Bridge Live Load Models from Weigh-in-motion Data PDF Download

Author: Robert J. Heywood
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages :

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Author: Bala Sivakumar
Publisher: Transportation Research Board
ISBN: 0309155479
Category : Technology & Engineering
Languages : en
Pages : 125

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TRB's National Cooperative Highway Research Program (NCHRP) Report 683: Protocols for Collecting and Using Traffic Data in Bridge Design explores a set of protocols and methodologies for using available recent truck traffic data to develop and calibrate vehicular loads for superstructure design, fatigue design, deck design, and design for overload permits. The protocols are geared to address the collection, processing, and use of national weigh-in-motion (WIM) data. The report also gives practical examples of implementing these protocols with recent national WIM data drawn from states/sites around the country with different traffic exposures, load spectra, and truck configurations. The material in this report will be of immediate interest to bridge engineers. This report replaces NCHRP Web-Only Document 135: Protocols for Collecting and Using Traffic Data in Bridge Design. Appendices A through F for NCHRP Report 683 are available only online.

Author:
Publisher:
ISBN: 9780921303145
Category :
Languages : en
Pages : 12

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The live load model is an important part of the bridge code development process. The paper deals with bridge live loads. Code provisions in the United States, Canada including Ontario, Germany, Australia and Japan are considered; the design loads vary as regards to truck configurations and weights. Current research is also summarized. Information on bridge live loads is taken from weigh-in-motion (WIM), truck surveys, and citation files. The available data serves as a basis for the prediction of extreme loads. Live load models were considered by Ghosn and Moses, Heywood and Nowak, Bez, Cantieni and Jacquemond, and Nowak and Hong. Ghosn and Moses based their study on WIM data; their model includes the variation in the truck weight, multiple presence, dynamic load, and future growth. Heywood and Nowak extrapolated the results of traffic measurements performed in Australia. Bez and Hirt developed a probabilistic live load model using Swiss Traffic data. A live load model recently developed by Nowak and Hong is based on Ontario truck survey data. Extreme 50 year values of moments and shears are derived for a wide range of girder bridges. The load effects are considered for single lanes and multiple-lanes. For the covering abstract of the Conference see IRRD Abstract No. 807839.

Author: Colin O'Connor
Publisher: CRC Press
ISBN: 0203185927
Category : Technology & Engineering
Languages : en
Pages : 359

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This book provides a detailed summary of bridge loads from an international perspective. The authors cover all aspects from the methodology behind the calculation of bridge loads and the complex interactions between loads and bridges, to economic considerations. A wide range of bridge loads are covered, including highway vehicle loads, pedestrian l

Author: Airong Chen
Publisher: Routledge
ISBN: 1351208772
Category : Technology & Engineering
Languages : en
Pages : 275

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Bridges play important role in modern infrastructural system. This book provides an up-to-date overview of the field of bridge engineering, as well as the recent significant contributions to the process of making rational decisions in bridge design, assessment and monitoring and resources optimization deployment for the purpose of enhancing the welfare of society. Tang specifies the purposes and requirements of the conceptual bridge design, considering bridge types, basic elements, structural systems and load conditions. Cremona and Poulin propose an assessment procedure for existing bridges. Kallias et al. develop a framework for the performance assessment of metallic bridges under atmospheric exposure by integrating coating deterioration and corrosion modelling. Soriano et al. employ a simplified approach to estimate the maximum traffic load effect on a highway bridge and compare the results with other approaches based on on-site weigh-in-motion data. Akiyama et al. propose a method for reliability-based durability design and service life assessment of reinforced concrete deck slab of jetty structures. Chen et al. propose a meso-scale model to simulate the uniform and pitting corrosion of rebar in concrete and to obtain the crack patterns of the concrete with different rebar arrangements. Ruan et al. present a traffic load model for long span multi-pylon cable- stayed bridges. Khuc and Catbas implement a non-target vision- based method for the measurement of both static and dynamic displacements time histories. Finally, Cruz presents the career of the outstanding bridge engineer Edgar Cardoso in the fields of bridge design and experimental analysis. The book serves as a valuable reference to all concerned with bridge structure and infrastructure systems, including students, researchers, engineers, consultants and contractors from all areas sections of bridge engineering. The chapters originally published as a special issue in Structure and Infrastructure Engineering.

Author:
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 333

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New load design factors and models are introduced to account for site-specific live-load demands in the state of New Jersey. Live-load for highway bridges is highly site specific. The current AASHTO LRFD design specifications provide a notional design truck to which load factors are applied. These strength design factors were calibrated using reliability theory to provide a consistent level of safety for various spans and bridge types. The original calibration was done using a small sample of data from decades ago. Truck weights and volumes have significantly increased, reducing the level of safety of highway bridges designed today. Live-load is quantified using an extensive weigh-in-motion (WIM) database for the state of New Jersey as well as instrumentation at a bridge located in the heart of Port Newark, NJ. An integrated system combines a WIM system to measure truck loads and a data logger to capture the strains and deflections. This, first of its kind, system provides a complete picture of bridge behavior. The WIM data collected include all of the parameters needed to quantify truck loading: gross and axle weights, axle spacings, classification, counts, speeds, lane, etc. The bridge response includes parameters such as: strains and deflections. Information on truck loads are used to develop load effect envelopes for various span lengths. The load effects are then extrapolated using Normal probability paper to predict the maximum expected levels for the full service life of 75 years. The effect of other distributions, various measurement durations, and truck multiple presence is also studied. Based on the analysis of moment and shear envelops for various spans, it was found that the current load factors must be increased to maintain the level of safety that the code dictates. A new load model is proposed to provide a more uniform bias for New Jersey trucks. Fatigue load effects are studied in terms of effective truck weights, truck dimensions, and multiple presence in comparison with current evaluation procedures. Experimental load and response data from the instrumented bridge along with computer models is used to study the effect of truck weight, volume, and multiple presence of the fatigue life. Statistical techniques developed by the automotive industry are applied to short experimental measurements to predict a fatigue load profile that would be expected if measurement extended to a much longer duration. The rainflow extrapolation techniques utilize Extreme Value Theory and non-parametric smoothing methods to render a future prediction of the rainflow counted stress cycle matrix. The effect of measurement duration, seasonality, and truck multiple presence on fatigue life prediction is studied.

Author: Zehua Chen
Publisher: CRC Press
ISBN: 0415669863
Category : Mathematics
Languages : en
Pages : 944

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While numerous advanced statistical approaches have recently been developed for quantitative trait loci (QTL) mapping, the methods are scattered throughout the literature. Statistical Methods for QTL Mapping brings together many recent statistical techniques that address the data complexity of QTL mapping. After introducing basic genetics topics and statistical principles, the author discusses the principles of quantitative genetics, general statistical issues of QTL mapping, commonly used one-dimensional QTL mapping approaches, and multiple interval mapping methods. He then explains how to use a feature selection approach to tackle a QTL mapping problem with dense markers. The book also provides comprehensive coverage of Bayesian models and MCMC algorithms and describes methods for multi-trait QTL mapping and eQTL mapping, including meta-trait methods and multivariate sequential procedures. This book emphasizes the modern statistical methodology for QTL mapping as well as the statistical issues that arise during this process. It gives the necessary biological background for statisticians without training in genetics and, likewise, covers statistical thinking and principles for geneticists. Written primarily for geneticists and statisticians specializing in QTL mapping, the book can also be used as a supplement in graduate courses or for self-study by PhD students working on QTL mapping projects.

Author: Michel Ghosn
Publisher: Transportation Research Board
ISBN: 0309087503
Category : Bridges
Languages : en
Pages : 183

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Chapter 1. Introduction -- Chapter 2. Reliability models for combinations of extreme events -- Chapter 3. Calibration of load factors for combinations of extreme events -- Chapter 4. Conclusions and future research -- References -- Glossary of notations -- Appendixes.

Author: Alessio Pipinato
Publisher: Elsevier
ISBN: 0323860141
Category : Technology & Engineering
Languages : en
Pages : 1048

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Book Description
Innovative Bridge Design Handbook: Construction, Rehabilitation, and Maintenance, Second Edition, brings together the essentials of bridge engineering across design, assessment, research and construction. Written by an international group of experts, each chapter is divided into two parts: the first covers design issues, while the second presents current research into the innovative design approaches used across the world. This new edition includes new topics such as foot bridges, new materials in bridge engineering and soil-foundation structure interaction. All chapters have been updated to include the latest concepts in design, construction, and maintenance to reduce project cost, increase structural safety, and maximize durability. Code and standard references have been updated. - Completely revised and updated with the latest in bridge engineering and design - Provides detailed design procedures for specific bridges with solved examples - Presents structural analysis including numerical methods (FEM), dynamics, risk and reliability, and innovative structural typologies

Author: Eugene OBrien
Publisher: CRC Press
ISBN: 1000459918
Category : Technology & Engineering
Languages : en
Pages : 236

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Book Description
There is considerable uncertainty about what level of traffic loading bridges should be designed for. Codes specify notional load models, generally to represent extreme levels of normal traffic, but these are often crude and have inconsistent levels of safety for different load effects. Over the past few decades, increasing quantities of reliable truck weight data has become available and it is now possible to calculate appropriate levels of bridge traffic loading, both for specific bridges and for a road network. Bridge Traffic Loading brings together experts from all over the world to deliver not just the state-of-the-art of vertical loading, but also to provide recommendations of best-practice for all the major challenges in the field – short-span, single and multi-lane bridge loading, dynamic allowance and long-span bridges. It reviews issues that continue to be debated, such as which statistical distribution is most appropriate, whether free-flowing or congested traffic governs and dealing with future traffic growth. Specialist consultants and bridge owners should find this invaluable, as will regulators.