final-report-of-the-advisory-committee-on-falsework-bragg-report - Flipbook - Page 68
sites in the United Kingdom are several times more
numerous than those on civil engineering contracts.
The essentials of such a scheme are already practised
in the United States, Canada, Germany and elsewhere.
It may be worthwhile pointing out here that of all
European countries, the UK seems to be the only one
where the construction of a building does not invariably involve a direct link between the client and
the engineer.
The position under the standard form of contract for
building under the Joint Contracts Tribunal (formerly
known as the RIBA contract) is not satisfactory. The
evidence received by the committee seems to indicate
that architects would be content with a continuance
of the present, conveniently simple, arrangement
whereby no-one but the contractor is involved in any
way in the design of falsework. However, we cannot
be complacent about the large number of failures
which occur on building sites. Some of these might
have been prevented if there had been a professional
check on falsework designs which later experience
showed to be inadequate.
The necessary checking of falsework design on building
projects cannot always be carried out by a member
of the Architect's own organisation. Where the Architect has engaged the services of a consultant engineer
to co-operate in the production of a design for
permanent works then it would appear to be sensible
for the Architect to receive the contractor's falsework
proposals and to have these examined for him by the
same consulting engineer. This arrangement may
appear to be cumbersome but is forced upon us by the
fact that the consulting engineer has no standing in
the standard form of building contract and in many
cases the Architect does not possess the requisite
qualifications to undertake a falsework design check.
The only possible justification for the existing state
of affairs is that in the past many architectural designs
have presumed simple traditional methods of construction. This is not justified now that architects are
designing structures which are so much larger and
more complex. It may well be that future trends
towards standardisation of the structural elements in
a building will lead to a comparable standardisation
of procedure for the design of falsework. It would be
a fortunate concurrence if there were to be developed
a range of structural standards for buildings and
mpatible falsework design standards; this would
reduce the need for individual structural analyses
after the intial matched systems had been proved to be
successful from the design standpoint.
In the existing state of the building industry however,
few of the smaller contractors have staff capable of
undertaking a full design and the necessary calculations and drawings even using the resources of
specialist equipment suppliers. They must therefore
limit their work to the use of standard designs using
standard equipment in accordance with the technical
procedures which should be set out in the British
Standard Code of Practice on Falsework and expressly designed for contractors in this situation.
Modifications
Even when acceptable falsework drawings have been
produced, local circumstances may .necessitate modifications. There may be a shortage of the particular
material which a contractor planned to use; there may
have been an unforeseen circumstance that made it
necessary to transfer men and materials elsewhere;
there may be an unexpected need to provide openings
in the falsework for vehicular access or the passage of
service lines. The effects of flooding or storms may
necessitate re-appraisal of ground conditions. Such
modifications often have to be made very quickly. It
would be too onerous and, in most cases, unnecessary
for each and every minor departure from the agreed
drawings to be re-submitted for approval. But we have
abundant examples of last minute alterations, made
on the initiative of those on site, which have vitiated
the concept on which the falsework was based. The
vitally important thing is that the decision as to
whether a change needs to be referred back to the
designer is taken by someone competent to assess its
significance. Modifications which introduce significant
changes must also be referred back to the Engineer
for his acceptance. It is considered that significant
modifications should be made by issuing altered
drawings and withdrawing the originals rather than
by amendments of the originals on site.
The fact that a proper procedure for modifications
exists does not exonerate a contractor from doing all
he can to ensure that changes are not forced on the
construction team by bad planning; for a contractor
to argue that substitute material was used as he unexpectedly found that he was short of half a dozen
props, or that slightly undersized timber joists had
been delivered and that makeshift arrangements had
been used to overcome the deficiency, is simply an
admission of bad management. Satisfactory arrangements must be made in advance for storage, handling,
transport and, if necessary, hiring of materials.
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