By Pierre Verhaeghe, Project Engineer specialising in Wind Engineering here at Holmes Consulting.
The Commercial Bay tower in Auckland is currently the tallest office building in New Zealand. This article presents
the methodology followed by the structural designer to assess the wind loads. It summarises the key wind principles
and the wind tunnel tests methodology used in the assessment. It is shown that the methodology of the New
Zealand Standard for Wind Loading was successful in predicting the wind loads and the dynamic response of the
building, highlighting early in the design process potential risks of excessive accelerations, although the method of
the National Building Code of Canada was needed to complement the assessment. In comparison with its European
counterpart, the New Zealand Standard methodology provides the structural designer with efficient tools such as
the direct estimation of the floor-by-floor wind loads, cross-wind accelerations and reference to suitable occupant
comfort criteria. The article highlights how the structural designer made use of different methods available at different
stages of the project and the importance of integrating the wind loading assessment in the design process.