Download or read book Experimental and Analytical Seismic Studies of a Four span Bridge System with Innovative Materials written by Carlos Alonso Cruz-Noguez and published by . This book was released on 2010 with total page 1524 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of a multi-university project utilizing the NSF Network for Earthquake Engineering Simulation (NEES), a quarter-scale model of a four-span bridge incorporating plastic hinges with different advanced materials was tested to failure on the three shake table system at the University of Nevada, Reno (UNR). The bridge was the second test model in a series of three 4-span bridges, with the first model being a conventional reinforced-concrete (RC) structure. The purpose of incorporating advanced materials was to improve the seismic performance of the bridge with respect to two damage indicators: (1) column damage and (2) permanent deformations. The goals of the study presented in this document were to (1) evaluate the seismic performance of a 4-span bridge system incorporating SMA/ECC and built-in rubber pad plastic hinges as well as post-tensioned piers, (2) quantify the relative merit of these advanced materials and details compared to each other and to conventional reinforced concrete plastic hinges, (3) determine the influence of abutment-superstructure interaction on the response, (4) examine the ability of available elaborate analytical modeling techniques to model the performance of advanced materials and details, and (5) conduct an extensive parametric study of different variations of the bridge model to study several important issues in bridge earthquake engineering. The bridge model included six columns, each pair of which utilized a different advanced detail at bottom plastic hinges: shape memory alloys (SMA), special engineered cementitious composites (ECC), elastomeric pads embedded into columns, and post-tensioning tendons. The design of the columns, location of the bents, and selection of the loading protocol were based on pre-test analyses conducted using computer program OpenSees. The bridge model was subjected to two-horizontal components of simulated earthquake records of the 1994 Northridge earthquake. Over 340 channels of data were collected. The test results showed the effectiveness of the advanced materials in reducing damage and permanent displacements. The damage was minimal in plastic hinges with SMA/ECC and those with built-in elastomeric pads. Conventional RC plastic hinges were severely damaged due to spalling of concrete and rupture of the longitudinal and transverse reinforcement. Extensive post-test analytical studies were conducted and it was determined that a computational model of the bridge that included bridge-abutment interaction using OpenSees was able to provide satisfactory estimations of key structural parameters such as superstructure displacements and base shears. The analytical model was also used to conduct parametric studies on single-column and bridge-system response under near-fault ground motions. The effects of vertical excitations and transverse shear-keys at the bridge abutments on the superstructure displacement and column drifts were also explored.
Download or read book Experimental and Analytical Seismic Studies of a Four span Bridge System with Composite Piers written by Fatemeh Kavianipour and published by . This book was released on 2013 with total page 1350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Funded by the National Science Foundation through the Network for Earthquake Engineering Simulation (NEES) research program, a major multi-university research project has been in progress at the University of Nevada, Reno. This study describes the study of one of the three large-scale bridge models that were tested to failure on three shake tables system. This model was supported on fiber-reinforced polymer (FRP) composite piers implementing accelerated bridge construction (ABC) techniques. The bridge was a quarter scale model of a 4-span bridge with continuous reinforced concrete superstructure and a drop cap, two-column pier design. Each pier utilized different unconventional FRP details. The purpose of using these innovative details was to improve the seismic performance of the bridge. The first pier consisted of cast-in-place concrete-filled glass FRP tubes with ±55 degree fibers. The second pier consisted of two segmental reinforced concrete columns wrapped with layers of unidirectional carbon FRP sheets to provide confinement and shear reinforcement. Only nominal hoops were used to hold the longitudinal reinforcement, as FRP jacket and tube were sufficient in providing confinement and shear required reinforcement. The third pier had the same configuration as that of pier 1 but the columns and footing were precast. The top connections in piers 1 and 3 consisted of pipe-pin joints to facilitate ABC and provide hinge behavior. The objectives of the study presented in this document were to evaluate the biaxial seismic performance of this bridge system incorporating composite piers, investigate the performance of each detail and compared them to each other and to conventional ones, determine the influence of abutment-superstructure interaction on the response, assess the performance of a bridge model incorporating ABC techniques, evaluate sufficiency of analytical modeling of the performance of composite material and details, and to conduct parametric study of different variations of the bridge model to study the effect of several important factors such as near-fault earthquake effects and the variations in the configuration of the bridge model. large-scale 4-span bridge model was designed, constructed, and subjected to simulated earthquake loading on three shake tables. The simulated shake table motions were the modified 1994 Northridge, CA ground motion recorded in Century City and were applied to the bridge model in ten runs with increasing amplitudes. Over 380 channels of data were collected. Compared to conventional reinforced concrete bridges, experimental results showed superior performance under extreme seismic loading even under lateral drift ratios exceeding 9%. Extensive post-test analytical studies were conducted and it was determined that a computational model of the bridge that included bridge-abutment interaction using OpenSees was able to provide satisfactory estimations of key structural response parameters such as superstructure displacements. The analytical model was also used to conduct parametric studies on response of the bridge model and its variations under near-fault excitations. The effects of changing the column section properties were also explored. It was found that concrete-filled FRP tube piers and CFRP wrapped post-tensioned segmental piers reduce residual displacements compared to their conventional reinforced concrete counter parts even under impulsive near-fault motions.
Download or read book Next Generation of Bridge Columns for Accelerated Bridge Construction in High Seismic Zones written by Mostafa Tazarv and published by . This book was released on 2014 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Longitudinal bar debonding allowed spread of yielding and prevented premature failure of reinforcements in UHPC-filled duct connections and grouted coupler column pedestal. The SMA-reinforced ECC column showed superior seismic performance compared to a conventional column in which the plastic hinge damage was limited to only ECC cover spalling even under 12% drift ratio cycles. The column residual displacements were 79% lower than CIP residual displacements on average due to the superelastic NiTi SMA longitudinal reinforcement, and higher base shear capacity and higher displacement capacity were observed. The analytical modeling methods were simple and sufficiently accurate for general design and analyses of precast components proposed in the present study. The proposed symmetrical material model for reinforcing NiTi superelastic SMA was found to be a viable alternative to the more complex asymmetrical model.
Download or read book Bridge Maintenance Safety Management Resilience and Sustainability written by Fabio Biondini and published by CRC Press. This book was released on 2012-06-21 with total page 4119 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge Maintenance, Safety, Management, Resilience and Sustainability contains the lectures and papers presented at The Sixth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2012), held in Stresa, Lake Maggiore, Italy, 8-12 July, 2012. This volume consists of a book of extended abstracts (800 pp) Extensive collection of revised expert papers on recent advances in bridge maintenance, safety, management and life-cycle performance, representing a major contribution to the knowledge base of all areas of the field.
Download or read book Risk Based Bridge Engineering written by Khaled Mahmoud and published by CRC Press. This book was released on 2019-08-20 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Risk-based engineering is essential for the efficient asset management and safe operation of bridges. A risk-based asset management strategy couples risk management, standard work, reliability-based inspection and structural analysis, and condition-based maintenance to properly apply resources based on process criticality. This ensures that proper controls are put in place and reliability analysis is used to ensure continuous improvement. An effective risk-based management system includes an enterprise asset management or resource solution that properly catalogues asset attribute data, a functional hierarchy, criticality analysis, risk and failure analysis, control plans, reliability analysis and continuous improvement. Such efforts include periodic inspections, condition evaluations and prioritizing repairs accordingly. This book contains select papers that were presented at the 10th New York City Bridge Conference, held on August 26-27, 2019. The volume is a valuable contribution to the state-of-the-art in bridge engineering.
Download or read book Reliable Engineering Computing written by and published by Research Publishing Service. This book was released on with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analytical and Experimental Studies on the Seismic Response of Short Span Reinforced Concrete Bridges written by Spiridon Vrontinos and published by . This book was released on 1994 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural Seismic Design Optimization and Earthquake Engineering Formulations and Applications written by Plevris, Vagelis and published by IGI Global. This book was released on 2012-05-31 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Throughout the past few years, there has been extensive research done on structural design in terms of optimization methods or problem formulation. But, much of this attention has been on the linear elastic structural behavior, under static loading condition. Such a focus has left researchers scratching their heads as it has led to vulnerable structural configurations. What researchers have left out of the equation is the element of seismic loading. It is essential for researchers to take this into account in order to develop earthquake resistant real-world structures. Structural Seismic Design Optimization and Earthquake Engineering: Formulations and Applications focuses on the research around earthquake engineering, in particular, the field of implementation of optimization algorithms in earthquake engineering problems. Topics discussed within this book include, but are not limited to, simulation issues for the accurate prediction of the seismic response of structures, design optimization procedures, soft computing applications, and other important advancements in seismic analysis and design where optimization algorithms can be implemented. Readers will discover that this book provides relevant theoretical frameworks in order to enhance their learning on earthquake engineering as it deals with the latest research findings and their practical implementations, as well as new formulations and solutions.
Download or read book Seismic Performance of Reinforced Concrete Bridges Allowed to Uplift During Multi Directional Excitation written by Andres Oscar Espinoza and published by . This book was released on 2011 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract Seismic Performance of Reinforced Concrete Bridges Allowed to Uplift During Multi-Directional Excitation by Andres Oscar Espinoza Doctor of Philosophy in Engineering - Civil and Environmental Engineering University of California, Berkeley Professor Stephen A. Mahin, Chair The behavior of bridges subjected to recent moderate and large earthquakes has led to bridge design detailed for better seismic performance, particularly through wider bridge foundations to handle larger expected design forces. Foundation uplift, which is not employed in conventional bridge design, has been identified as an important mechanism, in conjunction with structural yielding and soil-structure interaction that may dissipate energy during earthquakes. Preventing uplift through wider foundations looks past the technical and economical feasibility of allowing foundation uplift during seismic events. The research presented in this thesis is part of a larger experimental and analytical investigation to develop and validate design methods for bridge piers on shallow foundations allowed to uplift during seismic events. Several analytical and some experimental studies have been performed to assess rocking and or uplift of shallow foundation systems, however they have evaluated systems with a limited range of footing dimensions and seismic excitations. As such, there is an uncertainty in the information needed to base a performance evaluation and develop design methods. The purpose of this study is to investigate, through experimental and analytical studies, the seismic performance of uplifting bridge piers on shallow foundations when considering different ground motions and footing dimensions. As well as to identify key differences in performance evaluation criteria for conventional and uplifting bridge pier systems. The experimental study dynamically tested a single reinforced concrete bridge column specimen with three adjustable footing configurations grouped by footing dimension, and tested for various combinations of one, two, and three components of seismic excitation. Groups one and two evaluated uplifting systems where the column was limited to elastic loading levels while group three considered inelastic column loading levels. All test groups remained stable and exhibited some rocking and or uplift during testing. Analytical models were developed and validated using the experimental testing results to predict local and global footing and column response. Reliable estimates of forces and displacements during elastic and inelastic response were achieved. To assess the seismic performance of a range of bridge pier systems allowed to uplift a parametric investigation using the validated analytical models was performed in which the column was modeled per conventional design criteria to ensure adequate strength and flexural ductility. The parameters varied include footing width, ground motion excitation, and elastic or inelastic column response. Response of the uplifting bridge pier systems was found to be sensitive to the structural periods, magnitude of excitation, and footing width.
Download or read book Bridge Maintenance Safety Management Life Cycle Sustainability and Innovations written by Hiroshi Yokota and published by CRC Press. This book was released on 2021-04-20 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge Maintenance, Safety, Management, Life-Cycle Sustainability and Innovations contains lectures and papers presented at the Tenth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2020), held in Sapporo, Hokkaido, Japan, April 11–15, 2021. This volume consists of a book of extended abstracts and a USB card containing the full papers of 571 contributions presented at IABMAS 2020, including the T.Y. Lin Lecture, 9 Keynote Lectures, and 561 technical papers from 40 countries. The contributions presented at IABMAS 2020 deal with the state of the art as well as emerging concepts and innovative applications related to the main aspects of maintenance, safety, management, life-cycle sustainability and technological innovations of bridges. Major topics include: advanced bridge design, construction and maintenance approaches, safety, reliability and risk evaluation, life-cycle management, life-cycle sustainability, standardization, analytical models, bridge management systems, service life prediction, maintenance and management strategies, structural health monitoring, non-destructive testing and field testing, safety, resilience, robustness and redundancy, durability enhancement, repair and rehabilitation, fatigue and corrosion, extreme loads, and application of information and computer technology and artificial intelligence for bridges, among others. This volume provides both an up-to-date overview of the field of bridge engineering and significant contributions to the process of making more rational decisions on maintenance, safety, management, life-cycle sustainability and technological innovations of bridges for the purpose of enhancing the welfare of society. The Editors hope that these Proceedings will serve as a valuable reference to all concerned with bridge structure and infrastructure systems, including engineers, researchers, academics and students from all areas of bridge engineering.
Download or read book Assessment of an Earthquake Resilient Bridge with Pretensioned Rocking Columns written by Islam Mohamed Mantawy and published by . This book was released on 2016 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt: The seismic performance of a new bridge system is studied, tested and improved. The new bridge system: 1) reduces onsite construction time by using precast components, 2) eliminates major earthquake damage by utilizing rocking column and confinement of the column ends with a steel tube, and 3) maintains the system functionality after a strong earthquake by minimizing residual drift through the use of prestressing strands in the columns. Furthermore, it uses only conventional materials. The shaking table performance of a quarter-scale, two-span bridge constructed using the new system was compared with that of a conventional cast-in-place bridge with similar geometry tested in 2005. The new bridge system was constructed in about 20% of the time needed for the conventional cast-in-place system. In the tests, the conventional bridge suffered major concrete cracking and spalling, whereas in the new system, damage to the concrete was only cosmetic. In the conventional bridge, the longitudinal bars buckled and both the longitudinal and spiral reinforcement fractured, whereas in the new system the damage to the reinforcement was limited to longitudinal bar fracture, and that occurred only under excitations larger than the design level motion. The residual drift of the new system was essentially zero for all motions, whereas one of the exterior bents of the conventional bridge was so badly damaged and out of plumb that some of the supplemental mass on the bridge had to be removed and testing was stopped shortly thereafter. The only substantial damage that the new bridge system experienced was longitudinal reinforcing fracture. Therefore, ways to delay fracture were developed analytically. Reinforcement fractures were audible during the shaking table tests of the pretensioned rocking system. Reinforcement fractures were estimated in three ways using: 1) audio recorded during each test, 2) measured rotations at column ends and 3) analytical models, which included a fatigue material. This analytical model was then used to explore methods to improve the performance of the system by delaying reinforcement fracture. The analytical parametric studies on the scaled model showed that increasing the bar size and the locally debonded length of the reinforcement were both effective strategies to reduce and delay bar fractures. For the shaking table experimental model configuration, the analytical model showed that increasing the longitudinal bars by one size and increasing the debonded length by 44% would delay bar fracture until an excitation 67% larger than the excitation where reinforcing bars first fractured in the physical experiment. The parametric study also was conducted for a prototype bent; this recommended values for longitudinal bar size, debonded lengths for longitudinal bars and effective prestressing for prestressing strands to delay the fracture of the longitudinal bars and the yielding of the prestressing strands until after the 150% design level motion.
Download or read book Wind and Seismic Effects written by United States-Japan Cooperative Program in Natural Resources. Panel on Wind and Seismic Effects. Joint Meeting and published by . This book was released on 1991 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Vibration Analysis for Civil Structures written by Jian Zhang and published by CRC Press. This book was released on 2020-11-04 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental Vibration Analysis for Civil Structures: Testing, Sensing, Monitoring, and Control covers a wide range of topics in the areas of vibration testing, instrumentation, and analysis of civil engineering and critical infrastructure. It explains how recent research, development, and applications in experimental vibration analysis of civil engineering structures have progressed significantly due to advancements in the fields of sensor and testing technologies, instrumentation, data acquisition systems, computer technology, computational modeling and simulation of large and complex civil infrastructure systems. The book also examines how cutting-edge artificial intelligence and data analytics can be applied to infrastructure systems. Features: Explains how recent technological developments have resulted in addressing the challenge of designing more resilient infrastructure Examines numerous research studies conducted by leading scholars in the field of infrastructure systems and civil engineering Presents the most emergent fields of civil engineering design, such as data analytics and Artificial Intelligence for the analysis and performance assessment of infrastructure systems and their resilience Emphasizes the importance of an interdisciplinary approach to develop the modeling, analysis, and experimental tools for designing more resilient and intelligent infrastructures Appropriate for practicing engineers and upper-level students, Experimental Vibration Analysis for Civil Structures: Testing, Sensing, Monitoring, and Control serves as a strategic roadmap for further research in the field of vibration testing and instrumentation of infrastructure systems.
Download or read book Federally Coordinated Program of Research and Development in Highway Transportation written by and published by . This book was released on 1982 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resilient Earthquake resistant Bridges Designed for Disassembly written by Sebastián Varela Fontecha and published by . This book was released on 2016 with total page 1706 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ordinary reinforced concrete (RC) highway bridges complying with current seismic design provisions are expected to be severely damaged during a strong earthquake. Previous earthquakes have shown that closing a bridge for repair or having to replace the bridge because of extensive damage and permanent tilting of the structure can be very costly and detrimental to the transportation in major urban areas. When RC bridges reach their useful life, only a small portion of the concrete and steel debris from demolition is recycled, while the rest goes to landfills. This is not the ideal end-of-life for construction materials because their extraction and manufacturing emits greenhouse gases, consumes energy, and depletes natural resources, all of which are negatively affecting the environment. In an attempt to link seismic resistance and resiliency with sustainability in bridge engineering, a new generation of earthquake-resistant and resilient highway bridges designed for disassembly (DfD) was developed in this study for the first time. The global objective of developing these bridges is to (1) minimize the economic impact of losing bridge functionality after strong earthquakes, and (2) reduce the environmental impact of producing new construction materials. The new bridge concept first involved the development and shake-table testing of three 1/4-scale deconstructible column models under simulated strong near-fault motions from the 1994, Northridge, California earthquake. The models were then disassembled and inspected, and subsequently reassembled and retested. Three replaceable plastic hinge elements and connections were developed incorporating advanced materials such as engineered cementitious composite (ECC), shimmed flexural rubber bearings, Nickel-Titanium (NiTi) and Copper-Aluminum-Manganese (CAM) super elastic shape memory alloy (SMA) bars, and prefabricated fiber-reinforced polymer (FRP) tubes were integrated in the column models. An additional cast-in-place column combining ECC and CAM SMA was designed and tested to develop an insight into the behavior of large-scale CAM-reinforced members under seismic loading before this type of SMA was adopted in the replaceable plastic hinge elements. The tests confirmed the feasibility of DfD columns. The experimental investigation was then complemented by analytical studies in OpenSees, in which analytical models were developed to replicate the measured response of the column models. To determine the feasibility of the columns within a bridge system, a 1/4-scale, three-bent, two-span bridge model was designed, constructed and tested under simulated near-fault earthquakes on three shake-tables. Upon successful performance of the original bridge, the bridge model was disassembled, all the components were inspected, and the bridge was subsequently reassembled and retested. Extensive evaluations of the behavior of the columns, connections, plastic hinges, as well as the entire system were made during the experimental investigation. The performance of the reassembled bridge demonstrated the feasibility of the proposed elements in a bridge system. Analytical studies using OpenSees were also conducted to develop a baseline for future studies.
Download or read book Correlation of Experimental and Analytical Studies for the Seismic Response of Highway Bridges written by Kazuhiko Kawashima and published by . This book was released on 1975 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Analytical Investigations on the Effects of Live Load on the Seismic Performance of a Highway Bridge written by Hartanto Wibowo and published by . This book was released on 2013 with total page 1572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current bridge design specifications have few requirements concerning the inclusion of live load in the seismic design of bridges for perhaps two reasons: 1) the likelihood of the full design live load occurring at the same time as the design earthquake is deemed to be very low, and 2) adverse behavior in an earthquake due to live load has not been observed in practice. However, with increasing congestion in major cities, the occurrence of the design earthquake at the same time as the design live load is now more likely than in the past. But little is known about the effect of live load on seismic response and this dissertation describes an experimental and analytical project that investigates this behavior. The experimental work included shake table testing of a 2/5th -scale model of a three-span, horizontally curved, steel girder bridge loaded with a series of representative trucks. The model spanned four shake tables each synchronously excited with scaled ground motions from the 1994 Northridge Earthquake. Observations from the experimental work show the presence of the live load had a beneficial effect on performance of this bridge, but this effect diminished with increasing amplitude of shaking. During the design earthquake, the bridge with live load was essentially elastic whereas the bridge without live load suffered some yielding and the maximum displacement at the top of the column was approximately 35% less in the live load case. Parameters used to measure performance included column displacement, abutment shear force, and degree of concrete spalling in the plastic hinge zones. Results obtained from nonlinear finite element analyses of the bridge with and without trucks confirm this behavior, that live load reduces the dynamic response of the bridge. The most likely explanation for this phenomenon is that the trucks act as a set of nonlinear multiple mass dampers, a variation of tuned mass dampers that are known to be effective at controlling wind vibrations in buildings. Parameter studies have also been conducted and show the above beneficial effect is generally true for other earthquake ground motions and vehicles with different dynamic properties. Exceptions exist, but adverse effects are usually within 10-15% of the no-live load case. Although the above results were obtained for a particular bridge, earthquake loading, and vehicle configuration, they may also apply to other bridges. Further work is required to confirm this observation.
