TBM Mud system
TBM mud system has a good effect on the mud produced in the shield construction. TBM slurry separation system is the module system structure. The TBM mud system is designed to handle the various mud used in common shield construction techniques.
TBM mud system and drilling and blasting are being used for construction of tunnels. Drilling and blasting uses various explosives or gas pressure blasting for breaking the rock to be excavated. Before the practice of TBM system separation use drilling and blasting was the most economical ways to make tunnels through hard rocks. Even till date drilling is practiced in some places.
The decision as to which mechanism for making tunnel is to be used depends on the length of the tunnel. Cost of TBMs is high but due to their fast rate of penetration and less man power necessity, per meter cost in long tunnel is comparatively very less. Even the condition of ground has to be taken into consideration as to which mechanism is to be used.
Tunnel boring machine separation have several advantages over drilling and blasting as–
– Excavation speed – Main advantage of TBMs is its speed. Their speed though depends on various factor is up to 100-150 meters per day in favorable conditions. In Norway these had reportedly excavated the rate of 300 meters in very extreme conditions.
– Ventilation is better in the tunnels made
– Its circular profile helps long term stability
– Safety of workers is assured; at first within the tunnel boring machine separation and later by traditional support mechanisms
– Improved working conditions for workers- highly mechanized tunnel boring machine separation help the worker thus less intensive work has to be performed by them.
– Simplified disposal- as the cutting are of similar sizes, their disposal to the surface is much easier.
Due to this tunnel boring machine separation are cost effective and efficient in long drive tunnels with straight opening underground for workers. They cost one third of the cost of drilling and blasting and greatly decreased construction time.