Cook Costello’s response to the original questions posed are as follows:
1. Review the Structex report and the documents provided.
i. The Structex reports detail a repair or rebuild methodology and also includes an examination of the precast panel connections and a geotechnical report. ii. The examination of the precast panel connections concluded that they were below the requirements of AS1170.5:2004. These conclude that the precast panel connections are below the requirements of AS1170.5:2004. iii. The Geotechnical Investigation Report conducted a site investigation included observations of building and land damage, 4 Cone Pentrometer Tests, 4 Hand Augerholes and 4 Scala Penetrometer Tests on the site. …show more content…
Therefore, a review of the original calculations would be advised as the most expedient method of achieving an answer.
The structural adequacy of these elements should have been included in the Producer Statement 1 of the original building engineers.
v. Cook Costello have checked the wall bracing along the frontage of the building. The wall bracing along the frontage consists of 16mm reidbrace. This appears to be inadequate to support the lateral loads (east-west direction) along the frontage (giving a tensile load of 200kN compared to its capacity of 116kN). Cook Costello found that the design capacity of these elements are approximately 70% of the demand (using NZS4203:1992). The roof bracing (consisting of a mixture of 16mm reidbrace and 20mm reidbrace) is also inadequate to transfer the forces to the rear concrete walls as an alternate load path.
The structural adequacy of these elements should have been included in the Producer Statement 1 of the original building …show more content…
vii. The steel portal frames appears to be of inadequate stiffness to satisfy the stiffness criteria of NZS4203:1992 (for the Serviceability Limit State). This limit is intended to help prevent damage from where the portal frames deflect relative to relatively stiff elements (such as the end walls or where the frontage protrudes in this case).
Of similar note, the maximum interstorey drift criteria is not met. However, as this is a single storey building, this is not considered as critical.
The structural adequacy of these elements should have been included in the Producer Statement 1 of the original building engineers.
4. Any further advice or views as required?
- The building experienced a Scaled Peak Ground Acceleration of near its Ultimate Limit State (as per NZS1170.5). The structure would have been expecting to have been damaged by this event. However, the damage would have been exacerbated by the lack of structural adequacy and geotechnical design in the original building. Therefore, while a degree of damage would have been expected, it would have been likely to be damage to a lesser extent as