CRASHWORTHY RAILING FOR TIMBER BRIDGES

Bridge railing systems in the United States have historically beers designed based on static load criteria given in the American Association of State Highway and Transportation 0fficials (AASHTO) Standard Specifications for Highway Bridges. In the past decade, full-scale vehicle crash testing has been recognized as a more appropriate and reliable method of evaluating bridge railing acceptability. In 1993, the National Cooperative Highway Research Program published Report 350, Recommended Procedures for the Saftey Performance Evaluation of Highway Features, which provides new criteria for evaluating longitudinal barriers. Based on these specifications, a cooperative research program is continuing between the USDA Forest Service, Forest Products Laboratory, the Midwest Roadside Saftety Facility of the University of Nebraska- Lincoln; and the Federal Highway Administration to develop and crash test bridge railings for wood bridge decks. This paper describes research that resulted in the successful development and testing of several bridge railings for longitudinal and transverse wood decks in accordance with NCHRP Report 350 requirements

CRASHWORTHY RAILING FOR TIMBER BRIDGES

Bridge railing systems in the United States have historically beers designed based on static load criteria given in the American Association of State Highway and Transportation 0fficials (AASHTO) Standard Specifications for Highway Bridges. In the past decade, full-scale vehicle crash testing has been recognized as a more appropriate and reliable method of evaluating bridge railing acceptability. In 1993, the National Cooperative Highway Research Program published Report 350, Recommended Procedures for the Saftey Performance Evaluation of Highway Features, which provides new criteria for evaluating longitudinal barriers. Based on these specifications, a cooperative research program is continuing between the USDA Forest Service, Forest Products Laboratory, the Midwest Roadside Saftety Facility of the University of Nebraska- Lincoln; and the Federal Highway Administration to develop and crash test bridge railings for wood bridge decks. This paper describes research that resulted in the successful development and testing of several bridge railings for longitudinal and transverse wood decks in accordance with NCHRP Report 350 requirements

Plans for Crash-Tested Bridge Railings for Longitudinal Wood Decks

In the past decade, bridge railing design criteria have moved away from static-load design and have focused on full-scale crash testing as a more appropriate and reliable means of evaluating bridge railings. The five bridge railing plans presented reflect the results of a cooperative research project between the Midwest Roadside Safety Facility, University of Nebraska-Lincoln; the USDA Forest Service, Forest Products Laboraotry; and the Federal Highway Administration. The project objective was to develop and crash test bridge railings and approach railing transitions for longitudinal wood bridge decks. The bridge railings were completed in accordance with AASHTO Performance Levell, Performance Level 2, and NCHRP Report 350 Test Level 4 (TL-4). Approach railings were tested or adapted from previous testing in accordance with NCHRP Report 230. Full drawing sets are provided in customary U.S. and SI units of measure. The testing procedures, results, and drawings have been approved by the Federal Highway Administration Federal-Aid and Design Office for use on Federal-aid highway projects

Plans for Crash-Tested Wood Bridge Railings for Concrete Decks

As part of a continuing cooperative research between the Midwest Roadside Safety Facility (MwRSF); the USDA Forest Service, Forest Products Laboratory (FPL); and the Federal Highway Administration (FHWA), several crashworthy wood bridge railings and approach railing transitions have been adapted for use on concrete bridge decks. These railings meet testing and evaluation criteria outlined in National Cooperative Research Program (NCHRP) Report 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features, and include a glued-laminated timber (glulam) rail, with and without a curb, at Test Level- 2 (TL-2), a glulam rail with curb at TL-4, and a glulam curb rail for low-volume roads at TL-1. In adapting the railings from a wood deck to a concrete deck, the critical consideration was railing attachment to the deck. A comparable connection was obtained by an analysis of maximum loads measured by field instrumentation during crash testing or by equating the ultimate capacity of connections used on the wood deck to those required for a concrete deck. For the convenience of the user, full drawing sets are provided in customary U.S. and S.I. units

Plans for Crash-Tested Wood Bridge Railings for Concrete Decks

As part of a continuing cooperative research between the Midwest Roadside Safety Facility (MwRSF); the USDA Forest Service, Forest Products Laboratory (FPL); and the Federal Highway Administration (FHWA), several crashworthy wood bridge railings and approach railing transitions have been adapted for use on concrete bridge decks. These railings meet testing and evaluation criteria outlined in National Cooperative Research Program (NCHRP) Report 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features, and include a glued-laminated timber (glulam) rail, with and without a curb, at Test Level- 2 (TL-2), a glulam rail with curb at TL-4, and a glulam curb rail for low-volume roads at TL-1. In adapting the railings from a wood deck to a concrete deck, the critical consideration was railing attachment to the deck. A comparable connection was obtained by an analysis of maximum loads measured by field instrumentation during crash testing or by equating the ultimate capacity of connections used on the wood deck to those required for a concrete deck. For the convenience of the user, full drawing sets are provided in customary U.S. and S.I. units

Performance of Transportation Infrastructure During Kumamoto Earthquakes of April 14 and 16, 2016\u2014 A Reconnaissance Report

DTFH61-07-00031This report described a reconnaissance effort to document bridge performance during the Kumamoto earthquakes in Japan in April 2016. More than 180 bridges were damaged by these earthquakes. Of particular interest is the performance of bridges that were relatively new (15\u201320 yr old) or recently retrofitted. Damage sustained was significant and included bearing and shear key failures, distortion and local buckling of the steel superstructures, and foundation movement. Most of the damage could be attributed to extensive slope failures and intense shaking close to the causative fault. Recommendations for improving bridge performance in future earthquakes are given

CRASHWORTHY RAILING FOR TIMBER BRIDGES

Bridge railing systems in the United States have historically beers designed based on static load criteria given in the American Association of State Highway and Transportation 0fficials (AASHTO) Standard Specifications for Highway Bridges. In the past decade, full-scale vehicle crash testing has been recognized as a more appropriate and reliable method of evaluating bridge railing acceptability. In 1993, the National Cooperative Highway Research Program published Report 350, Recommended Procedures for the Saftey Performance Evaluation of Highway Features, which provides new criteria for evaluating longitudinal barriers. Based on these specifications, a cooperative research program is continuing between the USDA Forest Service, Forest Products Laboratory, the Midwest Roadside Saftety Facility of the University of Nebraska- Lincoln; and the Federal Highway Administration to develop and crash test bridge railings for wood bridge decks. This paper describes research that resulted in the successful development and testing of several bridge railings for longitudinal and transverse wood decks in accordance with NCHRP Report 350 requirements

Plans for Crash-Tested Bridge Railings for Longitudinal Wood Decks

In the past decade, bridge railing design criteria have moved away from static-load design and have focused on full-scale crash testing as a more appropriate and reliable means of evaluating bridge railings. The five bridge railing plans presented reflect the results of a cooperative research project between the Midwest Roadside Safety Facility, University of Nebraska-Lincoln; the USDA Forest Service, Forest Products Laboraotry; and the Federal Highway Administration. The project objective was to develop and crash test bridge railings and approach railing transitions for longitudinal wood bridge decks. The bridge railings were completed in accordance with AASHTO Performance Levell, Performance Level 2, and NCHRP Report 350 Test Level 4 (TL-4). Approach railings were tested or adapted from previous testing in accordance with NCHRP Report 230. Full drawing sets are provided in customary U.S. and SI units of measure. The testing procedures, results, and drawings have been approved by the Federal Highway Administration Federal-Aid and Design Office for use on Federal-aid highway projects