Tunnels
CESAR is a calculation software enabling modelling and analysis of geotechnical problems. Proven, powerful and user-friendly, it covers a wide scope of soil and rock mechanics applications (deformation, stability...). It is a valuable tool for geotechnical engineers for embankment, excavation, foundation or tunnel studies, and more.
Conventional method
The user will easily produce tunnel design projects by the Conventional Method (or New Austrian Tunneling Method, NATM, or Sequential Excavation Method, SEM). The complete set of CAD tools in CESAR 2D and CESAR 3D allows unlimited types of sketches of the tunnel. The detailed sequence of ground excavation and the activation of the structural components of the final project (shotcrete, final lining and station infrastructure) can be modelled using specific and intuitive tools (excavation forces, long-term effects on the concrete…).
Design of a tunnel section with NATM
Vertical displacements induced by 3D tunnelling in urban area
Tunnel boring machine
CESAR (2D and 3D) is bundled with the required tools for modelling the complex sequence of the tunnel boring machine excavation.- Pressure at the front,
- Controlled excavation forces for TBM shield conicity,
- Variable pressure for the radial grouting,
- Modelling of the lining segments with shell or volume elements.
Modelling of the TBM excavation process
Bi-tube tunnel (vertical displacements)
Cut-and-cover method
This method is declined in Conventional Bottom-Up Construction or in Top-Down Construction. CESAR 2D and CESAR 3D provides the tools and analysis components for the accurate modelling of the construction stages: retaining walls, struts, the various slabs and final backfill. With structural elements (beams and bars, shells) and adapted interface elements (joints), the tunnel engineer will analyse properly the soil-structure interaction.
Cut-and-cover construction of a metro station
Covered trench analysis
Ground supports
In poor ground conditions or in urban projects, the design of the tunnel requires the soils reinforcement in order to reduce the settlements. CESAR is equipped with a full set of elements (1D beams and bars) for the modelling of radial or front bolts, or pipe umbrellas. User can also use specific elements with friction law for a sharp modelling of the soil-reinforcement behaviour.
Bolted tunnel
Pipe umbrella and front reinforcement
