WATERPROOFING

The iconic Sydney Harbour Bridge has undergone major road maintenance. Completed ahead of the structure’s 80th anniversary on March 19, the works involved the application of a unique waterproofing system from Sika Australia in very challenging weather conditions.

The project aimed to prevent rainwater damaging the structural elements of the bridge, including the concrete bridge deck and steel support structure. Sika partnered with Concrete Remedial Services (CRS) to ensure the waterproofing application was delivered within a very tight schedule, minimizing service downtime on this high traffic roadway.

CONCRETE PRIMER AND SIKALASTIC®-841 ST POLYUREA SPRAY

Utilising a fast curing and hard wearing product combination, the Sika waterproofing system was lab tested and trialled on approx. 500 square metres eight months prior to the final application. The process involved Sika’s Concrete Primer and Sikalastic®-841 ST polyurea spray, resulting in a membrane that enables almost immediate return to service time. The membrane is specifically designed for waterproofing and anti-corrosion applications on steel, concrete and many other substrates.

BROADCAST INTO WET SURFACE: SIKALASTIC®-827 HT

An additional layer of an accelerated low viscosity epoxy resin has been applied as an adhesive for the final layer, Sikalastic®-827 HT pellets which were broadcasted into the wet surface to create a strong bond between the liquid applied membrane and asphalt concrete.

The new road surface is smoother and more durable, reducing the need for expensive reactive maintenance work in the future. Sika project manager Jamie Byrne said “The Sydney Harbour Bridge project was a highly technical job with heavy rain contributing to the difficult site conditions. Our solutions-focused and ongoing working relationship with CRS was a key part in meeting the deadline and ensuring the work is of a high standard.

WORKS AND REMEDIAL REPAIRS ON PUBLIC STRUCTURES

“This is the first time our unique waterproofing system has been applied to such a large scale and high profile landmark. Our team is proud to have its products chosen for the rejuvenation and protection of this Sydney icon,” added Byrne.

Sika Australia has been involved in a mass of major works and remedial repairs on public structures, both locally and internationally, with its core competency in sealing, bonding, damping, reinforcing and protecting. This has included joint sealing of the Sydney Opera House, the Victorian and Kurnell Desalination Plants and commercial properties such as the Coca-Cola offices and Coles Bay Luxury Resort in Tasmania.