The Delhi Metro Rail Corporation Limited (DMRC) has issued a Letter of Acceptance (LoA)to M/s Afcons Infrastructure Limited for the work of Design and Construction of Tunnels Underground Ramp and Cut and Cover Tunnels Underground Metro Stations at Maa Anandmayee Marg, Tughlakabad Railway Colony and Tughlakabad on Aerocity Tughlakabad corridor of Delhi MRTS Project of Ph-IV
- Tender No: DC-07
- Name of the Contract: Design and Construction of Tunnels Underground Ramp and Cut and Cover Tunnels Underground Metro Stations at Maa Anandmayee Marg, Tughlakabad Railway Colony and Tughlakabad on Aerocity Tughlakabad corridor of Delhi MRTS Project of Ph-IV.
- Accepted Contract Amount: INR 16692096000.00
- Work Completion Period (in days): 1260
In May last year DMRC had invited a tender for Tender Number: DC-07.
Scope of work:
- Design and construction of Civil structural part of three underground stations namely Maa Anandmayee Marg, Tughlakabad Railway Colony, Tughlakabad Underground Stations along with entry/ exit structures, subways and associated structures such as ancillary buildings, Utilities galleries, AC plant room, ASS rooms, TVF rooms, system rooms and all other rooms, shafts, pump houses, water tanks, diesel generator set room or enclosure etc. as shown in GAD and tender drawings. Any temporary works associated with permanent works are also part of scope. The subways at few locations as shown in the General Alignment Drawings to be constructed by any method other than Cut & Cover Method.
- Design and Construction of Twin Bored Tunnels (UP & Down Line) of finished internal dia 5800 mm by Shield TBM in all types of Soil / Rock Strata/Mix Strata, starting near Tughlakabad Airforce Station and connecting Maa Anandmayee Marg Station, Tughlakabad Railway Colony Station, Tughlakabad Station and upto Sarita Vihar Depot Retrieval/Launching Shaft including Cross passages (Sump and without Sump), Sumps and drainage system as shown in GAD and Tender drawings.
- Design and Construction, in Soil/Rock Strata, of underground ramp beyond Sangam Vihar station from Up Line chainage 16144.757 to chainage 16368.627, twin tunnels (Up & Down Line) by Cut & Cover method (including launching shaft) from Up Line chainage 16368.627 to chainage 16488.130 near air force station Tughlakabad & Cut and Cover tunnel from UP line chainage 21586.752 to chainage 21761.158 (including launching/retrieval shaft) after Tughlakabad Underground station to accommodate the cross over and Cut and Cover tunnel from chainage 23061.261 to chainage 23125.788 near Sarita Vihar depot as shown in GAD and tender drawings including cross passages, sumps & drainage.
- All temporary works associated with permanent construction of the works including temporary steel decking over cut and cover structures, stations under roadways/service roads to allow uninterrupted flow of traffic/pedestrians. Construction and maintenance of temporary diversion roads and services for traffic diversion as required. Temporary walkway in TBM tunnels as required.
- Integration of proposed Tughlakabad underground station with the existing Tughlakabad elevated station and existing PWD sub-way with proposed entry/exit of Underground Tughlakabad station as shown in Tender drawing. All the works required for demolition/modification/reconstruction/remodeling in existing Tughlakabad Metro Station for integration with proposed underground metro station at Tughlakabad along with construction of connecting Foot Over Bridge/Connecting Passage is included in the Lump sum Price (Schedule A of BOQ). Further, All the works required for demolition/modification/reconstruction/remodeling for the integration of PWD subway with proposed entry/exit of proposed underground metro station at Tughlakabad as shown in tender drawing related to integration with proposed station is included in the contract.
- The contractor shall plan launching/ retrieval shaft inside the station box unless otherwise shown in the General Alignment Drawings and properly integrate the tunnel structure with the proposed station.
- All diversion works associated with construction of tunnel by Cut & Cover Method including design & construction of RCC box for the permanent drainage system.
- Waterproofing of all underground structures including walls of all entry/exits, ECS/TVS shafts, Plumbing shafts including Ancillary structures minimum 300 mm above final finished ground level, as per procedure mentioned in section 12 of OCS.
- Providing & Fixing Shear Connectors for Installation of the Rail Track both in Tunnel and Station Areas.
- Provision of one (1) tube well of 5-6 m3/hr yield for each station including providing and installing submersible pump of required capacity with all accessories including panels, cables up to main control panel in station, distribution box, GI pipe line, digital water flow meter, piezometer including connecting same to water storage tanks and ensure pump remain in good working condition up to Defect Liability period (DLP).
- Design and making provision of plumbing system for water supply, drainage and sewage in stations is in the Lump Sum scope. However, providing and laying of these plumbing pipes shall be paid separately under schedule B & C wherever required as per direction of engineer-in-charge.
- Design and Construction of tunnel drainage system is in Lump-sum scope except for following items:
- Providing and laying of drainage pipe from tunnel sump to station sump which will be paid under schedule B & C.
- Providing and installing pumps in tunnel sumps which will be provided by the E&M contractor.
- Make provision in structures for fire detection and suppression system and all other building services and designated contractor services.
- Make provision for accommodating the requirements for LV and MV supply routes for System wide Contractors and cable galleries / cable ways for all the cableways at the station and in the tunnel.
- Supply, delivery and installation, functional testing, and handover of earth mat as per tender drawing.
- Supply & Installation of all embedded pipes as per the requirement of system contractors is to be done by civil contractor. Installation of the embedded HDPE pipes as per requirement and as per instruction of Engineer-in-charge.
About Tunnel Boring Machine (TBM):
- A TBM is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata.
- They can be designed to bore through anything from hard rock to sand.
- TBMs have revolutionised the way tunnelling work is done all over the world as now tunnels can be bored without disturbing the buildings and other structures on the surface.
- TBMs are especially useful for underground tunnelling work in congested urban areas.
- DMRC has been using TBMs for its tunnelling work since Phase 1.
- In Phase 3, when about 50 kilometres of underground sections were built, about 30 TBMs were pressed into service in the national capital.
Source: DMRC-Tender Update | Image Credit (representational): DMRC
