Regional spotlight series: meeting the demand for specialised applications and civil infrastructure remediation in Victoria and Tasmania

The geographical area in Victoria and Tasmania includes thriving cities, sprawling low density suburban areas and vast rural farmland, with geotechnical challenges spanning residential and commercial development to major civil infrastructure projects. Our team specialises in identifying and solving a wide range of ground engineering and remediation issues, such as ground re-levelling and soil strengthening, concrete repair and specialist grouting, as well as specialised resin coatings and waterproofing solutions.

The soil composition in Victoria and Tasmania also varies from reactive clay, common in urban areas including metropolitan Melbourne, to sandy and loam soils which are found throughout the state. In contrast, Tasmania contains a more diverse range of soils due to the state’s landscape and geology.

Maintaining assets and critical infrastructure

Infrastructure, civil remediation and concrete repair have become a growing area of focus for our business, perhaps more so here than in any other region in Australia after the Victorian Government announced a $90.2 billion investment into local infrastructure projects over the next four years[1]. Mainmark has consistently demonstrated how our products and expertise are more efficient and cost effective when addressing geotechnical and asset remediation challenges for these sectors.

Commercial remediation projects that require ground improvement works are an important part of Mainmark’s operation, such as this multi-storey business complex in Victoria which was saved from subsidence using our proprietary JOG Computer-Controlled Grouting and Teretek^®. The geotechnical site survey revealed that the complex was built on a combination of fill material and highly reactive clay. Water ingress had caused the clay to heave, resulting in building movement and damage to the buildings.

Many single and multi-storey developments experience subsidence due to water ingress, as excessive water can oversaturate and soften the soil underneath foundations. Reactive clay is particularly susceptible to subsidence as the soil swells and shrinks in response to changing moisture levels, which reduces ground bearing capacity and exacerbates the risk of differential soil settlement.

Decommissioning old or damaged pipe infrastructure, including redundant gas, water and sewer pipes, can also be problematic, particularly in inner city areas and older suburbs where ageing infrastructure has started to crack and leak, releasing water into the ground. These pipes cannot be easily removed without impacting the surrounding environment. This is particularly challenging if the pipes are located below roads and rail tracks as the disruption would not only result in the lengthy closure of essential transport corridors but would also be cost prohibitive. For this reason, they usually remain in the ground.

However, abandoned pipes cannot simply be left to deteriorate underground without being filled with an appropriate inert solution. If the pipe was to collapse or if water leaked into the surrounding ground, subsidence and erosion could lead to dangerous voids and sinkholes. Filling redundant pipes with a highly flowable structural fill material, such as Mainmark’s Terefil®, which is designed to be pumped further and faster than traditional concrete fill solutions, is providing a new way to solve the problems associated with pipe abandonments. Projects like the abandoned cast-iron gas main in Brunswick and the ground stabilisation and void fill at a stormwater deck replacement in Fitzroy, particularly benefited from our specialist solutions.

How the pandemic has impacted operations

While COVID-19 has impacted many businesses across the country, including Victoria which experienced numerous hard lockdowns and ongoing restrictions, Mainmark’s civil infrastructure division continued to experience high demand due to our range of specialised applications that are used for projects classified as critical infrastructure.

Mainmark’s reputation as a civil remediation expert has helped maintain the pace for the business, following the completion of a variety of successful projects across Victoria and Tasmania. Back in 2019, Mainmark stabilised the heritage listed Kimberley Rail Bridge in Tasmania by using Teretek to fill underwater voids. This work forged strong relationships with infrastructure maintenance contractors, leading to our range of bespoke solutions being specified for recent major capital works projects such as The West Gate Tunnel, Western Roads Upgrades and the North East Link.

Research and innovation keep Mainmark at the forefront of ground engineering

Mainmark’s innovative products like Terefil®, Teretek®, JOG and specialised engineered coatings and waterproofing solutions have consistently proven over time to be more cost-effective and time-efficient compared to more traditional remediation alternatives. This has resulted in Mainmark fast becoming recognised as the region’s ‘go-to’ contractor for complex problems.

Research and development have become a crucial reason why Mainmark delivers, and exceeds, customer expectations. Products and advanced delivery methods are continually being developed and tested to ensure the applications are tailored to Australia’s ground and civil remedial challenges. This involves quality assurance and stress tests that push the product’s individual capabilities.

The expertise and tailored solutions-focused approach from Mainmark helps project managers and asset owners across the wider region realise the deeper value and insight that ground engineering specialists can provide. This has steadily strengthened Mainmark’s following and increased our reputation as a reliable problem solver throughout the industry and the local community.

[1] https://infrastructure.org.au/wp-content/uploads/2021/05/MEDIA-RELEASE-PALLAS-DELIVERS-HIGHEST-INFRASTRUCTURE-SPEND-ON-RECORD-SETTING-THE-STATE-ON-STABLE-PATH-TO-RECOVERY.pdf