Introduction | Ground
Conditions | Construction Stages | Slideshow
| Exercise
Underground Car Park
These notes will take you through the construction sequence of an underground
car park constructed in a soft alluvial deposit close to a retaining wall.
The retaining wall around any deep excavation needs to be braced to prevent
the wall deflecting inwards and causing settlement behind the walls which
may cause damage to nearby structures. Top down construction uses the floor
slabs to brace the walls. To achieve this, the slabs must be cast before
excavating the basement. Columns
are needed to support the slabs, so these must be constructed first. The
most unusual feature in this case history is the use of steel
sheet pile walls in place of the more usual concrete diaphragm
or secant pile wall.
This exercise has been selected to provide you with a realistic geotechnical
background, against which you will use your common sense to make simple,
practical engineering judgements, and also so that you can apply what you
will learn about the various fundamental aspects of soil mechanics.
Understanding, combined with a practical perspective on this basic knowledge,
is absolutely vital to allow you to graduate into solving the real geotechnical
problems that lie within any civil engineering project.
You will be asked, at various stages of the course, to give your engineering
opinions and to make some simple calculations. At times, your previous
answers may be re-presented to you, so that you can revise and resubmit
your thoughts in the light of further knowledge. As such, it is intended
that there will be a self-discovery element in this part of the
course, there are no absolutely cut and dried correct answers. Discussion
with colleagues is encouraged although each student is expected to give
his/her own individual answer.
The information
contained in this web page (and in other web pages that are linked to it)
is based on the Bristol 2000 Underground Car Park in the centre
of Bristol near the Floating Harbour. The
car park was designed by Ove Arup and built between January 1998 and Autumn
1999 at a cost of SFr25 million (excluding landscaping costs), using top-down
construction.
The original version of the web
site was developed by Leslie
Davison, University of the West of England, Bristol in November 1999,
using drawings and photographs supplied by Ove Arup & Partners (Bristol
Office). The original drawings for the various construction stages were
done by Andrew Dyer.
The web site was subsequently modified
by Jitendra Sharma in August
2000 and translated by Robert Banjac for this course. Deliberate changes
were made to some of the details to make the case history more relevant
for typical geological conditions in Switzerland.