Opal Tower Investigation – Interim Report

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Independent Advice to NSW Minister for Planning and Housing – 14th January 2019

Executive Summary

At the request of the Hon. Anthony Roberts, Minister for Planning and Housing, an investigation was carried out into the cause or causes of structural damage to the Opal Tower at Sydney Olympic Park, which was first observed at Christmas 2018.  The investigation also considered possible remedial action to repair the damage to the building. This interim report presents the preliminary findings of that investigation.

Further information is required to enable definitive conclusions to be made about the cause or causes of the damage to this structure and the proposed remediation. However, based on the information available to date the following opinions and findings of the investigation are presented:

  1. The building is overall structurally sound and not in danger of collapse, but significant rectification works are required to repair and strengthen damaged hob beams and in some cases panels that rest on them.
  2. A number of design and construction issues have been identified, a combination of which probably caused the observed damage to some structural members in the Opal Tower building. Further information is required to ascertain the relative materiality of these issues to the cause of damage.
  3. The viability of residents re-­‐entering the building extends beyond the structural issues considered here and hence beyond the scope of this investigation. Nevertheless, notwithstanding point 1 above, before residents re-­‐occupy the building the designers must ensure that no structural member is overloaded as a result of any load redistribution likely to have occurred as a consequence of the observed damage to the structure of the building.
  4. A proposal for staged rectification of the damaged structural members of the building has been considered and agreed in principle. However, it is recommended that independent and qualified structural engineers should be engaged to check the final proposal in detail before major rectification works commence.
  5. Further analysis should be undertaken on the structural design of the hob beams and associated structural members with similar details and consideration should be given to strengthening them wherever they occur throughout the building.



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