Geology Reference
In-Depth Information
contractor. As Walton (2007) observes, the contractor, unlike the
owner, is in the construction business, is a specialist in the particular
type of works he is to undertake, and may be able to spread the risk
over a number of contracts, to some degree. In order to get the
contractor to accept some of the risk of encountering dif
cult condi-
tions, however, the owner must expect to pay some additional sum to
cover that insurance element through a higher contract price; if the
risks do not materialise, he will have wasted money, but that is the
nature of insurance.
In shared risk contracts, the contractor is expected to accept and
cope with generally variable but predictable conditions, but is allowed
to claim for additional money where something unpredictable and
highly adverse is encountered. Despite the pressure release valve of
old ICE Conditions of Contract Clause 12 (payment for unexpected
ground conditions) and similar clauses in other standard forms of
contract, it is in all parties
'
interests that all hazards and risks are
foreseen and priced for by the contractor in terms of the extra work
and delay which will occur if the risk materialises. This is de
nitely the
province where the engineering geologist can play a major role and in
particular by engineering geologists working within the engineer
s
consulting team, which is responsible for investigating the site and
designing and specifying the works. There is a similarly important role
for engineering geologists within the tendering contracting company,
who must anticipate hazards and price the job sensibly.
Unfortunately, contractors sometimes fail to take account of all the
perceived risks (even where aware) partly because they know that the
owner (advised by the engineer) will be tempted to employ the con-
tractor offering the lowest price. There are Machiavellian aspects to all
this in that each party is trying to minimise its costs and risks whilst
maximising pro
'
t. Contract writing and interpretation are key parts of
this. For example, a contractor will try to predict where extra quan-
tities might be required during construction, compared to the estimates
by the engineer that will form part of the contract in the BOQ
(for example, in the proportion or rock vs. soil to be excavated) and
quote unit prices appropriately to maximise his pro
ts. He might
include high mobilisation charges, whilst trimming prices of other
items on the bill to improve the payment schedule and his cash
ow
without jeopardising his chance of winning the contract in competition
with other invited tendering contractors. This is all fair and above
board but it does mean that the conduct of a civil engineering contract
can be rather fraught at times.
It is now common, for tunnelling works especially, to try to set out
some reference ground conditions (presented in geotechnical baseline
