Details:

Creators:
Schanck, Andrew ; Davids, Bill
Schanck, Andrew ; Davids, Bill Less -
Corporate Creators:
University of Maine. Advanced Structures and Composites Center
Corporate Contributors:
Maine. Dept. of Transportation. Transportation Research Division
Subject/TRT Terms:
[+]
Live Loads Load Factor Load Tests Reinforced Concrete Bridges Reinforced Concrete T-beam Bridges Skewed Structures
Publication/ Report Number:
ME 20-01 ; Technical Report 20-01 ; 20-20-1613
ME 20-01 ; Technical Report 20-01 ; 20-20-1613 Less -
Resource Type:
Tech Report
Geographical Coverage:
United States
Edition:
2019-12-20-Rev00
Corporate Publisher:
Maine. Department of Transportation
Abstract:
Maine’s bridge inventory includes a significant number of reinforced concrete T-beam bridges, both with and without skew. Many of these bridges were built in the first half of the 20th century for design loadings much lower than those considered today, causing a significant number of them to have low flexural rating factors. Despite this, these bridges continue to carry modern levels of loading with little to no apparent distress. This observation has resulted in new efforts to better understand the behavior of these bridges and to develop new methods of analysis which more accurately reflect their true capacities. In the summers of 2017 and 2018, ten reinforced concrete T-beam bridges were non-destructively live-load tested to update their rating factors and to observe their load-strain responses. Five bridges were un-skewed and five were skewed between 15° and 35° relative to a perpendicular alignment. This selection of tested bridges allowed their responses to loading to be compared with the aim of identifying differences in behavior arising from the presence of skew. The understanding of these differences was also enhanced through the construction, calibration, and analysis of detailed, linear finite element models of the tested bridges. The ten bridges that had been live-load tested were also load-rated through Proxy finite element analysis (FEA) to give a more accurate picture of their behavior at capacity. Each of these bridges’ flexural rating factors were able to be significantly improved relative to their American Association of State Highway and Transportation Officials (AASHTO) calculated ratings, and nine of the ten were improved relative to their ratings updated through live-load testing. It is demonstrated that these ratings are optimistic, yet also realistic considering the technique’s reliance on well-established mechanics and conservative assumptions. The possible future development of this technique as a general load rating tool for older structures is discussed.
Content Notes:
Note: While the third page of the report is stamped "Confidential," this item is publicly available via the Maine DOT website at https://www.maine.gov/mdot/research/publications/ and was submitted directly to NTL for inclusion in our repository in 2020.
Format:
PDF
Funding:
Project 23833.00
Collection(s):
US Transportation Collection
Main Document Checksum:
[+]
urn:sha256:546b27adb6f3a17a60f93aefc72de9552d74a811a33121fe8db37dbcd5a1eb73
Download URL:
https://rosap.ntl.bts.gov/view/dot/62681/dot_62681_DS1.pdf
File Type:

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