Validating Non-Destructive Evaluation Technology for Timber Pole Asset Management: Phase 2

Project Overview Ausgrid is one of Australia's largest electricity distribution network operators, responsible for maintaining more than 440,000 timber utility poles across New South Wales. Ausgrid sought to rigorously evaluate whether modern non-destructive evaluation (NDE) technology could reliably replace or supplement their established Sound, Dig and Drill (SDD) inspection practices, the primary question being, “can we reduce or eliminate the need for digging and drilling poles”. The Thor PoleTest device had shown promise in Phase 1 field trials, but a robust, independent validation against real-world destructive testing outcomes was required before any changes to inspection protocols could be justified.

Based on over 15 years of specialist timber pole assessment and destructive testing experience, CoEng designed and executed a comprehensive testing and analysis program. This included field inspections, targeted pole selection, destructive testing, measurement system analysis, and remedial treatment e

valuation. The scope was structured across multiple separable portions, addressing both the structural integrity validation of the Thor device and the broader question of what to do with existing below ground pole treatment practices.

A key component of the engagement also involved evaluating Ausgrid's existing below ground pole bandage treatment program. CoEng coordinated an industry-wide survey, life table analysis, and a detailed review of available remedial treatment products to provide Ausgrid with the evidence base needed to make informed decisions about the continuation and optimisation of their external pole treatment strategy.

Key Activities:

NDE Technology Validation and Field Inspection Program: Detailed field assessments and identifying candidate poles for destructive testing based on condition indices and structural ratings.

Destructive Testing of Ex-Service Poles: CoEng tested more than 50 ex-service poles, including detailed cross-section analysis at the failure location.

Measurement System Analysis for Repeatability and Reproducibility: Compared NDE results across multiple inspectors and thousands of Thor tests to quantify measurement system variation and evaluate the device's suitability for network-wide deployment.

Comparative Assessment of NDE and SDD: Comparison of Thor NDE outcomes against visual grading assessments and SDD inspection results, analysing accuracy, failure type classification, and serviceability ratings to develop calibration recommendations and refined inspection criteria.

Below-Ground Remedial Treatment Review: Industry survey of Australian utility practices, life table analysis of performance data compared to the same in an adjacent network which doesn’t use bandages, and a comprehensive review of available bandage products to evaluate the ongoing value of Ausgrid's external pole treatment program.

Technical Reporting and Stakeholder Engagement: CoEng prepared detailed assessment reports, data frameworks, and recommendations for each separable portion of the project, presenting findings to Ausgrid stakeholders and providing a clear pathway for the implementation of Thor and refining pole inspection and maintenance protocols.

Over the course of nearly a year, CoEng provided rigorous inspection, destructive testing, statistical measurement system analysis, comparative field data, and rigorous recommendations. CoEng has equipped Ausgrid with the technical foundation to make confident, data driven decisions about the future of their pole inspection program.