Geology Reference
In-Depth Information
parties are governed by contracts. A contract is a legal document
between the owner and each of the other parties involved with a project
and de
cation of works, including payment
schedules and responsibilities. Contracts also need to be made between
consultants and specialist sub-consultants or JV partners, and between
a contractor and specialist sub-contractors. It is very wise to use lawyers
at this stage to ensure that contracts are well written to minimise the risk
of later dispute, although standard forms of contract are often used and
large companies tend to have internal documents. The experienced
engineering geologist can help ensure that contracts are reasonable,
realistic and fair with respect to their treatment of ground conditions,
which is where many problems arise during construction. These pro-
blems need to be resolved in a pragmatic manner and quickly during
construction, but there is often some dispute at a later stage over which
party should pay for changes, additional costs and delays.
nes the scope and speci
As discussed later, sites vary geotechnically from those that are extre-
mely dif
cult to understand and characterise, to those that are simple
and straightforward. In a similar fashion, site investigations vary in
quality from focused, excellent and insightful, to downright useless,
depending on the experience, capability and insight of the engineer
and his team in planning and interpreting the investigation and the
skill and quality of equipment of the ground investigation contractor.
As a result, there are always risks involved in projects, especially
where these involve substantial ground works, for example, in tunnel-
ling or deep foundations. The risks need to be assigned under a
contract and there are few mandatory rules. Each contract should
state how variations are to be dealt with in the event of unforeseen
ground conditions such as stronger or weaker rock (requiring differ-
ent excavation techniques) or more water in
ow to a tunnel (requir-
ing additional ground treatment works) than had been anticipated.
This is a large and important subject and guidance on how to identify
critical ground conditions through a systematic approach for addres-
sing hazards and risks, using focused site investigation, is presented in
Chapters 4
and
6
and Appendix E.
Chapter 7
takes this further and
provides case examples of projects where things went wrong for some
reason or other.
Some of the background and options for preparing a contract with
respect to ground hazards are illustrated in
Figure 2.2.
Mostly, projects
use standard contract forms such as the New Engineering Contract
(NEC) (ICE, 2005) or Fédération Internationale Des Ingénieurs-
Conseils (FIDIC) (discussed by Tottergill, 2006). Some contractual
forms are suitable to engineer-design contracts and others to design
and build situations.
