Evaluating the Impact of Bridge Deck Removal Method on the Performance of Precast/Prestressed Concrete I-Girders

Authors

Shaddi Assad, University of Nebraska-LincolnFollow

Date of this Version

8-2014

Citation

Assad, Shaddi A. "Evaluating the Impact of Bridge Deck Removal Methods on the Performance of I-Girders." Thesis. University of Nebraska at Lincoln, 2014. Print.

Comments

A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Construction, Under the Supervision of Professor George Morcous. Lincoln, Nebraska: August, 2014

Copyright (c) 2014 Shaddi A. Assad

Abstract

Wide flange precast/prestressed concrete I-girders have been widely used by several State Departments of Transportation (DOTs) in the last two decades. These girders have many advantages over standard AASHTO I-girders. Their wide and thick bottom flange accommodates a large number of prestressing strands and their wide and thin top flange provides a shorter deck span, reduced girder weight, greater stability in construction, and adequate platform for workers. Despite these advantages, the wide and thin top flange might be disadvantageous when it comes to deck removal, as it is more susceptible to damage. Therefore there is a need to investigate the impact of deck removal methods on the performance of the supporting wide flange I-girder.

In this thesis, two deck removal methods are presented: saw cutting and jack hammering. The two methods were implemented on the Camp Creek Bridge over I-80 in Lancaster County, NE before demolition due to its functional obsolesces. Different saw cutting and jack hammering techniques were performed for deck removal between girders and on top of girders. Data obtained from using similar techniques on three other projects were collected and analyzed. Two girders from the Camp Creek Bridge were taken to the lab for testing in flexure after applying different levels of deck removals around shear connectors and re-decking. Test results indicated adequate performance of the new composite section even when partial deck removal around shear connectors is applied.

Another investigation was conducted to evaluate the effect of top flange width on the performance of bridge I-girders. Top flange was assumed to be longitudinally saw cut and its width is reduced by fifty percent. The effects on geometrical properties, flexural capacity, horizontal shear capacity, and deflection were investigated analytically and experimentally under construction loads and service loads. Investigation results indicate that in some cases top flange width does not have significant impact on the structural performance of I-girders.

Adviser: George Morcous