In the Pilbara region of WA, Bridge #1056 spans the De Grey River along the Great Northern Highway.

BG&E was engaged to investigate the condition of the steel pile casings associated with the piers for Bridge #1056, including corrosion and section loss of the steel pile casings below, at and above the ground level.

The condition assessment of Bridge #1056 was completed in 2022, reporting varying amounts of corrosion in the pile casings with the greatest amount of section loss (up to 3.5 millimetres for a 12 millimetre thick pile casing) recorded at ground level. The report also confirmed complete loss of coating with no protection to the steel in the zones between the high-water and below ground level.

The project scope included

• Preliminary works.
• Site investigation, including:
  • Visual assessment to determine the condition of the casings and corrosion.
  • Non-destructive testing, including ultrasonic thickness testing of the steel, ferrous dry film thickness gauge to determine coating thickness, coating adhesion testing using AS 3894.9, Method A, and completion of a hammer tap survey.
• Analysis of all site investigations and provision of a written report.