As part of an integrity assessment of prestressed ground anchorages installed in a gravity dam, a trial on-site corrosion monitoring investigation was carried out, in which three 122 mm diameter cores, up to 70 m deep were drilled into the dam adjacent to three of the anchorages. A novel probe arrangement was then lowered into the core (which was filled with water) and electrochemical potential, corrosion rate (LPR) and system resistance measurements made at 2 m intervals down the core.

The objective of the trial was to attempt to establish if corrosion of the tendon was active, and if that was the case to provide an estimate of the rate of corrosion of the tendon.

In order to determine the area of anchorage being polarised in the LPR measurement, a finite element analysis model of the system was developed and used in conjunction with the resistance data obtained. The rates were also compared to laboratory test results carried out on actual ground water samples taken from within the dam.

  • Introduction

  • Investigation

  • Results

  • Conclusions

  • References

This content is only available via PDF.
You do not currently have access to this chapter.
Don't already have an account? Register

Purchased this content as a guest? Enter your email address to restore access.

Please enter valid email address.
Email address must be 94 characters or fewer.