A diverse array of new tunnelling technologies will help boost productivity and cut project costs, while boosting quality - Mike Woof writes
The worldwide market for tunnelling projects continues to be strong, with a series of major projects underway or planned for the future. These good market conditions have helped fuel research and development in new tunnelling equipment, designed to be more productive, more efficient and more reliable and able to deliver a higher quality of work.
Drilling and blas
Sandvik claims its new drilling rig offers versatilitya and high performance
A diverse array of new tunnelling technologies will help boost productivity and cut project costs, while boosting quality - Mike Woof writes
The worldwide market for tunnelling projects continues to be strong, with a series of major projects underway or planned for the future. These good market conditions have helped fuel research and development in new tunnelling equipment, designed to be more productive, more efficient and more reliable and able to deliver a higher quality of work.
Drilling and blasting remains one of the most important tunnelling methods, with technology from Northern Europe dominating this market segment. One of the main competitors,325 Sandvik, is rolling out new drilling hardware in the shape of its sophisticated and powerful DT922i tunnelling jumbo, which is also said to be productive and versatile. The machine is fully automated and runs on a new articulated carrier, fitted with a new cabin that has 25% more visibility than previous designs, as well as low working noise.
A key feature of this rig is its highly sophisticated control system, which combines with Sandvik’s iSURE excavation management tool to deliver high working efficiency. This technology allows the driller to work from a pre-designed blasting pattern so as to achieve high-quality results with minimum over, or under breaking. The machine is said to be designed to deliver improved tunnel quality and can excavate cross-sections of up to 125m², with capabilities including face drilling, bolt hole drilling, and long-hole drilling.
The firm claimed that the rig offers the same intelligence as its other i-series jumbos, coupled with the extra versatility of the new carrier and improved automation. The articulated carrier allows the jumbo to operate in tight tunnels with narrow corners while the cab raising system provides visibility for working while allowing the machine to be driven through restricted height tunnel sections. Its hydrostatic transmission and joystick controls provide precise dynamic control of tramming speed and steering. It has a multi voltage concept that allows for different electric voltages and allows easy and fast shifts to different worksites.
The amplified drilling automation helps to deliver accurate blasting results. The machine is equipped with the Sandvik Intelligent Control System Architecture (SICA), a proven drilling system with nine different hole type settings. It also offers three alternative control methods: manual drilling control, feed percussion follow-up, and intelligent torque control. Another feature of the DT922i is its boom control system with three different modes for manual boom control.
The Sandvik RD525 rock drill meanwhile is said to provide 17% higher penetration rates, 40% longer life for the shank, as well as 17% longer bit life compared to its predecessor. The twin SB100i booms feature a stiff square profile, boosting support to the rock drills and further adding to drilling precision.
The 30tonne machine can handle hole lengths of up to 5.88m, has a transport height of 3.19m, a transport width of 2.5m and a drilling width of 3.5m. Customers have the choice of a Tier 3 compliant diesel rated at 119kW or a Tier 4Final compliant diesel delivering 122kW, while the powerpack consists of two 75kW IE3 compliant electric motors.
Two automation levels are also offered: gold and platinum. The standard gold package facilitates drilling according to predefined drill plans. This automation level includes features such as drilling to predefined depth, drill plan visualisation, rig navigation and an option for automatic long-hole drilling. It also integrates the iSURE tunnel management tool to generate accurate plans for drilling, charging and blasting, as well as a data collection and analysis tool for improving work cycle and process. The platinum package includes all features from the gold system, but with the added benefit of full automatic face drilling.
Sandvik is also introducing an advanced tunnelling drill-rig instrumentation package. Coupled with existing drill-and-blast design and control systems, this is said to deliver higher levels of accuracy for standard jumbos. The TCAD+ system can be specified as an option for all Sandvik DT tunnelling rigs, and can be retrofitted to many other models, providing the boom joints have sufficient space for sensors. It succeeds the TCAD system with additional features.
The TCAD+ system offers improved accuracy when using pre-designed drilling plans in combination with automated drilling. It can work with the iSURE software for more accurate drill pattern and blast design according to the planned tunnel dimensions of excavation.
Blasthole pattern accuracy is improved by TCAD+, while increased accuracy can also be delivered for rockbolt pattern formation using the monitoring on the new operator display console. The system can also be used to deliver accurate long-hole as TCAD+ makes it easier to add to the number of drill-rods used without monitoring complications. There is also a wider range of navigation options, including the use of a tripod-mounted total station to provide the reference.
Combining the TCAD+ drill-rig control with the iSURE tunnel excavation design software allows more efficient working for the tunnel line, theoretical profile required, drill plan design and analysis of data collected. The system is able to adjust the hole-bottom spacing and the burdens, as well as analysing the charges and blast-induced rock cracking. The system is said to deliver optimum accuracy and achieve cost savings as a result.
A record of drilling performance is collected for processing by iSURE and also during operation. Once drilling is in progress the new display screen offers an indication for the drilling status of the drill on each boom. Standard data collected includes the geometrical positions of the drilled holes, rate of drilling penetration and other standard values, including percussion pressure, feed pressure, rotation speed and incoming hole flushing water pressure.
Actual savings depend on the specific site conditions but, based on field experience, Sandvik believes that the system offers about 5% better pullout using iSURE. This is equivalent to 12 fewer rounds/km of tunnel, with significant savings for time, energy and explosives. As regards profile accuracy, for a tunnel section of 8x8.57m, the system reduces overbreak by about 150mm less overbreak, a reduction in rock excavation of 4,350m3/km of tunnel and delivering substantial savings through reduced spoil haulage.
Using excavators fitted with hydraulic breakers or scarifying tools is another proven tunnelling method and German firm718 Liebherr is offering a new model for this market in the shape of its R950 tunnel excavator. Compact in design, the machine is said to be well suited for use in underground applications and can deliver high productivity as well as safety for the operator. The new 45tonne machine is powered by a Tier 4 Final-compliant Liebherr diesel delivering 150kW, with an optional 190kW version also available. The machine can work in tunnels with heights from 5m to 8m and replaces the earlier R944 C Tunnel model. A new height adjustment feature automatically stops the movement of the excavator to avoid impact with the surroundings, while its short tailswing and rear-view cameras further reduce the risk of damage against the tunnel walls.
Smart systems for Portuguese tunnel
Texeira Duarte has awarded5264 Indra a contract for intelligent traffic systems for the Marao tunnel. Currently under construction, the 6km tunnel will be the longest in Portugal and the Iberian Peninsula when it is complete. Indra is kitting out the Marao tunnel control centre with its proprietary Horus traffic and tunnel management solution. Indra will implement automatic incident detection and video surveillance systems using closed-circuit television (CCTV), signalling systems, fire detection, communication, a public address system, SOS posts, and loading gauges and dangerous goods controls.
The advanced video surveillance system with automatic incident detection will use artificial vision to enable an immediate response to potentially dangerous events. The Indra solution is also integrating an innovative control system for dangerous goods using video surveillance and a licence plate recognition system based on algorithms.Productivity and versatility are said to be optimised due to the range of attachments available, including buckets, breakers, scarifiers and drills, with a quick coupler unit allowing fast changes between work tools. Breakout forces have been increased compared to the previous model, while revised hydraulics increase the hydraulic power available for attachments.
Customers can specify either the open cab without windscreen or side glass, or a fully enclosed unit, although both are protected by integral roll-over protective structure (ROPS) structures and feature rear and lateral cameras to boost visibility for the operator.
Once the material has been excavated it has to be removed, and161 Atlas Copco has developed a new package for selecting the optimum loading option for each operation. This novel digital tool is called the Loading Optimiser and can be used to select solutions that match conditions at the worksite.
The package offers an alternative to the trial-and-error approach to spoil removal in which different solutions are tried at a worksite until the most suitable is found. This new digital tool allows various methods and types of equipment to be evaluated in relation to key parameters from the worksite. The system then identifies the most suitable option.
The tool is able to process a large number of variables that can be altered and fine-tuned multiple times. Key factors such as methods, equipment specifications, the type of ventilation system, and other factors can be evaluated in a variety of ways. The system enables the user to see the impact of these variations on efficiency, productivity and costs.
One of the most crucial parameters is the ventilation arrangement. The dimensions of a tunnel or drift, the space required in the roof for ducting and the area that is left for equipment is not an easy equation. The firm said that the tool can synchronise the data with its Serpent ventilation system and also simulate alternative solutions on screen.
Other benefits of the tool include the possibility to evaluate selected method/equipment options and produce complete overviews of costs as well as customised spreadsheets of the selected solution.
The worldwide market for tunnelling projects continues to be strong, with a series of major projects underway or planned for the future. These good market conditions have helped fuel research and development in new tunnelling equipment, designed to be more productive, more efficient and more reliable and able to deliver a higher quality of work.
Drilling and blasting remains one of the most important tunnelling methods, with technology from Northern Europe dominating this market segment. One of the main competitors,
A key feature of this rig is its highly sophisticated control system, which combines with Sandvik’s iSURE excavation management tool to deliver high working efficiency. This technology allows the driller to work from a pre-designed blasting pattern so as to achieve high-quality results with minimum over, or under breaking. The machine is said to be designed to deliver improved tunnel quality and can excavate cross-sections of up to 125m², with capabilities including face drilling, bolt hole drilling, and long-hole drilling.
The firm claimed that the rig offers the same intelligence as its other i-series jumbos, coupled with the extra versatility of the new carrier and improved automation. The articulated carrier allows the jumbo to operate in tight tunnels with narrow corners while the cab raising system provides visibility for working while allowing the machine to be driven through restricted height tunnel sections. Its hydrostatic transmission and joystick controls provide precise dynamic control of tramming speed and steering. It has a multi voltage concept that allows for different electric voltages and allows easy and fast shifts to different worksites.
The amplified drilling automation helps to deliver accurate blasting results. The machine is equipped with the Sandvik Intelligent Control System Architecture (SICA), a proven drilling system with nine different hole type settings. It also offers three alternative control methods: manual drilling control, feed percussion follow-up, and intelligent torque control. Another feature of the DT922i is its boom control system with three different modes for manual boom control.
The Sandvik RD525 rock drill meanwhile is said to provide 17% higher penetration rates, 40% longer life for the shank, as well as 17% longer bit life compared to its predecessor. The twin SB100i booms feature a stiff square profile, boosting support to the rock drills and further adding to drilling precision.
The 30tonne machine can handle hole lengths of up to 5.88m, has a transport height of 3.19m, a transport width of 2.5m and a drilling width of 3.5m. Customers have the choice of a Tier 3 compliant diesel rated at 119kW or a Tier 4Final compliant diesel delivering 122kW, while the powerpack consists of two 75kW IE3 compliant electric motors.
Two automation levels are also offered: gold and platinum. The standard gold package facilitates drilling according to predefined drill plans. This automation level includes features such as drilling to predefined depth, drill plan visualisation, rig navigation and an option for automatic long-hole drilling. It also integrates the iSURE tunnel management tool to generate accurate plans for drilling, charging and blasting, as well as a data collection and analysis tool for improving work cycle and process. The platinum package includes all features from the gold system, but with the added benefit of full automatic face drilling.
Sandvik is also introducing an advanced tunnelling drill-rig instrumentation package. Coupled with existing drill-and-blast design and control systems, this is said to deliver higher levels of accuracy for standard jumbos. The TCAD+ system can be specified as an option for all Sandvik DT tunnelling rigs, and can be retrofitted to many other models, providing the boom joints have sufficient space for sensors. It succeeds the TCAD system with additional features.
The TCAD+ system offers improved accuracy when using pre-designed drilling plans in combination with automated drilling. It can work with the iSURE software for more accurate drill pattern and blast design according to the planned tunnel dimensions of excavation.
Blasthole pattern accuracy is improved by TCAD+, while increased accuracy can also be delivered for rockbolt pattern formation using the monitoring on the new operator display console. The system can also be used to deliver accurate long-hole as TCAD+ makes it easier to add to the number of drill-rods used without monitoring complications. There is also a wider range of navigation options, including the use of a tripod-mounted total station to provide the reference.
Combining the TCAD+ drill-rig control with the iSURE tunnel excavation design software allows more efficient working for the tunnel line, theoretical profile required, drill plan design and analysis of data collected. The system is able to adjust the hole-bottom spacing and the burdens, as well as analysing the charges and blast-induced rock cracking. The system is said to deliver optimum accuracy and achieve cost savings as a result.
A record of drilling performance is collected for processing by iSURE and also during operation. Once drilling is in progress the new display screen offers an indication for the drilling status of the drill on each boom. Standard data collected includes the geometrical positions of the drilled holes, rate of drilling penetration and other standard values, including percussion pressure, feed pressure, rotation speed and incoming hole flushing water pressure.
Actual savings depend on the specific site conditions but, based on field experience, Sandvik believes that the system offers about 5% better pullout using iSURE. This is equivalent to 12 fewer rounds/km of tunnel, with significant savings for time, energy and explosives. As regards profile accuracy, for a tunnel section of 8x8.57m, the system reduces overbreak by about 150mm less overbreak, a reduction in rock excavation of 4,350m3/km of tunnel and delivering substantial savings through reduced spoil haulage.
Using excavators fitted with hydraulic breakers or scarifying tools is another proven tunnelling method and German firm
Smart systems for Portuguese tunnel
Texeira Duarte has awarded
The advanced video surveillance system with automatic incident detection will use artificial vision to enable an immediate response to potentially dangerous events. The Indra solution is also integrating an innovative control system for dangerous goods using video surveillance and a licence plate recognition system based on algorithms.Productivity and versatility are said to be optimised due to the range of attachments available, including buckets, breakers, scarifiers and drills, with a quick coupler unit allowing fast changes between work tools. Breakout forces have been increased compared to the previous model, while revised hydraulics increase the hydraulic power available for attachments.
Customers can specify either the open cab without windscreen or side glass, or a fully enclosed unit, although both are protected by integral roll-over protective structure (ROPS) structures and feature rear and lateral cameras to boost visibility for the operator.
Once the material has been excavated it has to be removed, and
The package offers an alternative to the trial-and-error approach to spoil removal in which different solutions are tried at a worksite until the most suitable is found. This new digital tool allows various methods and types of equipment to be evaluated in relation to key parameters from the worksite. The system then identifies the most suitable option.
The tool is able to process a large number of variables that can be altered and fine-tuned multiple times. Key factors such as methods, equipment specifications, the type of ventilation system, and other factors can be evaluated in a variety of ways. The system enables the user to see the impact of these variations on efficiency, productivity and costs.
One of the most crucial parameters is the ventilation arrangement. The dimensions of a tunnel or drift, the space required in the roof for ducting and the area that is left for equipment is not an easy equation. The firm said that the tool can synchronise the data with its Serpent ventilation system and also simulate alternative solutions on screen.
Other benefits of the tool include the possibility to evaluate selected method/equipment options and produce complete overviews of costs as well as customised spreadsheets of the selected solution.
