Utilizing Robotic Technologies and a Computerized Managed Software Framework to Improve Drill and Blast Tunnel Efficiency

New Austrian Tunnelling Method (NATM), which first appeared in English publications in 1964. NATM was described as a modern tunnelling method by Rabcewicz.

High-performance drill and blast tunnel design approaches necessitate optimizing and considering the different working components that make up the construction phase as a series of sequential and simultaneous operations. The benefit of combining the logistic backup systems is that it allows for better efficiency. Drilling, explosive packing, temporary ground support installation—rock bolts, steel wire, shotcrete, steel sets, lagging, mucking, and logistics—all need to be improved to maximize demand. Better blasting techniques, partial robotization, and device and process integration are also expected.

 Tunneling, especially tunnel excavation by tunnel boring machines, is a common practice. In the last three decades, the number of TBMs has grown. As a result, when a project is being evaluated, drill and blast tunneling is in direct competition with TBM tunneling in terms of cost.

 Drilling and blasting vs. Tunnel Boring Machine Excavation

 In addition to geology, project-specific considerations such as tunnel length and cross-section have a major effect on tunnelling tool selection. For mechanized rock tunnel drilling, gripper TBMs or shield and telescopic shield TBMs are currently used. The ‘‘backup" plant provides ventilation, compressed air, water, discharge piping, electrical transformers, electricity, and motor control centers for the logistics facility, as well as serving as a distribution point for material storage, temporary ground assistance, and muck. For material supply and muck disposal, a choice is made between conveyor belt, train, or rubber-tired vehicles, depending on the size/cross-section of the tunnel.

 The phase length and operating continuity are the key differences between traditional mechanized drill and blast and TBM tunneling. A specified tunnel diameter is required for a TBM drive. The TBM can excavate such a circular profile with a high degree of precision. The tunnel cross-section can be formed to any desired form using drill and blast methods, and the tunnel shape can be varied along the length of the drive.

Where possible, the diameter of a circular cross-section can be increased or reduced, or the circular cross-section can be modified to a horseshoe shape. However, in the worst-case drill-and-blast situation, blasting over break of 10–25 per cent of the plan cross-sectional region will occur. This content would need to be discarded, and the room will need to be refilled. Drill and blast excavations necessitate much more temporary ground support activity at the face and in the excavation area than TBM excavations. In certain cases, a shield TBM is the only feasible tunneling alternative. When all TBM and drill and blast approaches are viable, the risks must be carefully evaluated by carefully assessing the positive and negative factors, particularly in terms of the risks and costs that could occur if unintended or unforeseen geological circumstances arise. Tunneling is a high-risk operation, and the number and magnitude of injuries are similar to both processes.

 Drill and Blast Tunneling Mechanization

 How will drill and blast tunneling compete more effectively with the TBM method? First, stability is needed in the face of changes in the excavated cross-section shape and scale, as well as the construction of different types of temporary rock support. However, there are two fields where there is a need for development.

 1.       The heading area, which includes the cyclic production operations of heading drill, blast, excavation, muck loading, and primary temporary support installation.

2.       The back area, which includes all heading excavation operational support services and final ground support work, including the simultaneous movement of support infrastructure that may follow the excavation/heading process, and separators.

 Drill and blast tunneling can be made more efficient and cost-effective by using mechanized technologies. This will require the use of highly advanced, robotic, and specialized equipment in the excavation/heading area, as well as increased mechanization of the continuous movement of all support infrastructure facilities in the back area. The drill and blast tunneling cycle's current mode of operation is to drive each support facility forward independently, following the heading. What is needed is a manufacturing cycle that allows for parallel transportation and work processes.

This can be accomplished by dividing storage and working areas in the back of the heading in a predefined format and carefully organizing transport flows. Furthermore, by reducing hard manual labor and improving air quality, it is possible to improve working conditions.

Land support procedures and the work procedure for installing the final tunnel lining should be isolated while a suspended platform is required.

1                    The facilities, initial phase of muck flow away from the header, air supply ducts, and services are all situated in the top area.

2                     The bottom section, which includes equipment parking and storage, invert construction, material handling for supply ground support, explosives, and the loading of muck into the tunnel transport system at the end furthest from the header.

 Blast Technology

Tunnel blasting technology is affected by three factors:

1.       safe handling of explosives reduction of the possibility of an unintended detonation

2.       Post-blast gases, nitrous oxides, and carbon monoxide toxicity are minimized.

3.       Boreholes can be loaded and charged quickly and easily.

 Innovation

Field experiments and implementation are used to test and improve drill and blast tunneling innovations. In parallel with the mechanization of drill and blast processes, the following system innovations should be followed.:

1.       Use of robotic devices for explosives loading

2.       Use of robotic devices for shotcrete placement

3.     Use of JUMO

 Conclusion

 Owing to the use of cyclical high-performance equipment and a suspended platform, performance can be improved by about 30percent.

1.       Working man-hours in the heading sector will be lowered by around 30% in a row, lowering operating costs.

2.       Protection can be strengthened by splitting the transportation processes from the working and machinery service areas, and advancement can be achieved by eliminating heavy manual labor.

3.       Management must be persuaded to support the use of robotics and computer-directed devices to replace historically manual labor, and managing the increasingly advanced machines employed in cyclic processes necessitates a highly skilled staff. The labor force's and site managers' skills must be improved. Innovative, specialized, and computer-controlled technology has laid the foundation for the industrialization of drill and blast tunneling. It is necessary to speed up the erection and installation of rock support systems, especially in arch construction. In the heading and facilities fields, it is important to maximize the number of simultaneous operations.

Greater transparency at the bidding stage can be provided in future tunnel projects so that responsible contractors can align the necessary temporary ground support needs with the configuration of the services/backup systems. Tunnel excavation is made easier and more cost-effective by planning engineers and responsible contractors work together as a team.

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