The Sunland Constructions high rise in Surfer’s Paradise, Queensland included the construction of two towers reaching 64 and 70 levels respectively.
The project started in July 2004 was from the ground level up to level 5 then excavation started on four basement car parks, for which a high strength concrete was required for columns and support walls of 80 and 60MPa. The request was for a super workable concrete that would compact with minimal vibration.
Consideration on design was given to the plastic properties of super workable concrete (S.W.C).
- Flow-ability in being able to pump down 4 levels of basement car parks
- Passing around reinforcement
- Segregation resistant to hold the mix together
- Bleed in pump lines and final form placement
The super-workable concrete mix was designed by Holcim to a w/c ratio with 10mm aggregate coarse and fine sand, GP cement, fly ash and Kaolite. Retarders and HRWR were also used for set control, which allows the concrete to be placed with out slump loss occurring.
The concrete production staff were trained in the importance of super workable concrete and strict plant control of w/c ratio produced a product that exceeded the client’s expectations and requirements.
On sourcing information worldwide, Holcim Technical Services developed an appropriate mix design and applied the relevant testing methods. Holcim succeeded in satisfying Sunland Constructions with a product not previously used in southeast Queensland prior to this project.