Details:

Creators:
Brandt, Thomas ; Varma, Amit ; Rankin, Brent ; Marcu, Sorin ; Connor, Robert ; ... More +
Brandt, Thomas ; Varma, Amit ; Rankin, Brent ; Marcu, Sorin ; Connor, Robert ; Harries, Kent Less -
Corporate Creators:
University of Pittsburgh
Corporate Contributors:
Pennsylvania. Dept. of Transportation
Subject/TRT Terms:
[+]
Girders--Effect Of Temperature On Iron Iron And Steel Bridges--Effect Of Temperature On Steel Steel--Fire Testing Steel Bridges Steel By Properties
Publication/ Report Number:
FHWA-PA-2011-005-PIT011
Resource Type:
Tech Report
Geographical Coverage:
Pennsylvania
Edition:
Final report; Nov. 1, 2009-Apr. 30, 2011.
Corporate Publisher:
Pennsylvania. Dept. of Transportation
Abstract:
It is well known that fire can cause severe damage to steel bridges. There are documented cases where fire has directly led to the collapse or significant sagging of a steel bridge. However, when the damage is less severe, the effects of the fire, if any, are not so clear. Evaluation techniques that can be performed easily in the field, but still provide uniform and meaningful information for this situation are lacking. The objective of this research is to develop simple yet effective guidelines for assessing the potential level of damage sustained during a fire when there are no obvious signs of distress (i.e., sagging, collapse). The guidelines are intended to be used by inspectors and engineers in the field immediately following the fire event to provide general insight into the potential influence the fire may have had on the material properties of the bridge steel, based on the visual appearance of the steel.

A unique testing method is reported in which flange and web sections from a bridge girder are tested in real fire scenarios. The test setup allows for the examination of differences in outcomes due to a variety of paint coatings on the steel, thickness of steel, temperature and duration of fire exposure. Each test is photographed at certain stages that would be seen at a fire affected-bridge. These photographs can then be compared to actual bridge damage and an estimate of surface temperature attained. Following each fire test, material properties may be determined and compared to virgin or unexposed steel and AASHTO specifications to establish whether the material properties have changed or if the material is below minimum standards. Since the test setup and procedures are well defined, the test method can be standardized so that additional data can be collected in a consistent manner and incorporated into the guidelines in the future.

This report, and more specifically the inspection guide provided in Chapter 7, provides a much-needed tool for the inspection and evaluation of steel bridge members exposed to fires where obvious physical damage has not occurred. It will allow uniform and quick initial determination on a bridge’s serviceability after undergoing fire exposures.


Format:
PDF
Funding:
510601-PIT 011
Collection(s):
US Transportation Collection
Main Document Checksum:
[+]
urn:sha256:bc29e88184d0cddf8d3b68f5a8e59dc382c421b8e6f66716cce22315374d946a
Download URL:
https://rosap.ntl.bts.gov/view/dot/20403/dot_20403_DS1.pdf
File Type:

Supporting Files

• No Additional Files

More +