A major part of the repair work being carried out to the Tay Road Bridge involves the cathodic protection of concrete river columns. This paper describes the requirements for, and development of, cathodic protection and an associated monitoring scheme. It outlines the methodology used to assess the suitability of the automated cathodic protection monitoring system. In developing an automated system several complex electrical problems had to be overcome in particular the issue of noise and its effect on the measurements. The system chosen uses titanium expanded mesh anodes coated with mixed metal oxides fixed to the column surface and encapsulated in a 50mm thick cast concrete overlay. This is concrete overlay. This is applied to the bottom 6m of the columns and connected to transformer rectifier power supply units on the central pedestrian walkway.
Abstract