Article
Rehabilitation of Deteriorated Timber Piles Using FRP Composites
Structural Engineering International
(2017)
Abstract
Louisiana has a large inventory of timber bridges in service. The timber piles in these bridges are succumbing to the effects of biological degradation that initiates in the wet-dry zones. Replacing these deteriorated piles is a costly process and in-situ repair of the piles with fiber reinforced polymers (FRP) is an economic alternative that does not require shoring the superstructure and does not interfere with the daily operation of the bridge. An experimental program was conducted to evaluate the capacity of FRP strengthened deteriorated timber piles under concentric and eccentric loads with different deterioration configurations. A total of 42 monotonic tests were conducted; 21 on concentrically loaded piles and 21 on eccentrically loaded piles. Three commercially available repair techniques were investigated to evaluate the efficiency of the repair with respect to restoring the original capacity of the pile. All repaired techniques were able to restore and typically enhance the original capacity of the undamaged piles. All failure modes were observed in the wooden portion of the pile outside the repaired region. The capacity of the repaired piles may be based on the undamaged timber portion of the pile. A method is presented to predict the axial load versus axial deformation relationship of concentrically loaded repaired piles. Strain gage measurements indicate that the FRP shell is mobilized more when the annular space is smaller due to the lower axial stiffness of the repaired pile compared to cases that feature larger annular spaces. Relative displacements between the repaired and unrepaired portions of the pile suggest that the repaired piles behaved compositely throughout the tests. Also, no sign of slip was observed at the top or bottom of the repair.
Keywords
- bearing capacity,
- cost effectiveness,
- fiber reinforced polymers,
- rehabilitation (maintenance),
- repairing,
- testing,
- wooden bridges
Disciplines
Publication Date
September, 2017
Citation Information
David E Hall, Fatmir Menkulasi, Hadi Baghi and Nahid Farzana. "Rehabilitation of Deteriorated Timber Piles Using FRP Composites" Structural Engineering International (2017) Available at: http://works.bepress.com/david-hall/5/