Title:
Preventive Bridge Maintenance – Is the Annual Spring Cleaning Operation Efficient?
Author(s):
Johan Silfwerbrand
Publication:
Web Session
Volume:
ws_S24_JohanSilfwerbrand.pdf
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
3/24/2024
Abstract:
Sustainability is one of the most important issues in the construction business today. An important way to improve the sustainability is to prolong the service life of existing buildings, bridges and other structures. Besides repair and strengthening, preventive maintenance is a measure to prolong the service life. The aim of preventive maintenance is to both protect the structural members from damaging factors and reduce the speed of the deterioration mechanisms. Preventive maintenance of bridges covers measures such as hydrophobic impregnation, removing weed, maintaining the drainage system open, crack repair, mending the railing, and an annual cleaning of the bridge, which is especially important in areas where de-icing salt is used during the winter season. De-icing salt contains chloride ions that when reaching the reinforcement will start the corrosion process. In a Swedish research project, the effect of the annual cleaning on the chloride ingress in concrete has been carried out at the Royal Institute of Technology (KTH). The project contains both laboratory tests and field tests. The field tests were conducted on a bridge in a southern Stockholm suburban. On the railing, a large number of concrete specimens were placed. At the annual cleaning of the bridge in late spring or early summer, half of the specimens was exposed to the high-pressure cleaning water while the other half was “protected” from water cleaning. In the laboratory, the different seasons of the year were mirrored in an accelerated process making four seasons during 28 days. The test results are less significant than anticipated. Cleaning seems to have a beneficial effect but we need to follow the field tests during several more years to strengthen the hypothesis that bridge cleaning is equally important for the bridge’s durability as teeth brushing for your teeth.