The Bosphorus Rail Tube Crossing Project (MARMARAY) Design Services for Construction of the Tunnel and Stations Under Contract BC-1 (ru)

Brief Description of the Project :

The Project is based on rehabilitation of Istanbul suburban railway system, which will connect Halkalı on the European side to Gebze on the Asian side through a continuous, modern and high-capacity suburban railway system.

Railway lines on both sides of the Bosphorus will be linked through a submerged rail tube tunnel spanning the Bosphorus. The railway will enter under the ground in Yedikule, continue through the new underground stations Yedikule and Sirkeci, cross the Bosphorus under the sea and reach another new underground station Üsküdar and again emerge on the surface in Ayrılıkçeşme.

The Project is currently one of the largest transit infrastructure projects throughout the world. Length of the rehabilitated and new track system will be approximately 76 km in total. Main structures and systems will consist of 4 parts comprising the submerged tube tunnel, bored tunnels, cut-and-cover tunnels, at-grade structures, three new underground stations, 37 surface stations (rehabilitation and replacement), operations control centre, storage yards, workshops, maintenance facilities and a new surface third track and including upgrading the existing tracks, providing new electrical and mechanical systems and procurement of modern rolling stocks. A separate contract will be awarded for each part.

Scope of Services :

Contract BC1 covers the total 13.6 km section of the railway, starting at Kazlıçeşme Station and terminating after Ayrılıkçeşme junction.

For the structures detailed below;

• Architectural,
• Statical,
• Reinforced concrete / reinforcement,
• Excavation supporting,
• Infrastructure,
• Landscape, and
• Electro-mechanical design services are being provided.

Services will also be provided for;

• Earthing and anti-corrosion design (as a part of RC design),
• Seismic analyses,
• Damage assessment for the adjacent buildings and excavation supporting design,
• Reinforcement calculations for all designs,
• Preparation of design guidelines,
• Specifications for civil works
• Preparation of method statements

The design process is at three stages, namely conceptional design, final design and detail design.

Structures Being Designed:

Surface Stations

Kazlıçeşme Stations: Size: 225 x 11 m, Construction Method: Conventional

Underground Stations

Yenikapı TCDD: Size: 300 x 30.5 m, Foundation Depth (below existing ground level): 19.5 m, Construction Method: Cut and Cover

Yenikapı Station: Size: 242 x 30.5 m, Foundation Depth (below existing ground level): 20m
Construction Method: Cut and Cover

Sirkeci Station: Size : 225 x 50 m, Foundation Depth (below existing ground level): 54 m,
Construction Method: Cut and Cover + Bored

Üsküdar Station:  Size: 225 x 30 m, Foundation Depth (below existing ground level): 28 m,
Construction Method: Cut and Cover

Other Structures

Between Km 0+300 - km 4+080 and km 13+420 - km 13+860

• Cut and cover tunnels
• Bored tunnel portals
• Trackside structures on cuts and fills
• At grade trackside structures
• Trackside structures due to temporary and permanent route displacements for TCDD tracks
• Ventilation Buildings

-     Ayrılıkçeşme

-     Yedikule

• Bridges and interchanges

-     Yedikule railway bridge

-     Ayrılıkçeşme railway bridge

-     Ayrılıkçeşme Viaduct and Interchange (including the bridge and ring roads)

• Infrastructural facilities

Electro-mechanical design for all structures including tunnels but excluding ventilation under Contract BC1.