World-First Project to 'Self Heal' Cracked Concrete Using Sloppy Sludge Could Save $1.4 Billion Annual Repair Bill to Australia’s Sewer Pipes
A world-first project led by University of South Australia sustainable engineering expert Professor Yan Zhuge is trialling a novel solution to halt unprecedented levels of corrosion in the country’s ageing concrete pipelines. Self-healing concrete, in the form of microcapsules filled with water treatment sludge, could be the answer.
Corrosive acid from sulphur-oxidising bacteria in wastewater, along with excessive loads, internal pressure and temperature fluctuations are cracking pipes and reducing their life span, costing hundreds of millions of dollars to repair every year across Australia.
“Sludge waste shows promise to mitigate microbial corrosion in concrete sewer pipes because it works as a healing agent to resist acid corrosion and heal the cracks,” Prof Zhuge says.
Deconvoluting Aluminum Alloy Corrosion with Multimodal Correlative Microscopy
Aerospace manufacturers are continuously exploring novel materials that could support the next generation of aircraft design. This includes advanced aluminum alloys that incorporate increased zinc content, which results in a tougher material with higher quench sensitivity. Unfortunately, these improvements often come at the cost of decreased cracking resistance. Understanding the precise source of environmentally assisted stress corrosion cracking (EAC) would allow manufacturers to finely tune alloy production and potentially overcome the shortcomings of these novel materials.
An Automated Approach to Detecting Corrosion Under Insulation
Corrosion under insulation (CUI) is corrosion that occurs in the base metal of piping, storage tanks, pressure vessels, and other assets when moisture penetrates the outer insulation. Corrosion and damage to the insulation are difficult to detect without the costly process of removing portions of it and performing an inspection. Standard techniques help identify damage in isolated areas but are resource intensive if prioritizing the overall condition of the asset.
Alternatively, robotics-based NDT techniques, such as Rapid Ultrasonic Gridding (RUG), reveal CUI through an internal inspection without the need for scaffolding or removing insulation. This technique utilizes ultrasonic testing to measure the thickness of the insulated metal. When paired with data visualization tools, the readings are used to generate 2D or 3D corrosion heat maps of the entire asset.