Maintenance and monitoring of anchorages: guidelines

The maintenance and monitoring of permanent anchorages are important, particularly for anchorages installed over 30 years ago that may have been designed with inferior or inadequate corrosion protection. Following a review of tendon corrosion failures and observed anchor head conditions after 28–33 years of service in aggressive environments, guidelines on good practice for inspection, testing, maintenance and service behaviour monitoring are presented. Topics include designer responsibility, outer and inner anchor head inspection, component and material testing, grease assessment, monitoring with load cells, load lift-off checking using multi-unit and mono-unit jacks, on-site cyclic loading acceptance testing, anchor head design to facilitate monitoring, extent and frequency of inspections and service behaviour monitoring, and associated records. Current national, European and international recommendations are also summarised.