The corrosion of buried infrastructure is a major problem and has significant economic impacts. Historically, the majority of pipelines, predominantly made from ferrous metals such as cast iron, were installed in the 1900s and are now highly susceptible to electrochemical corrosion. This susceptibility largely stems from their burial in soil environments not optimized for corrosion resistance. Initially, natural soils from excavation were used as backfill, which offered minimal protection against corrosion. However, from the 1960s onwards, the practice evolved significantly as specific materials like sand and various granular substances were increasingly utilised to enhance the structural support of pipelines.
Despite the advancements above, current backfill specifications primarily focus on structural integrity rather than mitigating corrosion. Additionally, recent research indicates that the role of backfilling in influencing pipeline corrosion has not been thoroughly investigated. Although methods such as cathodic protection offer a method to mitigate pipeline corrosion, it demands frequent maintenance and might induce corrosion in adjacent pipelines. Alternatively, engineered backfill materials present a viable, low-maintenance approach to effectively prevent corrosion in pipelines. To better understand the current industry requirements and perspectives, a survey was distributed across Australia, Canada, the UK, and the USA. The survey shows that industry professionals focus more on geotechnical factors like compaction level than corrosion concerns in their practices. The findings of the survey indicate that professionals commonly recommend methods such as enhancing corrosion protection, regular inspection and monitoring other than engineered backfills. Therefore, this study seeks to underscore the cost-effectiveness and benefits of using engineered backfill materials, incorporating recycled materials to aid in achieving net-zero carbon emissions. This approach presents a viable alternative to maintenance-intensive methods like cathodic protection.