What Is Tunnel Design Construction Process?
Tunnels are underground passages, mainly used to transport public, freight, sewage and water. Since there is a lot of involvement in various materials like rocks, stones, and soil, tunnel construction requires the combined skills of different engineering fields like mining, civil, geology, and electrical engineering. 

Advantages of the tunnel

1] Non-intrusive: During the construction of tunnels, it will not disturb any of the surface activities like stopping vehicle traffic or any other recreational activities. 
2] Cost-effective: Tunnels can be less expensive than bridges or open vertical earthwork cuttings while transporting public utility services like wastewater, gasoline, and similar highway projects. 
3] Stability: Proper quality material must be used in the construction of tunnels. Top civil engineering firms consider several geological factors 
such as construction sequencing, ground and sub-ground conditions, construction time, construction cost, etc., while deciding the feasibility of a tunnel project.

What is tunnel design?
The building of tunnels has increased extensively in seismic zones where there is a high risk of landslides. Construction of tunnels in such areas is a dangerous and complicated process because of the surface subsidence, deformed support system, instability of the tunnel face, and failure in the tunnel portal. The top civil engineering companies examine the conduct of the underground structure from the start, bypassing geological, topographical, and environmental limitations of the designed project by the design and construction of tunnels process. The process has a few steps

1] The civil engineering company will first look for suitable ground conditions 
2] They will test the engineering parameters and then plan a tunnel excavation method. 
3] They will create liner design parameters, evaluate surface settlements, and finally cover their impacts on adjoining facilities.
4] They will also study the completed projects to formulate the risks and mitigation strategies. 

Tunnel shafts are vertical courses that combine the ground surface with the tunnel roof. Shafts have many benefits in creating tunnels. It is essential to ensure the position and course of the tunnel correctly align and set out on the surface. The engineers design the shafts at defined points on the tunnel line to assist underground operations.

Tunnel shaft design and shapes
1] Inclined shafts
Inclined shafts are designed for shafts with less depth. The excavation of such shafts is done from the top, which means your excavated material will fall into the tunnel from where you must remove it.
2] Vertical Shafts
Vertical shafts are simpler and easier to excavate than inclined shafts. Here, a pilot shaft is first driven upward before the shaft is excavated to the entire section in the downward direction. Then, they use the pilot shaft to remove the dirt and debris out.
3] Circular Shafts
These shafts are usually roundish and have a pre-stressed steel liner plate or concrete. 

Conclusion:
For such important projects, you must choose a reputed and experienced engineering firm to work for you. It is one way to find a permanent partner to work on your future projects and build a healthy and long-lasting relationship. If you have a project coming up, ensure you choose the correct civil engineering firm to complete.