Excavation and Support Categories of Natm
Excavation and Support Categories of Natm
Excavation and Support Categories of Natm
About Me
Studied at Hacettepe University First Summer Practice: Turkish Coal Enterprises Garp Lignites Establishment Second Summer Practice:Koza Gold Operations Company e-Mail: zeynep_seker@live.com Phone number: 0 555 706 61 53
THE NEW AUSTRIAN TUNNELLING METHOD (NATM), AN ALTERNATIVE AND CHEAPER WAY FOR TUNNELLING
History of NATM
NATM was developed between 1957 and 1965 in Austria. The main contributors to the development of NATM were Ladislaus von RABCEWCZ, Leopold MULLER and Franz PACHER.
MAIN IDEA!
The main idea is to use the geological stress of the surrounding rock mass to stabilize the tunnel itself!
Philosophy of NATM
Design as you go!!
Not too stiff. Nor too flexible Not too early,Nor too late
1. 2. 3. 4.
Theoretical excavation line 5. Immediate support 6. Foundation Lateral drainage pipe covered 7. with porous concrete
Waterproofing system Final unreinforced concrete lining Main tunnel drain pipe covered with porous concrete
8. 9. 10. 11.
Sidewalks with/without utility conduit Precast gutter curb Road surface Ventilation fans
Cross Section
SPOT BOLT
SEALING SHOTCRETE OUTLINE OF ORIGINAL TUNNEL
Bergen Tunnel
SHOTCRETE
Zederhaus Tunnel
TEMPORARY INVERT
Cross Section
SHOTCRETE
Lattice Girder
Face Development
One of the ultimate advantages of the NATM is that complex underground structures can be built without the use of open cut. This is a major consideration when planning the construction of metros or underground rail systems in urban areas.
Conclusion
The success of execution of the NATM is based on three premises: thoughtful, skilful design skilled execution competent supervision and interpretation of observation results
THANK YOU!
Any Question?