DFI Magazine September/October 2020 - 108

Mechanized excavation was adopted for
the tunnels, which have inner diameters of
37.4 ft (11.4 m) and lengths of approximately 1.5 mi (2.8 km). A Mixshield TBM
was used for each tunnel, which has an
excavation diameter of 42.6 ft (13 m).
Finally, plastic diaphragm walls were executed for the break-in and break-out blocks.
The project also included six cross
passages (CP1 to CP6) connecting the two
tunnels that were executed with plastic
diaphragm walls. Three of these cross
passages functioned during construction as
emergency exits and were used to carry out
maintenance interventions at the TBM front.
The main contractor (AC-OCI JV)
awarded the special foundations works to
construct the north-side road tunnel to
Trevi, in a joint venture with The Arab
Contractors (AC). The work began in
September 2015.

Soil Profile
The site area for the special foundation work
is basically flat, with ground level ranging
between +4.9 to +6.6 ft (+1.5 to +2.0 m)
above mean sea level. The static level of the
water table coincides with the sea level.
Soil investigations carried out to define
the stratigraphic conditions of the area
showed a rather uniform stratigraphy
along the entire axis of the road tunnels. In
particular, the soil consisted of two
geological formations:

Tunnel longitudinal profile and plan view

108 * DEEP FOUNDATIONS * SEPT/OCT 2020

Guide wall construction for multicellular launching shaft

1) Fine materials derived from recent river
deposits (Holocene) of the Nile Delta.
This normally consolidated, silty clay
has a consistency ranging from very soft
to firm for the first 131 to 141 ft (40 to
43 m) below ground level.
2) Below that (starting 131 to 141 ft [40 to
43 m] below ground level) lies coarsegrained materials belonging to older
Pleistocene deposits. This medium to
very dense silty sand extends to the
maximum investigated depth. This
layer includes lenses of very stiff to hard
silty clay, at different depths and with
varying thickness.

To provide appropriate support for heavy
excavation equipment in the working area,
a fill that consisted of granular material
properly leveled and compacted was
executed. Its thickness ranged from about
6.5 to 11.5 ft (2.0 to 3.5 m) on the east side
and from 11.5 to 16.4 ft (3.5 to 5.0 m) on
the west side of the road tunnel construction site.

Launching/Reception
Shafts Development
The geological conditions of the site led the
consortium to install diaphragm walls by
using something other than a hydromill,



DFI Magazine September/October 2020

Table of Contents for the Digital Edition of DFI Magazine September/October 2020

CONTENTS
CONTENTS 2
DFI Magazine September/October 2020 - Intro
DFI Magazine September/October 2020 - 1
DFI Magazine September/October 2020 - 2
DFI Magazine September/October 2020 - CONTENTS
DFI Magazine September/October 2020 - 4
DFI Magazine September/October 2020 - CONTENTS 2
DFI Magazine September/October 2020 - 6
DFI Magazine September/October 2020 - 7
DFI Magazine September/October 2020 - 8
DFI Magazine September/October 2020 - 9
DFI Magazine September/October 2020 - 10
DFI Magazine September/October 2020 - 11
DFI Magazine September/October 2020 - 12
DFI Magazine September/October 2020 - 13
DFI Magazine September/October 2020 - 14
DFI Magazine September/October 2020 - 15
DFI Magazine September/October 2020 - 16
DFI Magazine September/October 2020 - 17
DFI Magazine September/October 2020 - 18
DFI Magazine September/October 2020 - 19
DFI Magazine September/October 2020 - 20
DFI Magazine September/October 2020 - 21
DFI Magazine September/October 2020 - 22
DFI Magazine September/October 2020 - 23
DFI Magazine September/October 2020 - 24
DFI Magazine September/October 2020 - 25
DFI Magazine September/October 2020 - 26
DFI Magazine September/October 2020 - 27
DFI Magazine September/October 2020 - 28
DFI Magazine September/October 2020 - 29
DFI Magazine September/October 2020 - 30
DFI Magazine September/October 2020 - 31
DFI Magazine September/October 2020 - 32
DFI Magazine September/October 2020 - 33
DFI Magazine September/October 2020 - 34
DFI Magazine September/October 2020 - 35
DFI Magazine September/October 2020 - 36
DFI Magazine September/October 2020 - 37
DFI Magazine September/October 2020 - 38
DFI Magazine September/October 2020 - 39
DFI Magazine September/October 2020 - 40
DFI Magazine September/October 2020 - 41
DFI Magazine September/October 2020 - 42
DFI Magazine September/October 2020 - 43
DFI Magazine September/October 2020 - 44
DFI Magazine September/October 2020 - 45
DFI Magazine September/October 2020 - 46
DFI Magazine September/October 2020 - 47
DFI Magazine September/October 2020 - 48
DFI Magazine September/October 2020 - 49
DFI Magazine September/October 2020 - 50
DFI Magazine September/October 2020 - 51
DFI Magazine September/October 2020 - 52
DFI Magazine September/October 2020 - 53
DFI Magazine September/October 2020 - 54
DFI Magazine September/October 2020 - 55
DFI Magazine September/October 2020 - 56
DFI Magazine September/October 2020 - 57
DFI Magazine September/October 2020 - 58
DFI Magazine September/October 2020 - 59
DFI Magazine September/October 2020 - 60
DFI Magazine September/October 2020 - 61
DFI Magazine September/October 2020 - 62
DFI Magazine September/October 2020 - 63
DFI Magazine September/October 2020 - 64
DFI Magazine September/October 2020 - 65
DFI Magazine September/October 2020 - 66
DFI Magazine September/October 2020 - 67
DFI Magazine September/October 2020 - 68
DFI Magazine September/October 2020 - 69
DFI Magazine September/October 2020 - 70
DFI Magazine September/October 2020 - 71
DFI Magazine September/October 2020 - 72
DFI Magazine September/October 2020 - 73
DFI Magazine September/October 2020 - 74
DFI Magazine September/October 2020 - 75
DFI Magazine September/October 2020 - 76
DFI Magazine September/October 2020 - 77
DFI Magazine September/October 2020 - 78
DFI Magazine September/October 2020 - 79
DFI Magazine September/October 2020 - 80
DFI Magazine September/October 2020 - 81
DFI Magazine September/October 2020 - 82
DFI Magazine September/October 2020 - 83
DFI Magazine September/October 2020 - 84
DFI Magazine September/October 2020 - 85
DFI Magazine September/October 2020 - 86
DFI Magazine September/October 2020 - 87
DFI Magazine September/October 2020 - 88
DFI Magazine September/October 2020 - 89
DFI Magazine September/October 2020 - 90
DFI Magazine September/October 2020 - 91
DFI Magazine September/October 2020 - 92
DFI Magazine September/October 2020 - 93
DFI Magazine September/October 2020 - 94
DFI Magazine September/October 2020 - 95
DFI Magazine September/October 2020 - 96
DFI Magazine September/October 2020 - 97
DFI Magazine September/October 2020 - 98
DFI Magazine September/October 2020 - 99
DFI Magazine September/October 2020 - 100
DFI Magazine September/October 2020 - 101
DFI Magazine September/October 2020 - 102
DFI Magazine September/October 2020 - 103
DFI Magazine September/October 2020 - 104
DFI Magazine September/October 2020 - 105
DFI Magazine September/October 2020 - 106
DFI Magazine September/October 2020 - 107
DFI Magazine September/October 2020 - 108
DFI Magazine September/October 2020 - 109
DFI Magazine September/October 2020 - 110
DFI Magazine September/October 2020 - 111
DFI Magazine September/October 2020 - 112
DFI Magazine September/October 2020 - 113
DFI Magazine September/October 2020 - 114
DFI Magazine September/October 2020 - 115
DFI Magazine September/October 2020 - 116
DFI Magazine September/October 2020 - 117
DFI Magazine September/October 2020 - 118
DFI Magazine September/October 2020 - 119
DFI Magazine September/October 2020 - 120
DFI Magazine September/October 2020 - 121
DFI Magazine September/October 2020 - 122
DFI Magazine September/October 2020 - 123
DFI Magazine September/October 2020 - 124
DFI Magazine September/October 2020 - 125
DFI Magazine September/October 2020 - 126
DFI Magazine September/October 2020 - 127
DFI Magazine September/October 2020 - 128
DFI Magazine September/October 2020 - 129
DFI Magazine September/October 2020 - 130
DFI Magazine September/October 2020 - 131
DFI Magazine September/October 2020 - 132
DFI Magazine September/October 2020 - 133
DFI Magazine September/October 2020 - 134
DFI Magazine September/October 2020 - 135
DFI Magazine September/October 2020 - 136
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/september-october-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/Jan-feb-2021_nxtbook
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/september-october-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/sept-oct-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-aug-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/September-October-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2020
https://www.nxtbookmedia.com