Question 1

What is C-TUNNEL?

Accepted Answer

C-TUNNEL is a software tool dedicated to the pre-design ('draft') stage of tunnel projects. Built on the CESAR-LCPC finite-element kernel, it lets engineers produce quick 2D pre-design analyses and reports, primarily through the convergence-confinement method.

Question 2

Who develops C-TUNNEL?

Accepted Answer

C-TUNNEL is developed by itech (itech-soft.com), the company behind the CESAR-LCPC finite-element suite. CESAR-LCPC's numerical core originates from LCPC / IFSTTAR (now Université Gustave Eiffel), and C-TUNNEL was developed in collaboration with CETU, the French national tunnel research centre.

Question 3

Is C-TUNNEL the same as CESAR-LCPC?

Accepted Answer

No. C-TUNNEL is a dedicated tunnel pre-design tool that runs on the CESAR-LCPC kernel. CESAR-LCPC (CESAR 2D/3D) is the full finite-element platform for geotechnical, tunnel and civil engineering analysis; C-TUNNEL is focused on quick draft-stage tunnel work and can export its models into CESAR 2D for detailed analysis.

Question 4

What analysis method does C-TUNNEL use?

Accepted Answer

Its central method is the convergence-confinement (ground-reaction) approach, presented in a parametric and didactic way, supported by 2D finite-element computation from the CESAR-LCPC kernel.

Question 5

Is C-TUNNEL a detailed design tool or a pre-design tool?

Accepted Answer

C-TUNNEL is explicitly positioned as a pre-design / 'draft' project tool. It is intended for quick conceptual and feasibility assessment; for detailed finite-element analysis the project is exported to CESAR 2D.

Question 6

Can I move a C-TUNNEL model into CESAR for more detailed analysis?

Accepted Answer

Yes. Models built in C-TUNNEL can be exported to CESAR 2D, where the project can be extended with more complex geometry, staging and material behaviour for full finite-element analysis.

Question 7

Does C-TUNNEL support parametric studies?

Accepted Answer

Yes. Parametric study capability is built in, so engineers can vary key inputs and quickly understand the sensitivities and boundaries of a tunnel project during pre-design.

Question 8

Does C-TUNNEL design tunnel lining reinforcement or check it against a design code?

Accepted Answer

No. C-TUNNEL is a finite-element pre-design and analysis tool centred on ground-support interaction; it is not marketed as a code-based reinforced-concrete lining design tool. Engineers carry out code-based lining and reinforcement design separately, using the forces from the analysis as input.

Question 9

Is C-TUNNEL suitable for TBM / segmental lining design?

Accepted Answer

C-TUNNEL itself is focused on convergence-confinement pre-design of conventionally excavated tunnels. The broader CESAR-LCPC suite provides dedicated tools for modelling tunnel boring machine (TBM) excavation and lining; for TBM and segmental-lining work, CESAR 2D/3D rather than C-TUNNEL is the relevant tool.

Question 10

Who typically uses C-TUNNEL?

Accepted Answer

It is used by tunnel and geotechnical engineers for conceptual and feasibility-stage tunnel assessment, and it is also valuable for teaching and training because the convergence-confinement method is presented in a clear, parametric way.

Question 11

What kind of output does C-TUNNEL produce?

Accepted Answer

It produces quick pre-design reports for tunnel projects, based on the convergence-confinement analysis and any parametric studies the engineer has run.

Question 12

Is C-TUNNEL available in India through RAM CADDSYS?

Accepted Answer

Yes. RAM CADDSYS is the authorized distributor in India for the CESAR-LCPC suite, including C-TUNNEL, providing licensing, training and technical support for tunnel and geotechnical engineering teams.

Criterion	C-TUNNEL	CESAR 2D
Project stage	C-TUNNELPre-design / "draft" stage — fast conceptual and feasibility screening	CESAR 2DDetailed finite-element analysis once the concept is set
Analysis method	Convergence-confinement (ground-reaction) method, presented in a parametric, didactic form	Full 2D finite-element modelling with more complex geometry, staging and constitutive behaviour
Scope	Circular and non-circular cross-sections for conventionally excavated (NATM) tunnels, with built-in parametric studies	Broader tunnel and geotechnical finite-element analysis, including TBM excavation and segmental lining modelling
Typical output	Quick pre-design reports for early decision-making	Detailed finite-element results for design development and verification

C-TUNNEL-TunnelLiningDesignSoftware

What is C-TUNNEL?

Where C-TUNNEL works

Tunnel feasibility and concept studies

Parametric sensitivity assessment

Pre-design hand-off to detailed FE analysis

Teaching and training in ground-support interaction

BIM Integration

CESAR 2D / CESAR-LCPC suite

C-TUNNEL vs CESAR 2D

Looking for C-TUNNEL Training?

License Types

Perpetual License

Subscription License

Frequently Asked Questions

Put C-TUNNEL to work
on your next project.

C-TUNNEL-TunnelLiningDesignSoftware

What is C-TUNNEL?

Where C-TUNNEL works

Tunnel feasibility and concept studies

Parametric sensitivity assessment

Pre-design hand-off to detailed FE analysis

Teaching and training in ground-support interaction

BIM Integration

CESAR 2D / CESAR-LCPC suite

C-TUNNEL vs CESAR 2D

Looking for C-TUNNEL Training?

License Types

Perpetual License

Subscription License

Frequently Asked Questions

Put C-TUNNEL to workon your next project.

Put C-TUNNEL to work
on your next project.