Recently, AZ Alkmaar has published our report on the partial collapse of the AFAS stadium roof. With the help of Ender Ozkan from RWDI and Maarten Swinkels from SGS Intron we were able to reconstruct the collapse and determine the technical causes.
AZ’s General Director Robert Eenhoorn is very thankful towards Royal HaskoningDHV for examining the situation with such care: ‘The diligent efforts of Royal HaskoningDHV made very clear what exactly caused the partial collapse of the roof. ’Now this is clear we can continue building towards our future.’
Three weeks after the incident HaskoningDHV already presented its initial findings to AZ, after which a thorough investigation was conducted to be able to make a reconstruction of the incident and determine its cause. This included, amongst others, point cloud scans, lab research, wind tunnel measurements and NL-FEM analyses. Now, 8 months after the event, AZ has released the final Royal HaskoningDHV report which describes the findings of these analyses.
While the report includes an extensive examination and analysis of the situation, it boils down to the conclusion that there are 3 main reasons for the roof’s construction to fail:
- The main cause for the roof’s collapse is that the welds were too thin. A contributing factor were design flaws in the joints of the construction.
- Strong downward wind forces, which were not accounted for in the roof’s design, caused the roof to collapse.
- There is a high possibility that the construction was already weakened during a heavy storm shortly after the opening of the stadium.
As Robert Eenhoorn states, this knowledge is key in taking the next step towards a solution for the problem. He is looking forward to continuing operations and discuss new plans for the roof with all involved parties, after the corona crisis.
Image: Reconstruction image AFAS stadium