VEC pay close attention to the durability requirements of piling work and access requirements, including piling in areas with poor ground conditions.
The replacement structure comprised of a line of AZ-38 sheet piles supporting a 300 mm thick concrete slab with a new diesel bowser and significant provision for future underground services. TasPorts requirement to maintain working access to the wharf and wharf-mounted diesel bowser necessitated construction of the new structure in 2 separable portions. Construction works occurred in a 9 stage process:
- Site establishment, survey and geotechnical investigation: VEC employed local site knowledge.
- Piling: existing timber piles were removed and structural steel piles were driven in front of the existing wharf piles.
- A protective concrete shield was poured behind the seawall to meet corrosion criteria.
- Drainage and service pits were installed in accordance with client specifications.
- Electrical and fuel services were relocated in close coordination with TasPorts.
- The new slab was prepared insitu and placed.
- Insitu kerb formed over water and poured to tie in sheet pile wall.
- Fender piles were driven using a rubber tracked excavator and fixed into position with stainless steel straps.
- After Stage 1 was completed, Norton’s Jetty access was momentarily cut and replaced with a temporary access gangway for the duration of Stage 2 works. On completion of Stage 2 works, access to Norton’s Jetty was permanently reinstated as part of the new structure.
Community stakeholder liaison was a daily challenge on the project with fishermen, BP tankers, tourism operators and curious tourists all requiring clear communications. Effective communication resulted in no recorded public complaints.