Introduction
Tarong Energy Corporation (TEC) have engaged Vertigo Specialist High Access Services (Vertigo) in conjunction with Austress Freyssinet / Ian Godson & Associates to perform inspection & testing to the reinforced concrete elements of two 116-meter high natural draft cooling towers serving units 1-2 & 3-4 at Tarong Power Station in south east Queensland.
Site works were conducted during planned unit outages in June & August 2007.
Scope of Work
A temporary rope access system from which to perform the work on the towers was installed initially utilising helicopter lifts.
Visual inspection was conducted to selected portions of the internal & external shell surfaces and selected base structure concrete elements.
Detailed concrete testing that included cover survey, carbonation, half cell potential & resistivity measurements were performed at a number of selected test areas. Laboratory testing was performed on retrieved core samples.
Outcome
Vertigo successfully completed the inspection & investigation within the outage time window. A report was issued reviewing the condition of the structure & the remedial strategy required to extend the design service life of the structure.