TY - GEN
T1 - Avoiding Failures during Assembly of a Trunnion-Hub-Girder for Bascule Bridges
AU - Besterfield, Glen H
AU - Nichani, Sanjeev
AU - Kaw, Autar
AU - Eason, Thomas
AU - Cherukara, Thomas
PY - 2002/1/1
Y1 - 2002/1/1
N2 - This paper is a study of avoiding failures during the assembly of a trunnion-hub-girder (THG) for bascule bridges. The currently used assembly procedure, AP#1, cools the trunnion for a shrink fit into the hub, followed by cooling of the trunnion-hub assembly to shrink fit it into the girder. During assembly, using AP#1, development of cracks on the hub was observed in one THG assembly. Yet, during another assembly, the trunnion got stuck in the hub before it could be fully inserted. A complete analytical, numerical, and experimental study was conducted to understand these failures, and the results were used to develop specifications and recommendations for assembly. The causes of failures include development of high stresses at low temperatures during assembly, while noting that fracture toughness of THG material decreases with temperature. Recommended specifications included following an alternative assembly procedure that doubled allowable crack length, and lower cooling temperatures to avoid trunnions sticking in the hub.
AB - This paper is a study of avoiding failures during the assembly of a trunnion-hub-girder (THG) for bascule bridges. The currently used assembly procedure, AP#1, cools the trunnion for a shrink fit into the hub, followed by cooling of the trunnion-hub assembly to shrink fit it into the girder. During assembly, using AP#1, development of cracks on the hub was observed in one THG assembly. Yet, during another assembly, the trunnion got stuck in the hub before it could be fully inserted. A complete analytical, numerical, and experimental study was conducted to understand these failures, and the results were used to develop specifications and recommendations for assembly. The causes of failures include development of high stresses at low temperatures during assembly, while noting that fracture toughness of THG material decreases with temperature. Recommended specifications included following an alternative assembly procedure that doubled allowable crack length, and lower cooling temperatures to avoid trunnions sticking in the hub.
KW - bascule bridge
KW - bridge design
KW - finite element analysis
KW - nonhomogenous properties
KW - strain measurement
KW - stress analysis
KW - thermal stresses
UR - https://digitalcommons.usf.edu/egr_facpub/178
UR - https://doi.org/10.1115/IMECE2002-39605
U2 - 10.1115/IMECE2002-39605
DO - 10.1115/IMECE2002-39605
M3 - Other contribution
ER -