lnfracorr Consulting Pty Ltd (lnfracorr) assisted to resolve major structural deterioration issues at a 1950s high-rise apartment block at a coastal location. lnfracorr oversaw the project from start to finish, designing a comprehensive remediation solution to rehabilitate the structural columns and resolve the underlying waterproofing and drainage issues.

PROJECT HIGHLIGHTS

• The investigation of a 15-floor apartment block approximately 50 years old to uncover major structural deterioration.
• Design services to rehabilitate corrosion of the structural columns.
• Design services to resolve the waterproofing and drainage issues of the property.
• Infracorr oversaw the entire process from investigation to the completion of works.

CHALLENGES

• The project was a 50-year-old building with an implied life of 50 years.
• Poor waterproofing and drainage design on the balconies had resulted in coastal salts and moisture causing severe corrosion of the steel columns and other structural components over the 50-year life of the property.
• Moisture ingress to the steel columns had also compromised the fireproofing on the columns.
• “Lift-slab” building construction was unique in Melbourne. Slabs were used as formwork for the next slab. The slabs were then jacked and then fixed to the steel columns with pins and plates.
• The balconies balustrade height was not compliant with current safety requirements and code.
• As there were 60 balconies with different residents, access and works could only be completed practically from the outside of the property.

SOLUTIONS

Infracorr performed a thorough investigation to understand the issues and then design a comprehensive repair program.

The repair program designed included:

• Targeted structural steel column weld repairs to address the corrosion.
• Protective coatings and fireproofing to all structural steel columns where exposed on the balconies.
• A complete overhaul of the waterproofing and drainage systems for all balconies to ensure good drainage, alleviating the risk of water entry to the building and to structural elements.
• Upgrading the attachment of the concrete balustrades on all balconies, replacing old corroded steel brackets with stainless steel for safety and longevity.
• Removal of external decorative concrete features attached with corroding steel fixings.
• Galvanic anodes to protect embedded steel elements that were identified as a risk but not possible to remove.
• The addition of handrails to balustrades to ensure compliance to code and current safety standards.