Learn from mistakes made by others so you will not make the same for your projects
It was reported in June 2009, in Kuala Terrengganu, Malaysia, that the roof of a RM300 mil (US $90 mil) Sports Stadium collapse suddenly just after it was recently completed.
No one was injured, The damage was extensive, as practically the whole east wing came crush down at 8am in the morning, a few cars were damaged. The contractor was a South Korean Company while the Consultants were local Malaysians. The Repairs were carried and costs about RM35mil (US$10mil).
Since the works were still within the defects liability period which is usually 12 months or more for such a massive project, the cost of remedial works were borne by the Contractor. What other issues involved would be under the relevant authorities.
An Investigation Committee was immediately set up with involvement from the Public Works Department, Ministry of Works, Related Agencies, Experts, and an extensive report was later compiled.
Some of the photographs of the roof stadium collapse would be revealing :-
Aerial Picture of the Collapsed Roof. Note that the other structures are intact, it is only the roof which failed and the roof is actually a Proprietary Space Frame Structure, and not designed and fabricated by local contractors on site. Note also that Space Frames are all Pinned Jointed and designed based on direct forces, tension or compression. |
Part of the Roof Structure which shows the Space Frames involved |
More pictures showing the extensive collapse of the whole roof.Note that Space Frames are interdependent on each other for strength. It is very weak and unstable until it is erected and forces are transmitted from top down. It is also very sensitive and any failure would be more of a "domino effect" |
Extensive Lives would have been lost had the Sports Stadium been occupied during the Malaysia Games ! Designers and particularly Structural Engineers must be acutely aware that any structures you do must never fail under any circumstances, as any failures could result in collapse and lost of lives, not to say very costly.
Causes of Collapse of the Roof Structure
The Reports by the Investigation Committee highlighted a few factors which could have contributed to the failure of the roof structures as summarised below :-
- The design was inadequate
- The roof was not erected properly resulting in misalignment
- No quality control on Site
- Materials and Workmanship not in accordance to specifications
- Alternative designs from Contractor was adopted without proper analysis
The above sounds too familiar and so common in our construction industry. Almost every sites are faced with these issues. In fact, structures are very resilient and would not have been catastrophic in collapse, even if under designed. The concept of limit state design takes account of this, allowing collapse to be progressive rather than catastrophic. Only steel framed structures are more prone to collapse especially during erection period, and particularly for 3D space frame structures.
The BIG Question is "Who is responsible for this?"
It is natural for everyone to point at the Contractor first and then the Consultants, but in many cases the Employer or Owner are to be blamed. Investigations can never be final and the cases will drag on for ages usually to the courts. The best approach is to AVOID this ever happening to you and your projects, whether you are a Contractor, a Consultant or an Employer. In almost all cases, this can be avoided.
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