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Tunneling
under the Najafgarh drain (Sahibi River) - An engineering
challenge
O.P.
Singh
To
extend the Metro from Vishwa Vidyalaya to Jahangirpuri,
1.1 km of tunnelling was required, including one underground
station and 5.2 km of an elevated section. Constructing
an underground tunnel presented some unusual constraints
at the drain crossing because the top of the underground
tunnel was almost at the invert level of the drain
and a three-span RCC slab supported on old masonry
piers served as a bridge at the tunnel crossing. Therefore,
construction methodology involved tackling the drain
and the bridge. The underground Metro corridor runs
under one-half of the existing carriageway.
The
deepest tunnelling in New Delhi for airport express
line
O.P. Singh
and P.K. Garg
The
Airport Express Line is about 22.7 km high-speed metro
connection between New Delhi Railway Station and Indira
Gandhi International Airport and extends upto Dwarka
sub city. The line has both underground and elevated
tracks. Therefore, the construction methods included
tunnelling by TBM, NATM, cut and cover and elevated
sections by launching of precast girders. This line
has a design speed of 135 kmph and is being built
on Public Private Partnership (PPP) model. Under this
model, the civil structures are in the scope of the
Government represented by Delhi Metro Rail Corporation,
and rolling stock supply, installation and operation
are in the scope of a private partner or concessionaire,
in this case, Reliance Infra- Caff Joint Venture (JV).
The concessionaire is required to manage the line
for 30 years and share revenue with Government.
Construction
of viaduct for metro express line using 25 m long precast
U girders - An experience
O.P. Singh,
S.C. Gupta and Amitabh Khare
The
Airport Metro Express Line is the first exclusive
line with dedicated check-in counters away from airport
at city centre and at city's main railway station.
The design speed of this line is 135 kmph with a provision
to increase it to 160 kmph. The line starts from New
Delhi railway station's Ajmeri Gate to Dwarika sector-21
via Indira Gandhi International Airport. It has six
stations namely New Delhi, Shivaji stadium, DhaulaKuan,
Delhi Airo city, IGI airport and Dwarika Sector-21
station. This 22.50 km project has 7.185 km elevated
corridor and the rest is underground.
Full
span precast pre-tensioned decks: The future of elevated
urban metro viaducts
Mangu Singh,
Rajan Kataria, Abdelghani Mhedden, Shahid Mohammad
and Purnima Bajpai
Delhi
Metro Rail Corporation (DMRC) is constructing the
Airport Metro Express Line as a fast, reliable, modern
and integrated connection between Connaught Place
and Indira Gandhi International Airport. This project
aims to provide relief from increased traffic congestion
experienced over the last few years. While most of
the line is underground, a part of it, from Vande
Matram Road to Palam, runs elevated on a railway viaduct.
To meet the completion target of 16-months, full span
construction method was used in this project. This
has resulted in increased speed of casting and erection
of the superstructure, compared to the standard precast
segmental construction method used nowadays in other
viaducts. This paper describes the technical features
of the full span deck. Another innovative solution
to further improve the speed of construction, namely
precast pier cap at top of pier, is also presented.
Optimised
long spans for urban railways projects
Kumar Keshav,
Rajan Kataria, Jean-Charles Vollery, Vaung Chhuo and
Abdel Mhedden
Metro
projects often face roads and river crossings, buildings
and monuments as obstacles in the urban environment.
Urban planners expect projects to integrate these
into the overall built environment. Also, solutions
in dealing with these should minimize impact on urban
life, construction schedule and interference with
the remaining parts of the project. Extradosed bridges
are an attractive solution in certain urban projects.
They allow building economical crossings over railway
lines and can have 40-120 m spans.
Construction
of INA to Jorbagh upline tunnel - Tunnelling in unfavourable
conditions - A case study
Sanjeev Malik,
Paras Kumar Agrawal and Umesh Billore
Tunnelling
using Tunnel Boring Machines (TBM) is a huge investment
in itself, but is often adopted for safe and speedy
construction. However, when unforeseen and unfavourable
conditions are encountered, it becomes important to
compare other available tunnelling methods also. In
this case a tough rock was encountered in front of
the TBM and an analysis of various available alternatives
was made to find a solution to progress with tunnelling.
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