01731876

Monograph

http://www.trb.org/Main/Blurbs/180078.aspx

This project seeks to develop a new guide specification on the service life design of highway bridges for adoption by AASHTO, including a set of case studies that demonstrate its application. The goals of the new guide specification were to provide practical guidance to designers of highway bridges on how to implement service life design during the design phase, utilize available data together with bridge owner experience to tie design practices to service life, and to allow for the future incorporation of probabilistically calibrated limit states. Information was gathered from a literature review, a survey of transportation agencies, and members of the research team. The guide specification itself was developed around a three-tiered approach of “good-better-best” practices tied to three categories of service life: normal, enhanced, and maximum. Definitions of exposure classes are included to aid the designer in categorizing the severity of the environment surrounding a bridge. Material and component specific design specifications are provided as a function of service life category and/or exposure class, most of which take the form of deemed-to-satisfy or avoidance of deterioration approaches. The exception to this is the limit state of chloride-induced corrosion of reinforced concrete, for which design concrete cover values were probabilistically calibrated. An appendix provides the background to this probabilistic approach to chloride-induced corrosion, and is intended for use with project specific requirements. This appendix also provides a framework for the future inclusion of additional limit states. The Guide Specification concludes with a set of case studies demonstrating the use of the developed service life design provisions.

NCHRP 12-108

English

292p

2020

NCHRP Web-Only Document

9780309671477

Contractor's Final Report

Digital/other

Appendices; Figures; References; Tables

Bridge design; Highway bridges; Limit state design; Service life; Specifications

Bridges and other structures; Design; Highways

TRIS, TRB, ATRI

Jan 28 2020 3:10PM