Environmental Engineering Reference
In-Depth Information
Project and technical assistance to the retaining structures
of cabo Girão Tourist Resort
F.a. sousa, c.J.o. Baião & J.M. Brito
Cenorgeo, Engenharia Geotécnica, Lda., Lisboa, Portugal
aBsTRacT: Due to the existing conditionings for the implantation of the different areas that comprise
cabo Girão Tourist Resort, at Madeira island, namely the vigorous relief and the geological-geotechnical
conditions, it was necessary to conceive an important group of retaining structures, using different solu-
tions, varying from gravity and semi-gravity cyclopean concrete structures to reinforced concrete walls
and soil nailed walls or nailed slopes. This paper presents the conception of the project in its different
stages and the main activities developed under the scope of the special technical assistance provided dur-
ing the execution phase.
1
caBo GiRÃo ToURisT ResoRT
GeneRal DescRiPTion
a total of 40 retaining structures and slope con-
solidation structures were built, in a total length
higher than the one defined for the tourist com-
plex streets' network, being therefore necessary
to implement several different solutions, namely
gravity and semi-gravity cyclopean concrete walls,
reinforced concrete walls, soil nailed walls and soil
nailed slopes. it is important to emphasize the
influence of the retaining structures in the final
cost of this type of work, of about 15%, revealing
the importance of all the involved studies.
The cabo Girão Tourist Resort, with an approxi-
mated total area of 65000 m
2
, is located 580 m
above the sea level, at Madeira island, comprising
a multi-services area (n1 block), four residential
areas (n2 to n5 set of blocks) and a leisure area
The total construction area of the tourist com-
plex is of about 41100 m
2
, placed between the
areas defined by the regional road which crosses
the complex.
The building of the n1 block, named the “main
building” is a four storeys building, being two of
them semi-underground storeys, and is located
in the central area of the tourist complex. it is a
leisure building, offering an exterior leisure area
with two swimming pools and other equipments.
The n2 to n5 blocks are placed around the main
building, being the n2 block located west, com-
prising 5 buildings, and the n3 block located
north, with twenty-one buildings, the n4 block
located east, comprising a group of seven three-
storeys buildings. The n5 block comprises twenty-
one two-storey dwellings (six of them twin-houses)
and is located in the southern area of the complex.
The n6 block defines a leisure area with swimming
pool and tennis court, being located at the west
To create and make possible the implementa-
tion of these construction areas and respective
infrastructures it was necessary to build several
platforms on the existing terrain, which were held
by significant excavation and landfill retaining
structures.
2
GeoMoRPholoGY, GeoloGical
anD GeoTechnical conDiTions
The resort is located on a long and angled slope ori-
ented to the sea, with a north-south gradient, and
abruptly cut off by the cabo Girão cliff, with an
unevenness of approximately 550 m. The average
slope angle is between 20º and 30º and presented
several old retaining walls, being crossed by a feeder
road. The tourist complex was developed between
levels 510 and 610 m, in an area with an unevenness
of approximately 100 m.
The project paid special attention to the results
obtained from the geotechnical investigation of
the geological and geotechnical study (cenorgeo
2003a), which included 19 rotation boreholes,
executed throughout the resort area. according
to this study one verified that some cover deposits
occurred at the surface, resulting from the weather-
ing process of the subjacent formations, which are
mainly formed by volcanic bombs levels, covering
mostly the resort northern area.
