The scope of this project entailed structural remediation to break-out and remediate 220 m2 of the wharf with spalling, carbonated or delaminating concrete, and repair with strong structural grouts on a deteriorating wharf in Salamanca, a prominent location in Hobart, Tasmania.
The repair methodology included the utilisation of VEC’s High Pressure Water Jetting Unit for hydro-demolition, and a complete concrete remediation system, including protection from incipient anode formation, steel augmentation, crack repair, form and pour and shotcrete.
Challenges - such as highly constrained under wharf access, and managing a deteriorating and inherently compromised structure during project works - are just a few of examples of how complex this project was. This, coupled with the intricate repair staging over the entire structure, are challenges that the VEC team were confronted with.
These challenges were overcome by staging multiple repair methodologies concurrently through the project construction period.
The access system utilised on this project comprised of suspended lightweight decks on rollers, lightweight aluminum scaffold and floating barges. Having steel forms for the beams was very beneficial, as this reduced the effort required to box entire beams. Steel form-works were developed for repetitious form and pour repairs on similar structural elements.
VEC considered and employed various methods to carry out the concrete repair methods, box and pour with holes drilled through the existing deck to enable the grout to fully fill the required area. Some areas required patching by hand; while larger areas were spray grouted using a Reed Sova, dry spray gunnite pump.
VEC also managed the hydro-demolition works that were within Salamanca, a prominent built up residents, touristic and business district. Effectively mitigating noise and access restrictions were critical to the success of this project. Intense and effective Stakeholder Management and community engagement were ways that the team were able to address any public queries.
The construction works under the wharf were heavily exposed to wind, waves and extreme varying tides, created multiple challenges of its own. The highly skilled team were able to work together to ensure the works were completed without a single Lost Time Injury.
The Client was very satisfied with the repair works performed by VEC, indicating that the works completed were some of the highest quality to date. This has been achievable in parts due to VEC’s use of a grout pump to mass pour up to 22 elements in one day, drilling through the wharf deck to pour grout through from the top, and shot-creting. This has made repairing the deck soffit effective and efficient, which would have otherwise been challenging.