset with the required reliability at the lowest operations and maintenance costs. The RCM philosophy considers Preventive Maintenance, Predictive Maintenance, Condition Based Monitoring, Reactive Maintenance, and Proactive Maintenance techniques in an integrated manner to increase the probability an asset will perform its designed function throughout its design life with minimal maintenance. In addition to determining maintenance tasks, the timely performance of those tasks is crucial. If performed too late an asset may fail; if performed too early, resources that may be used better elsewhere are expended. Utility agencies can save time and money by using RCM analysis for their drinking water infrastructure. This dissertation reviews industries using RCM, discusses the benefits of an RCM analysis, and goes through a case study of an RCM at a large aqueduct in the United States. The dissertation further discusses the consequence of failure of large diameter water pipelines and proposes a regression model to help agencies determine the optimum time to perform maintenance tasks on large diameter prestressed concrete pipelines using RCM analysis.
ContributorsGeisbush, James R (Author) / Ariaratnam, Samuel T (Thesis advisor) / Grau, David (Committee member) / Chong, Oswald (Committee member) / Arizona State University (Publisher)
Created2024
Description
The accelerated pace of globalization necessitates that civil engineering graduates possess a broad spectrum of competencies to meet the evolving needs of a dynamic, interconnected professional environment. This necessity encompasses a blend of practical, personal, and intercultural skills in aspiring engineers, driven by employers' increasing demand for multifaceted skill sets. International research experiences are pivotal in bridging the gap between traditional academic training and the complexities of the real world, offering substantial benefits in terms of personal growth, intercultural understanding, and enhanced research innovation through exposure to diverse methodologies and global professional networks. Despite these advantages and the critical need for engineers adept at navigating the global landscape, participation in international programs remains markedly low among civil engineering graduates, underlining an urgent need for increased engagement and methodological research to elucidate the immediate and long-term benefits of such experiences. This dissertation critically assesses the effects of international research experience on developing key competencies of graduate students, including personal, academic, and professional development, intellectual growth, and intercultural competence. Recognizing the scarcity of rigorous, empirical studies capturing the comprehensive benefits of abroad research, this study adopts a mixed-methods approach, combining quantitative surveys with qualitative interviews to enhance the validity and reliability of findings through data triangulation. Additionally, data collection occurs at multiple time points before and after the experience, providing an in-depth exploration of how such experiences contribute not only to immediate skill enhancement but also to sustained competence development. The research addresses a critical gap in the existing literature, providing evidence-based insights into the multifaceted value and transformative potential of these experiences on graduate engineering competence advancement. The findings indicate improvements in academic proficiency, marked by adopting innovative research techniques and professional capabilities through expanded networks and enhanced communication skills. Moreover, immersion in international settings elevated students' self-reliance and global consciousness, alongside fostering comprehensive growth in intercultural understanding, thereby contributing to their holistic development across personal, intellectual, and professional domains. Through this comprehensive analysis, the study aims to offer actionable recommendations for designing and evaluating future research programs abroad to foster engineering graduates with the advanced competencies required to tackle contemporary challenges and flourish in the global environment.
ContributorsMehrabi Moezabadi, Daniel (Author) / Grau, David (Thesis advisor) / Ariaratnam, Samuel (Thesis advisor) / Edward Gibson, George (Committee member) / Arizona State University (Publisher)
Created2024
Description
Innovative project delivery methods and project management systems have advanced the world of construction engineering and management, yet the benefits of their applications remain not wholly accomplished without accompanying them with the suitable methods of implementation. As integrated delivery methods have arisen from the need for faster project delivery with early teams’ involvement, their benefits are not attained unless they are executed by the most qualified contracting firms for the job and administered following collaborative approaches. More holistically, integrated project management systems support meeting project guidelines while enforcing the social role played by individuals and teams in addressing challenges that influence their technical performance. Thus, the author was one of the 41 team members that developed an innovative IPM framework which is the Integrated Project/Program Management Maturity and Environment Total risk Rating known as IP2M METRR that helps them review their project team environment and levels of system maturity. Like the integrated delivery methods, an IPM framework is not expected to solve challenges on its own unless supported with guidance for practitioners to efficiently implement the framework. Thus, in this dissertation the author aims to address the challenges by studying the implementation of innovative methods for integrated delivery and integrated management in large government-owned engineering construction projects. The objective is to guide the implementation of (1) design-build (D-B) and construction manager-general contractor (CM-GC) methods in the contractor procurement phase and post-award contract administration phase; and (2) earned value management system (integrated project management application) through a paradigm shift in its assessment, using the IP2M METRR, and focusing on the novel sociotechnical aspect. The author studied data from 128 government-owned projects with total worth of about $46.7 U.S. billion, 11 experts, and 215 practitioners; and used mixed-methods research and industry engaging research techniques, including remote research charrettes which the author supported its development and testing and reported on in this dissertation.The contributions of this dissertation include: (1) identifying best practices for D-B and CM-GC contractor procurement, (2) developing D-B and CM-GC contract administration tool selection framework, (3) gauging lessons learned on IP2M METRR application, (4) identifying issues and recommendations in IPM application implementation, (5) validating IP2M METRR framework, and (6) developing and testing industry-engaging research approach.
ContributorsSanboskani, Hala (Author) / El Asmar, Mounir (Thesis advisor) / Grau, David (Thesis advisor) / Gibson, Jr., George E. (Committee member) / Bearup, Wylie (Committee member) / Kaloush, Kamil (Committee member) / Arizona State University (Publisher)
Created2024
Description
Much of the water and wastewater lines in the United States are nearing the end of their useful life. A significant reinvestment is needed in the upcoming decades to replace or rehabilitate the water and wastewater infrastructure. Currently, the traditional method for delivering water and wastewater pipeline engineering and construction projects is design-bid-build (DBB). The traditional DBB delivery system is a sequential low-integration process and can lead to inefficiencies and adverse relationships between stakeholders. Alternative project delivery methods (APDM) such as Construction Manager at Risk (CMAR) have been introduced to increase stakeholder integration and ultimately enhance project performance. CMAR project performance impacts have been studied in the horizontal and vertical construction industries. However, the performance of CMAR projects in the pipeline engineering and construction industry has not been quantitatively studied.
The dissertation fills this gap in knowledge by performing the first quantitative analysis of CMAR performance on pipeline engineering and construction projects. This study’s two research objectives are:
(1) Develop a CMAR baseline of commonly measured project performance metrics
(2) Statistically compare the cost and schedule performance of CMAR to that of the traditional DBB delivery method
A thorough literature review led to the development of a data collection survey used in conjunction with structured interviews to gather qualitative and quantitative performance data from 66 completed water and wastewater pipeline projects. Performance data analysis was conducted to provide performance benchmarks for CMAR projects and to compare the performance of CMAR and DBB.
This study provides the first CMAR performance benchmark for pipeline engineering and construction projects. The results span across seven metrics in four performance areas (cost, schedule, project change, and communication). Pipeline projects delivered using CMAR have a median cost and schedule growth of -5% and 5.10%, respectively. These results are significantly improved from DBB baseline performance shown in other industries. To verify this, a statistical analysis was done to compare the cost and schedule performance of CMAR to similar DBB pipeline projects. The results show that CMAR pipeline projects are being delivered with 6.5% less cost growth and with 12.5% less schedule growth than similar DBB projects, providing owners with increased certainty when delivering their pipeline projects.
The dissertation fills this gap in knowledge by performing the first quantitative analysis of CMAR performance on pipeline engineering and construction projects. This study’s two research objectives are:
(1) Develop a CMAR baseline of commonly measured project performance metrics
(2) Statistically compare the cost and schedule performance of CMAR to that of the traditional DBB delivery method
A thorough literature review led to the development of a data collection survey used in conjunction with structured interviews to gather qualitative and quantitative performance data from 66 completed water and wastewater pipeline projects. Performance data analysis was conducted to provide performance benchmarks for CMAR projects and to compare the performance of CMAR and DBB.
This study provides the first CMAR performance benchmark for pipeline engineering and construction projects. The results span across seven metrics in four performance areas (cost, schedule, project change, and communication). Pipeline projects delivered using CMAR have a median cost and schedule growth of -5% and 5.10%, respectively. These results are significantly improved from DBB baseline performance shown in other industries. To verify this, a statistical analysis was done to compare the cost and schedule performance of CMAR to similar DBB pipeline projects. The results show that CMAR pipeline projects are being delivered with 6.5% less cost growth and with 12.5% less schedule growth than similar DBB projects, providing owners with increased certainty when delivering their pipeline projects.
ContributorsFrancom, Tober C (Author) / Ariaratnam, Samuel (Thesis advisor) / El Asmar, Mounir (Thesis advisor) / Bearup, Wylie (Committee member) / Arizona State University (Publisher)
Created2015
Description
Regulatory agencies, such as the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH), recognize that decisions regarding occupational health are often economically driven, with worker health only a secondary concern (Ruttenberg, 2014). To investigate the four National Occupational Research Agenda (NORA) long-standing health concerns—welding fumes, crystalline silica, noise, and musculoskeletal disorders—a mixed methods research is conducted. Fourfold structuration, a holistic communication process with roots in indigenous/ancient knowledge, is used to organize data and facilitate making tangible relationships of health to productivity and profits that are abstract and often stated by industries, such as construction, as difficult to quantify. From both construction trade worker and occupational health and safety expert interviews data/codes are developed. For the qualitative method, the codes are organized into a constructivist grounded theory depicting the construction industry with regard to its foundation – profits. A theoretical exercise translating the qualitative codes into potential productivity losses is presented as a way for quantifying the abstract relationships of health to productivity. For the quantitative study, the data/codes are used to develop a comprehensive list of practices, barriers to, and catalysts for addressing health in construction. A significant quantitative finding is that occupational health and safety (OSH) experts are not traditionally involved at the highest levels of the OSHA Hierarchy of Controls, where the greatest opportunity to prevent exposure to health hazards is possible. Organized via a holistic framework, this research emphasizes our primary responsibility to each other as highlighted in recent NIOSH worker health agendas.
ContributorsTello, Linda Marguerite (Author) / Grau, David (Thesis advisor) / Koro-Ljungberg, Mirka (Committee member) / Hanemann, Michael (Committee member) / Chong, Oswald (Committee member) / Arizona State University (Publisher)
Created2017
Description
Water utilities across the United States are facing numerous challenges, such as limited funding and increasing project complexity, in constructing and upgrading their aging infrastructure. One innovative method to overcome these challenges is through the use of alternative project delivery methods (APDM), such as construction management at-risk (CMAR) and design-build (DB). Previous research has shown that APDM have the potential to deliver higher performing water infrastructure projects when compared to the traditional design-bid-build (DBB) method. However, there is a need to further examine APDM practices and develop tools that may support utilities in the delivery of their APDM water infrastructure projects. This study fills the knowledge gap by conducting several studies that may support public and private utilities in improving the delivery of their APDM water infrastructure projects. First, APDM implementation practices for water infrastructure projects are identified by assessing the state of practice, particularly during project procurement and execution. Second, DB project administration best practices are determined to support utilities seeking to add DB to their organization’s project delivery toolbox. Third, a pioneering web-based project delivery method decision-support tool was developed to aid utilities in selecting the appropriate delivery method for their water project. Finally, project-specific factors and attributes that impact project delivery performance are investigated through exploratory modeling and analysis. The study collected data on 75 completed treatment plant projects, conducted interviews with ten utilities that successfully deliver their water projects using DB, and worked closely with several industry experts through industry workshops and panels. Key findings related to water infrastructure project delivery revealed in this study included: (1) guaranteed maximum price (GMP) is the preferred compensation type for APDM projects; (2) utilities statistically having the lowest comfort level with delivering CMAR projects; (3) qualifications-based procurement is an effective DB project delivery practice; (4) the identification of 13 key project delivery method selection factors; and (5) the three highest predictors that impact unit cost performance are project complexity, project team chemistry and communication, and project size.
ContributorsFeghaly, Jeffrey (Author) / El Asmar, Mounir (Thesis advisor) / Ariaratnam, Samuel (Thesis advisor) / Bearup, Wylie (Committee member) / Arizona State University (Publisher)
Created2020