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Publication Post-Fire Damage Inspection of Concrete Structures Phase II(2023-02) Gerasimidis, Simos; Civjan, ScottIn general, tunnels are designed with an abundance of safety regarding structural integrity, however, there can be uncertainty related to structural performance after a fire event. The residual condition of a tunnel after a fire is dependent on fire intensity and duration. The goal of this study is to correlate visual and material characteristics of structural and nonstructural components of tunnels with fire temperature and exposure time. This can be further related to the residual capacity of structural members in a tunnel, providing insight into safety and overall functionality. Experimental results show that the visual response of materials with heat exposure is variable and dependent on a number of factors. A wide range of materials were studied to establish a well-versed collection of data that may be used in a post-fire inspection. In addition, mechanical testing of three configurations of structural slabs exposed to different heating regimens was conducted. The influence of heat on a structural member may be complex, and was found to be minimal for the heating regimens and loading procedures applied. This work can serve as an aid for post-fire investigation by providing methods to estimate fire intensity and duration through visual observation and mechanical testing.Publication The Current State of Practice of Building Information Modeling(2023-08) Brooks, Kevin; Gerasimidis, Simos; Civjan, ScottBuilding information modeling is a combination of technology and processes that has made significant changes to the architecture, engineering, construction, and operations industries. By enabling the visualization of project elements and their data in 3D, it allows for a reduction in unbudgeted changes, increased collaboration and efficiency, and numerous other capabilities that are implemented to varying degrees throughout the industry. This study aims to evaluate perspectives on building information modeling from stakeholders in academia, architecture, engineering, construction, and operations, as well as the perspectives of software vendors, to elucidate a comprehensive current state of practice of building information modeling. Further, it seeks to make recommendations for building information modeling implementation at the Massachusetts Bay Transit Authority with the intent of increasing organizational efficiency and, in the future, leveraging asset data for facility management purposes.Publication Improved Load Rating Procedures for Deteriorated Unstiffened Steel Beam Ends(2024-01) Provost, Aidan; Tzortzinis, Georgios; Islam, Mohammad Shahrukh; Gerasimidis, Simos; Breña, Sergio F.This report contains the contents of the project to enhance load rating methods for assessing corroded unstiffened beam ends for the six New England States. The first task of the project was to collect and compile inspection reports information provided by DOTs within New England. The research team was able to carefully identify trends and patterns in the data, which was used to determine the most common scenarios of corrosion encountered in bridges within New England States. Following this task, corroded bridge girder specimens were selected from existing structures to be documented and experimentally tested in the structural testing facility at UMass Amherst. The specimens were also computationally analyzed for their section loss and remaining capacity. The final goal of this project was to evaluate the load rating procedures across all of the New England States and recommend updates to the procedures based on our experimental and analytical results.Publication Development of Comprehensive Inspection Protocols for Deteriorated Steel Beam Ends(2022-03) Tzortzinis, Georgios; Breña, Sergio F.; Gerasimidis, SimosRecent research has developed new improved procedures that accurately describe the remaining loadcarrying capacity of these deteriorated members. These new procedures are based on computational simulations and experimental testing of real deteriorated beams. The outcome of a recently completed research project (“Development of Load Rating Procedures for Deteriorated Steel Beam Ends,” completed July 2019) has found new parameters that are extremely important when assessing the residual capacity of the bridge and the load rating procedure. Examples of these parameters include the out-of-plane imperfection of the beam web, the surface area of corrosion, and others. Currently, inspectors are not aware of the new findings and these important parameters, and they have no clear guidance on what and how to measure when inspecting a deteriorated beam end. Drawing on the recent findings made while developing new load rating procedures, the project at hand first documents the current state of practice of beam end inspections, then explores new technological solutions for improvement of these inspection techniques using LiDAR and unmanned aircraft systems (drones), and finally performs preliminary analysis of a bridge system.Publication Feasibility of 3D Printing Applications for Highway Infrastructure Construction and Maintenance(2022-05) Hart, John A.; Chen, Wen; Quinlan, Haden; Gerasimidis, SimosIn recent years there has been a significant increase of the interest in additive manufacturing (AM; also frequently referred to as 3D printing), yet AM is largely unexplored within infrastructure projects. By harnessing the new capabilities of AM, researchers have managed to access unprecedented new design capabilities and operational flexibility (e.g., on-demand, toolfree production). This revolutionary progress, however, has not been reflected in applications focused on transportation infrastructure. This project explores AM innovations and their capabilities related to transportation infrastructure and as a potential future resource to assist MassDOT Highway Division’s ongoing rehabilitation of bridge, tunnel, and highway structures, as well as classic recurring maintenance activities. The project’s main research objective is to connect the additive manufacturing research community with MassDOT to explore additive repair techniques as well as individual component manufacturing for the highway and construction sector purposes. The project also aims at drafting MassDOT business process recommendations for AM technologies.Publication Post-Fire Damage Inspection of Concrete Structures(2021-04) Gerasimidis, Simos; Civjan, ScottAlthough concrete tunnel structures can lose strength and long-term durability due to fire, literature on the remaining capacity of structures after fire events is scattered, and few published post-fire inspection protocols exist, especially for tunnel structures. This project investigates the deleterious effects of fire on concrete tunnel structures and how the extent and degree of fire damage can be assessed, with the goal of developing a rapid inspection protocol/checklist for inspectors to assess the relative safety of a tunnel structure after fire. The project includes an extensive literature review, covering published standards, technical reports, academic papers, and a survey of post-fire inspection practices at other state DOTs and transit organizations. Topics include residual mechanical properties of concrete, steel, and concrete/steel bond after fire; residual strength and stiffness of structural members after fire; existing inspection tools and methods for assessing concrete structures after fire; and repair methods for fire-damaged concrete structures. Preliminary experimental testing outcomes are presented, including setup of a new heat system; procurement of sample specimens for testing; thermal and physical testing of specimens; and evaluation of results. Finally, recommendations for a second phase of experimental testing are presented.Publication Development of Load Rating Procedures for Deteriorated Steel Beam Ends(2019-09) Gerasimidis, Simos; Breña, Sergio F.This study focuses on the current strength evaluation policies for strength assessment of corroded steel girders and investigates potential improvements based on real corrosion data. The research work included in this report has three phases. First, the current deterioration condition of steel bridges is studied through MassDOT inspection reports of bridges with beam end corrosion. The topology and the extent of the phenomenon are recorded from the reports and the gathered data are processed to define the most common corrosion patterns. Second, full scale experimental testing of naturally corroded girders is performed. The beams are obtained from bridge demolition projects across the Commonwealth of Massachusetts and tested in the Brack lab at UMass Amherst. Based on the experimental test results, a numerical finite element model is appropriately calibrated to predict the failure load of corroded beam ends. Finally, combining the new corrosion patterns identified during the first part of the work with finite element modeling, an extensive parametric analysis is performed. Based on the numerical outcome, the current procedures are evaluated and improvements are proposed through a new set of equations. The report includes many important findings regarding the behavior of corroded beam ends and discusses the limitations of this study and potential future research work.Publication Improved Load Rating Procedures for Deteriorated Steel Beam Ends with Deteriorated Stiffeners(2021-09) Tzortzinis, Georgios; Breña, Sergio F.; Gerasimidis, SimosThis study of Improved Load Rating Procedures for Deteriorated Steel Beam Ends with Deteriorated Stiffeners was undertaken as part of the Massachusetts Department of Transportation (MassDOT) Research Program. This program is funded with Federal Highway Administration (FHWA) State Planning and Research (SPR) funds. Through this program, applied research is conducted on topics of importance to the Commonwealth of Massachusetts transportation agencies. The national highway system consists of approximately 46,000 (1) structurally deficient bridges, with corrosion as a common cause for steel viaduct deterioration. This condition can be primarily attributed to malfunctioning deck expansion joints, which fail to prevent water or deicing mixtures from penetrating into the bearing area. The buildup of this runoff triggers a corrosive process that significantly varies in topology and intensity, leading in many cases to severe section loss that affects the residual bearing capacity of the beam and, consequently, of the whole bridge. This research focuses on simple span girders with plate girders and uses real corrosion data to assess the current bridge manual procedures.Publication Ultra-High-Performance Concrete Reinforced with Multi-Scale Hybrid Fibers and Its Durability-Related Properties(2023-01-01) Wei, Jianqiang; Brena, Sergio; Ritchie, Cameron; Bhaskar More, HiteshDue to its excellent mechanical properties, dense microstructure, low permeability, ease of placement and volume stability, ultra-high performance concrete (UHPC) is considered the next-generation structural concrete and is increasingly used in transportation infrastructure. While previous research efforts generated valuable results, to achieve the desired performance, UHPC needs to be well formulated with precise and optimized quantities of cementitious materials, fillers, fine aggregate, water, chemical admixtures, and fibers. In addition, the mixture design of UHPC and its correlation with the performance evolution under different curing conditions remain unclear, and there exist critical significant gaps in understanding the efficiency of fibers and mixture design on the properties of UHPC, especially the mechanical and durability-related performance. Massachusetts Department of Transportation (MassDOT) is exploring multiple infrastructure applications that can incorporate UHPC, including joints, overlays, repairs, rehabilitation, and bridge beam fabrication. This project aims to develop UHPC mix design formulations that can be implemented at ready-mix batching plants or precast/prestressed concrete fabrication facilities by identifying and maximizing the roles of fibers and additives in enhancing mechanical and durability-related properties. Four fiber-reinforced mixes and seven UHPC mixes with different fibers were investigated and a UHPC mix for large-scale batching and field applications was recommended.Publication Revised Load Rating Procedures for Deteriorated Prestressed Concrete Beams(2023-01-01) Stripsky, Alex; Brena, Sergio F; Boakye, Jessica; Civjan, Scott A; Gerasimidis, SimosThe first prestressed concrete bridge in the United States was built in the early 1950s. Since then, several typical sections have been developed for use in bridge construction including I-beams, deck slabs, box beams, double tees, etc. In bridges under aggressive environments, corrosion deterioration of prestressing strands and stirrups has occurred creating challenges associated with determining the strength of deteriorated existing bridge sections. The MassDOT LRFD Bridge Manual includes provisions to estimate strength of corrosion deteriorated prestressed concrete box beams allowing engineers to calculate the load rating of these types of bridges. The provisions are based on the observed condition of the bridge, particularly with regard to estimates of strand area reductions to estimate residual strength. In bridges with adjacent box beams or deck slabs, corroded reinforcement is difficult to identify because only the top and bottom surfaces of the superstructure elements are accessible. The goals of this research are to evaluate the existing strength calculation procedures and to provide recommendations on how to properly evaluate the reduction in strand area based on the observed condition of the bottom surface of the prestressed box or deck beams.Publication Construction and Materials Best Practices for Concrete Sidewalks: Phase II - Long-Term Performance and Hot Weather Placement Effects(2023-01-01) Peterman, Kara; Brena, Sergio; Rudraraju, Likhitha; Shea, BrianThis report summarizes the investigation of construction practices and materials to develop durable concrete sidewalks which can resist scaling damage caused by exposure to freezing environment and deicer application. Over 16 months, a field study accompanied by laboratory testing was conducted to identify factors that affect the performance and durability of sidewalks. The variables considered for the study are concrete mix design, placement and finishing practices, curing methods, and deicer application. The placement of the sidewalks took place in late July 2021, to investigate the impact of hot weather concreting practices on the performance of sidewalks. Forty-eight sidewalk panels were placed behind Robert Brack Structural Engineering Laboratory at University of Massachusetts Amherst (UMass). During the sidewalk placement, cylinders and rectangular prisms were placed for laboratory testing. Thirty-two rectangular prisms were subjected to same curing method as the corresponding sidewalks for scaling resistance test in laboratory via BNQ NQ 2621-900. The results of this study indicate that mixture design formulation, curing method, de-icing method, and temperature based concreting practices impact the performance of scaling in concrete sidewalks. Recommendations incorporating these variables are presented in this report with accompanying testing standards and procedures.Publication Impact of Edge Distance on Hysteretic Behavior of Fiber-Cement-Board Cold-Formed Steel Connections(2023-01-01) Ariana, Sheila; Peterman, KaraSeismic design of cold-formed steel shear walls is constantly evolving due to ever-growing interest in the CFS systems in high seismic zones. Cementitious panels used as sheathing for CFS shear walls and diaphragms can achieve superior strength capacity and fire resistance and are thus increasingly popular in light-framed construction. This study aims to assess the impact of six various edge distances on the performance of CFS studs sheathed with fiber cement boards subjected to cyclic loads. In this report, the results of the 108 specimens are investigated. The experimental specimens are designed to represent a slice of a shear wall and contain two studs sheathed on both sides with two panels. Eight fasteners connect the panels to the studs. Steel thickness, fastener type and fastener edge distance are varied to determine the performance of the connections. In total, 108 specimens are tested via the FEMA 461 cyclic protocol, representing a large suite of experimental data for these connection types. Population statistics are performed on the data to quantify inherent variability in these screws fastened connections. Results will inform national design specifications and provide underlying data to enable design of CFS shear walls and diaphragms sheathed with fiber cement boards.Publication Construction and Materials Best Practice for Concrete Sidewalks(2021-01-01) Brena, Sergio F; Peterman, Kara; Sullivan, RhyanThis report summarizes an 18-month effort to investigate best practices to incorporate into the materials and construction of concrete sidewalks to mitigate surface scaling damage induced by freeze-thaw cycles in the presence of deicing chemicals. The study involved an in-situ experimental study accompanied by laboratory testing and quantitative analyses to determine key factors that impact sidewalk performance and durability. The primary variables considered in the study were concrete mixture design (aggregate/paste optimization, air content, and cementitious material replacements), workmanship (delivery, placement, finishing, curing), and deicing treatment. The collective effort involved participants from construction companies, a concrete producer, academia, testing laboratories, and the Massachusetts Dept. of Transportation (MassDOT). Fifty-four unique sidewalk panels were placed adjacent to the Hopkinton, MA, MassDOT Research and Materials Laboratory. Collectively, the results indicate that sidewalk performance can be controlled though a combination of optimized mix design formulation, proper pre-placement, placement, finishing, curing, cold and hot weather concreting practices, contractor quality control, and department acceptance. Recommendations based on findings and in combination with referenced standards are provided, covering the range of variables studied in this research