Civil Engineering Reference
In-Depth Information
were determined too often by the client and not by the contractor's assurance
organization. As a result, the client was obliged to put the emphasis more
on product assessments and to go from system and process-oriented moni-
toring to product control or even supervision.
A factor making the situation more difficult was that the contract did not
provide for the sanctioning of defects which had been determined during
the process and system assessments. Only when critical deviations of the
product were established, could payments be withheld.
In practice, it turned out that the contractor was still not sufficiently
familiar with working under external quality assurance. For the personnel
working on the primary process, quality assurance did not generally have
the highest priority; it was more important to bore and build as quickly as
possible. Due to the enormous financial interests that are at stake, the ques-
tion is justified as to whether it is at all desirable to carry out such a large
project under external quality assurance. The financial interests of a con-
tractor are so great that it is perhaps going too far to ask the contractor to
reject its own product if it does not meet the quality requirements.
The inadequate functioning of the quality assurance system has resulted,
within the experience of the Westerschelde Tunnel project as already
mentioned above, in the client altering the assessment strategy from moni-
toring at a distance to a stricter supervision, certainly when the essential
parts (which cannot be repaired later or capital intensive parts) of the pro-
ject were concerned. A big concomitant advantage of this is that the client
can have its own file; in the case of any claims, he can fall back on his own
observations.
Safety during the construction stage
In December 1999, a major accident occurred in the western tunnel tube:
four carriages loaded with concrete segments became detached and trav-
elled at high speed into the tunnel where they crashed into the back of the
tunnel boring machine. Fortunately, nobody was injured, but the material
damage was considerable. As a result of this accident, the Health and Safety
Inspectorate stopped the work for several weeks.
After the accident, the client adopted a much more active safety policy. In
addition to including safety care in the project plan, specific measures were
taken such as the formation of a 'Safety Collaboration Group' and the record-
ing of accidents for trend analyses and improvement measures.The analysis,
determination of trends and carrying out improvement measures was a
continuous process from that time.
Initially, the NV Westerscheldetunnel and KMW both had their own safety
teams, whereby the client's team checked the contractor's team. Both were
responsible for safety but could interpret this differently and also assess
(un)safe situations differently. With the setting up of the 'Safety Collabora-
tion Group', the two safety teams were combined, so that all expertise
and capacity was collected together and the topic of safety could be worked
on more efficiently and effectively. The team, in which a lot of expertise
was brought in from the process industry, consisted of so-called higher
safety experts, who worked part-time and under the supervision of the chief
quality assurance officer of the client and the responsible contractor's
group head.
The safety team focused on working out a series of specific measures, par-
ticularly with respect to the recording and analysing of accidents, incidents,
dangerous situations, promoting safety consciousness and drawing up
additional rules and regulations.
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