REHAB & REPAIR
UV light train.
Thinking outside the box Far from the traditional circular and ovoid pipeline relining projects, Rangedale Rehabilitation and Renewals completes relining of two rectangular boxed culverts.
D
avid Dodemaide is the general manager of Rangedale’s Rehabilitation and Renewals (RRR) division, which specialises in trenchless rehabilitation and renewals. This arm of Rangedale has been operational since February last year, but Dodemaide has a full history in rehabilitation, having worked for 25 years with experts in rehab KA-TE, Inliner, Interflow, Comdain and Insituform. Rangedale Group Managing Director Neil Kermeen brought Dodemaide onboard to get the arm of the business going, and since then, the division has delivered a number of projects for local councils, other tier one/two organisations and water authorities. The most well-equipped drainage and civil services company in Victoria, RRR’s most recent innovative contribution to the industry has been a method for relining boxed culverts. Traditionally, most pipeline relining projects across Australia have been for circular or ovoid cross sections. Boxed culverts have been relined in the past, adopting slip lining methods whereby a liner is made-to-measure in the factory smaller than the existing culvert. The liner is then pushed or pulled through the existing structure, leaving a gap between new and old that is filled with grout. This smaller cross-section usually results in diminished hydraulic capacities after relining. Costs and construction times also increase due to the large
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volumes of grout required to fill the gap between old and new. Case study In February of this year, Rangedale Rehabilitation and Renewals was awarded a project by BMD Constructions, contracted by Major Road Projects Victoria. The contract was to design and construct the relining of two boxed culverts. RRR has previously been involved in joint projects with BMD, and had developed a strong working relationship with BMD. As a result the company was approached to carry out the relining of two boxed culverts. At 450 mm wide and 300 mm high, the two boxed culverts were requiring urgent repair works. The solution needed to be cost effective, meet the tight project timelines, ensured a 100year design life, and to not alter the hydraulic capacity of the newly installed drain. Rangedale offered a unique solution to BMD and the asset owner. A German-manufactured Saertex circular UV-cured, cured-in-place pipe (CIPP) liner is inflated to the highest pressure and formed to the rectangular shape of the culvert. The Saertex CIPP liner is designed in accordance with 100-year long-term properties and is deemed the best in its class with an extremely high stiffness modulus. The liner assumes the shape of the culvert.
Vertiliner project.
Small gaps left in the corners are filled with a highly flowable grout to further support the liner. The grout has no bearing on the structural integrity of the liner - it only adds additional support to the liner in the corners. Furthermore, the GRP liner surface is almost frictionless, providing the client with an increased hydraulic capacity after relining. The result exceeded expectations, and the company said it plans to use the technology on future projects.
