Discusses "the safety concepts which form the basis of modern bridge design and assessment codes" and "the background work carried out in the development of the new UK bridge and route-specific traffic loading requirements, and the proposed whole life performance-based assessment rules" -- Preface.

Condition assessment and safety verification of existing bridges and decisions as to whether bridge posting is required are addressed through analysis, load testing, or a combination of methods. Bridge rating through structural analysis is by far the most common procedure for rating existing bridges. The American Association of State Highway and Transportation Officials (AASHTO) Manual for Bridge Evaluation (MBE), First Edition permits bridge capacity ratings to be determined through allowable stress rating (ASR), load factor rating (LFR) or load and resistance factor rating (LRFR); the latter method is keyed to the AASHTO LRFD Bridge Design Specifications, which is reliability-based and has been required for the design of new bridges built with federal findings since October, 2007. A survey of current bridge rating practices in the United States has revealed that these three methods may lead to different ratings and posting limits for the same bridge, a situation that carries serious implications with regard to the safety of the public and the economic well-being of communities that may be affected by bridge postings or closures. To address this issue, a research program has been conducted with the overall objective of providing recommendations for improving the process by which the condition of existing bridge structures is assessed. This research required a coordinated program of load testing and finite element analysis of selected bridges in the State of Georgia to gain perspectives on the behavior of older bridges under various load conditions. Structural system reliability assessments of these bridges were conducted and bridge fragilities were developed for purposes of comparison with component reliability benchmarks for new bridges. A reliability-based bridge rating framework was developed, along with a series of recommended improvements to the current bridge rating methods, which facilitate the incorporation of various in situ conditions of existing bridges into the bridge rating process at both component and system levels. This framework permits bridge ratings to be conducted at three levels of increasing complexity to achieve the performance objectives, expressed in the terms of reliability, that are embedded in the LRFR option of the AASHTO Manual of Bridge Evaluation. This research was sponsored by the Georgia Department of Transportation, and has led to a set of Recommended Guidelines for Condition Assessment and Evaluation of Existing Bridges in Georgia.

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.

With the development in global economic and transportation engineering, the traffic loads on brides have been growing steadily, which become potential safety hazards for existing bridges. In particular, long-span suspension bridges support heavy traffic volumes and simultaneous truck loads on the bridge deck, and thus the safety and serviceability of the bridge deserves investigation. In this book, a multiscale reliability method is presented for the safety assessment of long-span bridges. The multiscale failure condition of stiffness girders is the first-passage criteria for the large-scale model and the fatigue damage criteria for the small-scale model. It is the objective of this book to provide a more in-depth understanding of the vehicle-bridge interaction from the random vibration perspective. This book is suitable for adoption as a text book or a reference book in an advanced structural reliability analysis course. Furthermore, this book also provides a theoretical foundation for better understanding of the safety assessment, operation management, maintenance and reinforcement for long-span bridges and motivates further research and development for more advanced reliability and serviceability assessment techniques for long-span bridges.

Focussing on structural reliability methods, reliability-based optimization, structural system reliability and risk analysis, lifetime performance and various applications in civil engineering. Invaluable to all concerned with structural system reliability and optimization, especially students, engineers, and workers in research and development.