Download or read book Characterization of Reinforced Concrete Bridges Using Dynamic Response Measurements for Use in Load Capacity Estimation written by and published by . This book was released on 2005 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. Army Engineer Research and Development Center (ERDC) is leading research efforts for the development of rapid bridge load-capacity assessment tools for the military, otherwise known as Military Load Classification (MLC). These tools may be used in the evaluation of the effects of heavy military-vehicles on civilian bridges and are based, in part, on field tests of concrete bridges. This field testing procedure is aimed at determining the MLC of a bridge by first estimating girder stiffness and considering load distribution effects associated with a test vehicle. This approach, while capable of providing the desired MLC estimate, does not provide an adequate measure of uncertainty or confidence in the estimate, since the field measurement may mask actual damage states in the bridge. Assessing the current condition of a bridge is a key component in the determination of its load-carrying capacity. As a result, tests in which the true condition of the bridge is determined can be useful in assessing the relative uncertainty or even the appropriate confidence level of the MLC estimate. This study describes field testing procedures using ambient, impact, and wave speed techniques on reinforced concrete bridges owned by the Virginia Department of Transportation. The ambient response measurements were used to determine fundamental characteristics including resonant frequencies and mode shapes, while the transient tests were designed to provide some measure of the relative condition that may exist between girders in the bridge. These measurements will supplement other measurements acquired using test vehicles and surveying techniques.

Download or read book Assessment of Bridges written by and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Application of dynamic testing to structural assessment of bridges is considered in this article. Forced vibration tests were conducted before and after installation of new bearings on a reinforced concrete bridge. The aim of the tests was to assess, from the measured dynamic response, the effects of the repairs on the bridge's condition as characterized by its dynamic properties. Frequency response functions, natural frequencies, mode shapes, and viscous damping ratios before and after bearing replacement were compared. The response functions were found to give an indication that some changes have occurred in the bridge. The maximum changes in frequency and damping were about 4% and 21% respectively. The results indicated that the vertical stiffness of the new bearings was not as high as was originally envisaged. Modal analysis techniques were used to compute assessment indices, which were able to indicate one of the abutments affected by the bearing replacement. The approach adopted could potentially be used for the assessment of any engineering structure.

Download or read book Diagnostic and Proof Load Tests on Bridges written by Fikret Necati Catbas and published by Frontiers Media SA. This book was released on 2020-12-11 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.

Download or read book Load Testing of Bridges written by Eva Lantsoght and published by CRC Press. This book was released on 2019-06-19 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Load Testing of Bridges, featuring contributions from almost fifty authors from around the world across two interrelated volumes, deals with the practical aspects, the scientific developments, and the international views on the topic of load testing of bridges. Volume 12, Load Testing of Bridges: Current practice and Diagnostic Load Testing, starts with a background to bridge load testing, including the historical perspectives and evolutions, and the current codes and guidelines that are governing in countries around the world. The second part of the book deals with preparation, execution, and post-processing of load tests on bridges. The third part focuses on diagnostic load testing of bridges. This work will be of interest to researchers and academics in the field of civil/structural engineering, practicing engineers and road authorities worldwide.

Download or read book Bridge Load Rating with Model Updating and Stochastic Analysis of Vehicle bridge Interaction written by Lina Ding and published by . This book was released on 2010 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: [Truncated abstract] Many load rating methods have been developed in recent years to evaluate the safety and serviceability of existing bridges. In general, the rating of a bridge is carried out by comparing the factored live load effects of nominated rating vehicles with the available bridge capacity. Therefore, accurate and practical approaches to calculate the live load on bridges resulting from moving vehicles and to estimate the bridge load carrying capacity are essential for bridge load rating. The research described in this thesis aims to develop a load rating procedure for accurately estimating the load carrying capacity of existing bridges. It involves three main parts of work. First, to obtain a reliable Finite Element (FE) model of the bridge under the current condition, FE model updating analysis is carried out to refine the bridge model based on the field measured vibration data. Second, detailed static nonlinear Finite Element Analysis (FEA) based on the updated FE model is carried out to determine the bridge load carrying capacity. In this part, the dynamic vehicle-bridge interaction is only approximately modelled by using the code specified Dynamic Amplification Factor (DAF) or Dynamic Load Coefficient (DLC). In the third part, to more precisely model dynamic vehicle-bridge interaction and predict the DAF, nonlinear stochastic dynamic response analysis of an equivalent hysteretic Single Degree of Freedom (SDOF) system subjected to a non-stationary non-zero mean excitation are carried out. The equivalent SDOF system is derived from the actual bridge conditions. The advantages of these approaches are that they can model the actual current condition of a bridge by applying the model updating method and take into account the effects of road surface roughness, single or multiple vehicles-bridge interaction and material nonlinearity of prestressed or reinforced concrete. ... At last, based on the principle of equivalent dissipated energy, the resulting load-displacement relationship may be simplified as a bilinear hysteretic model which defines the stiffness of the equivalent SDOF system. The excitation force of the equivalent SDOF system is a non-stationary stochastic process with non-zero mean, which is caused by the vehicle weight and vehicle-bridge interaction. This thesis presents a novel approach to the evolutionary spectral analysis for the random response of a coupled vehicle-bridge system. The proposed method is capable of taking into account the random characteristics of vehicle-bridge interaction induced by road surface roughness and effect of multiple vehicles-bridge interaction. In addition, this method allows each vehicle to be modelled using a mass-spring-damper system with 4 Degrees Of Freedom (DOF). The resulting stochastic dynamic interaction force can be transformed to an excitation force of the equivalent SDOF system by applying the principle of virtual work. Once the mass, damping, stiffness and excitation force of the equivalent SDOF system are determined, the equation of motion of this SDOF system can be solved using the equivalent linearization method. The entire proposed rating procedure is applied to rating of a practical bridge located in the Shire of Roebourne in Western Australia. Also, parametric studies are conducted in this research to investigate the effects of the length ratio, vehicle to bridge frequency ratio, bridge damping ratio, vehicle to bridge mass ratio, vehicle speed, vehicle number and road surface condition on the DAF and DLC.

Download or read book Load Testing of Bridges Two Volume Set written by Eva Lantsoght and published by CRC Press. This book was released on 2022-07-30 with total page 774 pages. Available in PDF, EPUB and Kindle. Book excerpt: Load Testing of Bridges, featuring contributions from almost fifty authors from around the world across two interrelated volumes, deals with the practical aspects, the scientific developments, and the international views on the topic of load testing of bridges. Volume 12, Load Testing of Bridges: Current practice and Diagnostic Load Testing, starts with a background to bridge load testing, including the historical perspectives and evolutions, and the current codes and guidelines that are governing in countries around the world. The second part of the book deals with preparation, execution, and post-processing of load tests on bridges. The third part focuses on diagnostic load testing of bridges. Volume 13, Load Testing of Bridges: Proof Load Testing and the Future of Load Testing, focuses first on proof load testing of bridges. It discusses the specific aspects of proof load testing during the preparation, execution, and post-processing of such a test (Part 1). The second part covers the testing of buildings. The third part discusses novel ideas regarding measurement techniques used for load testing. Methods using non-contact sensors, such as photography- and video-based measurement techniques are discussed. The fourth part discusses load testing in the framework of reliability-based decision-making and in the framework of a bridge management program. The final part of the book summarizes the knowledge presented across the two volumes, as well as the remaining open questions for research, and provides practical recommendations for engineers carrying out load tests. This work will be of interest to researchers and academics in the field of civil/structural engineering, practicing engineers and road authorities worldwide.

Download or read book Adaptive Reliability Analysis of Reinforced Concrete Bridges Using Nondestructive Testing written by Qindan Huang and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There has been increasing interest in evaluating the performance of existing reinforced concrete (RC) bridges just after natural disasters or man-made events especially when the defects are invisible, or in quantifying the improvement after rehabilitations. In order to obtain an accurate assessment of the reliability of a RC bridge, it is critical to incorporate information about its current structural properties, which reflects the possible aging and deterioration. This dissertation proposes to develop an adaptive reliability analysis of RC bridges incorporating the damage detection information obtained from nondestructive testing (NDT). In this study, seismic fragility is used to describe the reliability of a structure withstanding future seismic demand. It is defined as the conditional probability that a seismic demand quantity attains or exceeds a specified capacity level for given values of earthquake intensity. The dissertation first develops a probabilistic capacity model for RC columns and the capacity model can be used when the flexural stiffness decays nonuniformly over a column height. Then, a general methodology to construct probabilistic seismic demand models for RC highway bridges with one single-column bent is presented. Next, a combination of global and local NDT methods is proposed to identify in-place structural properties. The global NDT uses the dynamic responses of a structure to assess its global/equivalent structural properties and detect potential damage locations. The local NDT uses local measurements to identify the local characteristics of the structure. Measurement and modeling errors are considered in the application of the NDT methods and the analysis of the NDT data. Then, the information obtained from NDT is used in the probabilistic capacity and demand models to estimate the seismic fragility of the bridge. As an illustration, the proposed probabilistic framework is applied to a reinforced concrete bridge with a one-column bent. The result of the illustration shows that the proposed framework can successfully provide the up-to-date structural properties and accurate fragility estimates.

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1971 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Study of Improved Methods of In field Capacity Assessment of Reinforced Concrete Bridges written by Matthew B. Gries and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridges, particularly short-span highway bridges, are basic elements of nearly all contemporary transportation networks. For reinforced concrete structures, complete information regarding the number, size, and orientation of steel reinforcement is necessary in order to make a complete strength assessment. Since reinforcement is not visible externally, making an accurate assessment without design drawings is extremely difficult. Improving the accuracy of capacity assessments of reinforced concrete bridges when information regarding the design and construction of the bridge is limited or not available would be useful in a number of situations, including military operations and disaster response. The objective of this project is to develop more reliable means of in-field capacity assessment of reinforced concrete bridges by making improved estimates of the level of longitudinal and shear reinforcement. The proposed assessment procedure is based on comparing measured structural response under controlled loading conditions to predicted structural response from analysis. This report presents results from a preliminary sensitivity study of the analytically predicted response of simply supported reinforced concrete T-beam girders with varying levels of longitudinal and shear reinforcement.

Download or read book Publications of the National Institute of Standards and Technology Catalog written by National Institute of Standards and Technology (U.S.) and published by . This book was released on 1993 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Response Characteristics of Reinforced Concrete Structures written by Sigmund A. Freeman and published by . This book was released on 1976 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bituminous Mixtures and Pavements VI written by A. Nikolaides and published by CRC Press. This book was released on 2015-07-28 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bituminous Mixtures and Pavements contains 113 accepted papers from the 6th International ConferenceBituminous Mixtures and Pavements (6th ICONFBMP, Thessaloniki, Greece, 10-12 June 2015). The 6th ICONFBMP is organized every four years by the Highway Engineering Laboratory of the Aristotle University of Thessaloniki, Greece, in conjunction with

Download or read book Strengthening Techniques for Reinforced Concrete Bridge Superstructures written by Frieder Seible and published by . This book was released on 1990 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1983 with total page 1368 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Modelling of Discrete Materials in Geotechnical Engineering Civil Engineering and Earth Sciences written by Heinz Konietzky and published by CRC Press. This book was released on 2004-10-15 with total page 1022 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this fully up-to-date volume, important new developments and applications of discrete element modelling are highlighted and brought together for presentation at the First International UDEC/3DEC Symposium. Papers covered the following key areas: * behaviour of masonry structures (walls, bridges, towers, columns) * stability and deformation of tunnels and caverns in fractured rock masses * geomechanical modelling for mining and waste repositories * rock reinforcement design (anchors, shotcrete, bolts) * mechanical and hydro-mechanical behaviour of dams and foundations * rock slope stability, deformation and failure mechanisms * modelling of fundamental rock mechanical problems * modelling of geological processes * constitutive laws for fractured rock masses and masonry structures * dynamic behaviour of discrete structures. Numerical Modelling of Discrete Materials in Geotechnical Engineering, Civil Engineering, and Earth Sciences provides an ultra-modern, in-depth analysis of discrete element modelling in a range of different fields, thus proving valuable reading for civil, mining, and geotechnical engineers, as well as other interested professionals.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2005 with total page 842 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the 1st Conference of the European Association on Quality Control of Bridges and Structures written by Carlo Pellegrino and published by Springer Nature. This book was released on 2021-12-11 with total page 1454 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers the latest advances and innovations in the field of quality control and improvement of bridges and structures, as presented by international researchers and engineers at the 1st Conference of the European Association on Quality Control of Bridges and Structures (EUROSTRUCT 2021), held in Padua, Italy on August 29 – September 1, 2021. Contributions include a wide range of topics such as testing and advanced diagnostic techniques for damage detection; SHM and AI, IoT and machine learning for data analysis of bridges and structures; fiberoptics and smart sensors for long-term SHM; structural reliability, risk, robustness, redundancy and resilience for bridges; corrosion models, fatigue analysis and impact of hazards on infrastructure components; bridge and asset management systems, and decision-making models; Life-Cycle Analysis, retrofit and service-life extension, risk management protocols; quality control plans, sustainability and green materials.