Calibration of LRFR Live Load Factors Using Weigh-in-motion Data
Author : Jordan Pelphrey
Publisher :
Page : 137 pages
File Size : 16,73 MB
Release : 2006
Category : Bridges
ISBN :
Illinois-specific Live-load Factors Based on Truck Data
Author : Gongkang Fu
Publisher :
Page : 349 pages
File Size : 28,81 MB
Release : 2019
Category : Bridges
ISBN :
Book Description
This research project has a focus on the load and resistance factored rating (LRFR) live-load factors for load rating bridges in Illinois. The study’s objectives were to examine the adequacy of available Illinois weigh-in-motion (WIM) data and to develop refined live-load factors for Illinois LRFR practice, based on recorded truck loads in Illinois. There are currently 20 operating WIM sites in Illinois, each next to a weigh station. Initially, only one WIM site was providing two lanes of truck-weight data simultaneously recorded, while the remaining 19 were collecting data for the driving lane only. Twolane WIM data are important for live-load factor refinement because it is the cluster events involving trucks in different lanes that induce maximum load effects in primary bridge components such as girders. Thus, such data are critical to live-load factors. Upon recommendation from this project, the capability of passing-lane recording was promptly added to two more of the 20 sites. An additional effort was made in this study to simulate the passing lane’s data for the remaining 17 sites, to maximize the use of Illinois-relevant WIM data for covering the entire state. This simulation used the probability of multiple trucks in a cluster, based on WIM data from eight states including Illinois. It also used truck-weight-demography information and headway distances of trucks in cluster from all available Illinois sites. This simulation method was tested and proven in the present project to be reliable for calibration here for Illinois. The resulting truck records of these 17 sites and those recorded at the other 3 sites capable of providing two lanes of truckweight data from 2013 to 2017 were then used to develop refined live-load factors for LRFR in Illinois. Illinois trucks are seen in these WIM data to be less severe than those weighed in Canada, which were used in calibrating the current AASHTO LRFD Bridge Design Specifications (BDS) (2017). Illinois trucks recorded in the WIM data were also found to have behaved with little or no influence from the nearby weigh station. Four load-rating cases are addressed in this project in calibrating LRFR live-load factors for Illinois: design load, legal load, routine-permit load, and special-permit load. Based on calibration using Illinois truckweight records, no change for the design load rating is recommended. Lower live-load factors are recommended for the other three cases for Illinois than those prescribed in the current MBE, by about 8% to 14%, depending on average daily truck traffic (ADTT). Illustrative examples using the recommended live-load factors have been prepared and presented in this report. It is also recommended that Illinois Department of Transportation (IDOT) continue to keep the WIM stations well-maintained, including periodical calibration of the weight sensors and systems; gather more truck-weight-data; review them at least biennially; and focus on possible growth of truck load in both magnitude and volume. When funding becomes available, passinglane recording is recommended to be added to those WIM sites that currently do not have this capability. Truck-data gathering is also recommended for sites where congested truck traffic is often observed, given adequate funding for such facilities.
Calibration of Load Factors for LRFR Bridge Evaluation
Author : Fred Moses
Publisher :
Page : 68 pages
File Size : 44,35 MB
Release : 2001
Category : Technology & Engineering
ISBN :
Book Description
Applications of Statistics and Probability in Civil Engineering
Author : Michael Faber
Publisher : CRC Press
Page : 938 pages
File Size : 43,18 MB
Release : 2011-07-15
Category : Technology & Engineering
ISBN : 0203144791
Book Description
Under the pressure of harsh environmental conditions and natural hazards, large parts of the world population are struggling to maintain their livelihoods. Population growth, increasing land utilization and shrinking natural resources have led to an increasing demand of improved efficiency of existing technologies and the development of new ones. A
An Investigation of Oregon Weight-in-motion Data for Bridge Rating Implementation and Evaluation
Author : Jordan Michael Pelphrey
Publisher :
Page : 326 pages
File Size : 33,17 MB
Release : 2006
Category : Bridges
ISBN :
Book Description
The LRFR Manual, within commentary Article C6.4.4.2.3, contains provisions for development of site-specific live load factors. In Oregon, truck Weigh-in-Motion (WIM) data were used to develop live load factors for use on state-owned bridges. The factors were calibrated using the same statistical methods that were used in the original development of LRFR. This procedure maintains the nationally accepted structural reliability index for evaluation, even though the resulting state-specific live load factors were smaller than the national standard. The first part of this report describes the jurisdictional and enforcement characteristics in the state, the modifications used to described the alongside truck population based on the unique truck permitting conditions in the state, the WIM data filtering, sorting, and quality control, as well as the calibration process, and the computed live load factors. Large WIM data sets from four sites were used in the calibration and included different truck volumes, seasonal and directional variations, and WIM data collection windows. Finally, policy implementation for actual use of the factors and future provisions for maintenance of the factors are described. For bridge rating and evaluation, notional truck models are commonly used to simulate the load effects produced by the truck population. The recently developed Load Resistance and Factor Rating (LRFR) Bridge Evaluation Manual was calibrated based on the 3S2 truck configuration as the notional model. Using GVW as the parameter for establishing live load factors to reflect load effects may not necessarily provide consistent outcomes across all bridge span lengths, indeterminacies, or specific load effects. This is because the load effects are dependent on the distributions of the axle weights, the axle spacing, and the number of axles, in addition to the span geometry and support conditions. The Oregon Department of Transportation currently uses a suite of 13 rating vehicles for evaluation of their bridge inventory. The load effects for Oregon's bridge rating vehicles have also been calculated for various span lengths and support conditions in the second part of this report. These load effects, both unfactored and factored, were compared with load effects calculated using vehicles from large sets of WIM data. Further, because no established standard of time or quantity of WIM data has previously been recognized, a separate study was conducted in order to determine an acceptable window of WIM data. The objective of this analysis was to determine if the load effects and the live load factors developed for bridge rating produced by the suite of vehicles envelope load effects produced by an acceptable window of collected vehicle data for a variety of bridge span lengths and types. Observations and suggestions are made based on the results of these analyses.
Protocols for Collecting and Using Traffic Data in Bridge Design
Author : Bala Sivakumar
Publisher : Transportation Research Board
Page : 125 pages
File Size : 43,81 MB
Release : 2011
Category : Technology & Engineering
ISBN : 0309155479
Book Description
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.
Bridge Maintenance, Safety, Management, Life-Cycle Sustainability and Innovations
Author : Hiroshi Yokota
Publisher : CRC Press
Page : 8732 pages
File Size : 32,85 MB
Release : 2021-04-20
Category : Technology & Engineering
ISBN : 100017381X
Book Description
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.
Bridge Design, Assessment and Monitoring
Author : Airong Chen
Publisher : Routledge
Page : 124 pages
File Size : 44,9 MB
Release : 2018-12-07
Category : Technology & Engineering
ISBN : 1351208780
Book Description
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.
Public Roads
Author :
Publisher :
Page : 456 pages
File Size : 24,75 MB
Release : 2005
Category : Highway research
ISBN :
Book Description
Hydro-Environmental Analysis
Author : James L. Martin
Publisher : CRC Press
Page : 5742 pages
File Size : 13,94 MB
Release : 2013-12-04
Category : Science
ISBN : 1138000868
Book Description
Focusing on fundamental principles, Hydro-Environmental Analysis: Freshwater Environments presents in-depth information about freshwater environments and how they are influenced by regulation. It provides a holistic approach, exploring the factors that impact water quality and quantity, and the regulations, policy and management methods that are necessary to maintain this vital resource. It offers a historical viewpoint as well as an overview and foundation of the physical, chemical, and biological characteristics affecting the management of freshwater environments. The book concentrates on broad and general concepts, providing an interdisciplinary foundation. The author covers the methods of measurement and classification; chemical, physical, and biological characteristics; indicators of ecological health; and management and restoration. He also considers common indicators of environmental health; characteristics and operations of regulatory control structures; applicable laws and regulations; and restoration methods. The text delves into rivers and streams in the first half and lakes and reservoirs in the second half. Each section centers on the characteristics of those systems and methods of classification, and then moves on to discuss the physical, chemical, and biological characteristics of each. In the section on lakes and reservoirs, it examines the characteristics and operations of regulatory structures, and presents the methods commonly used to assess the environmental health or integrity of these water bodies. It also introduces considerations for restoration, and presents two unique aquatic environments: wetlands and reservoir tailwaters. Written from an engineering perspective, the book is an ideal introduction to the aquatic and limnological sciences for students of environmental science, as well as students of environmental engineering. It also serves as a reference for engineers and scientists involved in the management, regulation, or restoration of freshwater environments.
