Title: The Conservation State of Highway Foundation Bridge Piles

Author(s): Christian Paglia, Albert Jornet

Publication: Symposium Paper

Volume: 355

Issue:

Appears on pages(s): 477-484

Keywords: foundation piles, corrosion, chloride, stray current, galvanostatic measurements

DOI: 10.14359/51736055

Date: 7/1/2022

Abstract:
The conservation state of foundation piles of highway viaducts close to a train line was investigated with a visual inspection, laboratory tests on the cementitious material and electrochemical monitoring, as well as galvanostatic pulse measurements for the steel parts. Each viaduct pile had 10 to 15 foundation piles inserted into the ground to a depth down to 15 meters. Two main types of piles were observed. Reinforced concrete piles and steel piles were embedded internally and externally in the cementitious material. The results indicated the absence of significant corrosion of the metals in the upper part of the piles. This was also due to poor carbonation in the ground. Along a viaduct, the presence of chloride in the groundwater increased the risk of corrosion, although it did not reach the steel parts yet. The monitoring of the stray currents did not exhibit a relevant shift in the anodic direction of the steel corrosion potential, thus indicating a reduced corrosion risk. The galvanostatic pulse measurements showed some possible local corrosion issues that may arise, especially with depth. This also depended on the formation of macroelements along the piles. Nevertheless, this latter problem may be reduced due to the higher presence of humidity and the oxygen depletion with depth.