Techno Press
You logged in as Techno Press

Structural Engineering and Mechanics
  Volume 82, Number 1, April10 2022 , pages 69-79

Field distribution factors and dynamic load allowance for simply supported double-tee girder bridges
Brian Kidd, Sandip Rimal, Junwon Seo, Mostafa Tazarv and Nadim Wehbe

    This paper discusses the field testing of two single-span double-tee girder (DTG) bridges in South Dakota to determine live load distribution factors (LLDFs) and the dynamic load allowance (IM). One bridge had seven girders and another had eight girders. The longitudinal girder-to-girder joints of both bridges were deteriorated in a way that water could penetrate and the joint steel members were corroded. A truck traveled across each of the two bridges at five transverse paths. The paths were tested twice with a crawl speed load test and twice with a dynamic load. The LLDFs and IM were determined using strain data measured during the field tests. These results were compared with those determined according to the AASHTO Standard and the AASHTO LRFD specifications. Nearly all the measured LLDFs were below the AASHTO LRFD design LLDFs, with the exception of two instances: 1) An exterior DTG on the seven-girder bridge and 2) An interior DTG on the eight-girder bridge. The LLDFs specified in the AASHTO Standard were conservative compared with the measured LLDFs. It was also found that both AASHTO LRFD and AASHTO Standard specifications were conservative when estimating IM, compared to the field test results for both bridges.
Key Words
    double-tee girder bridges; dynamic load allowance; field testing; live load distribution factor; longitudinal joint damage
Brian Kidd, Sandip Rimal, Junwon Seo, Mostafa Tazarv and Nadim Wehbe: Department of Civil and Environmental Engineering, South Dakota State University, Brookings, SD 57007, USA

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2023 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: