Artificial intelligence improving drill+blast processes 26 Nov 2020

Successful drill+blast operations consist of four essential elements: safety, quality, cost and schedule. In order to assist in achieving these operational necessities, Sandvik has continued development of its drill+blast design software iSURE®. The computer program works seamlessly with the Sandvik iSERIES jumbos and associated equipment. The system assures operational efficiency and productivity by producing all the data needed to design and optimise the drill+blast cycle with data collection tools on the rigs and provide accurate analysis functionality. With its user focused features, Sandvik iSURE® has been designed to deliver the best results by capitalizing on the accuracy of the rigs to make drill+blast more accurate and thereby improving work cycles and processes.

Amongst its design attributes, iSURE® 8.0, the latest version of the program, has a wizard-functionality tool that enables the selection of ready-made drilling templates for charge hole plan creation. The template-based plan generation tool takes into account rock blastability, heading profile quality, the allowed excavation damage zone (EDZ) and the explosives being used. Plans created, based on these templates, are readily editable to incorporate drill+blast feedback while being optimized to suit the prevailing rock conditions. This produces an effectively controlled blast that results in good blasting pull out while restricting the fracture zone and resulting in greater rock strength around the excavated tunnel.

Applying artificial intelligence software and systems for optimizing drill+blast excavation of rock

Knowing what has happened

Key to producing the benefits is the combination of rig accuracy and optimized drill+blast plans. The data collection by the rig and its analysis by iSURE® delivers feedback for process improvement. The system is developed to work in conjunction with Sandvik instrumented iSERIES drill rigs that log the round drilling operation to a detailed level. The on-board computers of all Sandvik drill rigs are able to plot the location of the drill holes as recorded in the pre-programmed drill plan and in the project coordinate systems. The rigs can be navigated accurately, based on the defined heading alignment making it possible to express drilled hole coordinates globally and coordinate with the system and plot as-built. Hole start and end points are also assessed to reveal if the holes that have been drilled according to the drill plan. This computer control also allows action to be taken to correct any discrepancies.

Among the many features that iSURE® adds to the process, is the data logging of 19 different measured-while-drilling parameters at 2cm intervals during the drilling of each drilled hole. The recorded data can be examined on a per hole basis, or as a 3D round view (Fig 1). The data can also be presented as a histogram report of the penetration rates for the applied drilling power and flushing sufficiency or disturbances during drilling, both in general terms and for each boom.

Other functional and operational features that are collected for each round and boom include measures for percussion, power pack, drilled meters and net penetration, as well as average and gross drilling capacity. This provides valuable feedback that helps to fine-tune the rig behaviour and use. The program further assists in the analysis of data collected along the heading progress to build a trend of various key performance indicators.

After hole drilling is completed and the holes are charged and blasted, iSURE® has the ability to compare consecutive rounds to calculate the achieved pull out in different areas of the face. This information, as a form of a heat map, can then be superimposed on top of the drilling plan of the heading to indicate where to improve the plan for pull out. No extra parameters need to be measured to provide this information as functionality is based on recording the realised start and end points of each charge hole in the face. Using the drill holes more efficiently to achieve a good pull out results in savings both in excavation schedule and project cost.

Vibration, profile and geological analysis

Through its data recording and analysis abilities, the iSURE system can utilise measured vibration data in order to more accurately control the blasting generated vibrations within defined limits for monitoring environmental limitation factors including vibration and the impact of drill+blast excavations on nearby structures in an urban environment. Based on systematic vibration measurement data and permitted peak particle velocity information, analysis feedback can be used to adjust and define the charges, detonation control and location of the holes in the drill plan to meet project permits as necessary. With control of the blasting process to meet necessary vibration restrictions, more tunnel meters/day can be achieved, as shortening the round length or reducing the face into partial blastings might be avoided.

iSURE® software turns recorded data of measured-while-drilling parameters into graphical 3D and histogram information for improving the drill+blast process as a whole

iSURE® further provides an interface to import vibration data from third party systems and enable the utilisation of this data in connection with momentary design. This facilitates the pinpointing of any holes that generated excessive vibration. For detonation design, iSURE® supports impulse detonator timings of different manufacturers as well as impulse detonators supplemented by surface delay units to increase the usage possibilities of detonators, and free timing settings for electronic detonators.

In an extension of the iSURE® system, drill rigs can be equipped with on board profile scanners to provide an optional toolset for geological analysis and a tunnel profile 3D scanning system. Based on the data generated by iSURE 3D SCAN, the iSURE® 8.0 can create a 3D view visualisation of under and overbreak and a 2D view for drill+blast design optimization, together with volume calculation of realized and theoretical profile under and overbreak. With these details, the drilling rig operator is assisted in drilling additional holes in the correct locations to remove any existing underbreak if it exists.

For further assistance of the drill+blast operations, iSERIES drill rigs can be equipped with the optional iSURE GEO system, which decodes geological parameters based on hole drilling data. Drilling resistance factors for example will measure MPa rock strength, as well as indicators of rock mass fracture and assessment of rock classification. The GEO option used by iSURE® 8.0 enables the viewing and extrapolation of this data in 2D and 3D views. The system is designed as a geological toolbox acting as a complementary subsystem to assist geologists in their daily work through providing a key source of information.

Accurate plans, controlled blasting and immediate analysis and feedback on the rock conditions will lead to increased pull out of estimates up to 97%, based on the proper use of iSURE and iSERIES drill rigs. With optimum blasting control, scaling time might also be reduced by up to 45 min/round. An optimum pull out also creates a better face for the next round of drilling, a reduced damage zone from the subsequent blast, as well as producing a better environment for rock bolting, and the automated production of drilling plans while ensuring that there are fewer interruptions in the operation.

Operators dashboard in the cab of a modern iSERIES drill rig

Empowering the process

In effect, the information provided by iSURE® will also indicate if rig adjustment is needed or if rig misuse is suspected. It shows the change in rock mass drillability, records drill steel consumption, maps face shape after blasting and scaling, operator deviation from the plan while drilling, and, based on scanner data, defines the profile and calculates production volume. All is available at the fingertips of rig operators and operation designers, resulting in improved production and information that can be assessed and built upon to empower the drill+blast process.

Any software is only as good as the drill rig it serves and based on customer focused feedback, iSURE® capabilities on the advanced Sandvik iSERIES rigs constitute a powerful tool that enables the sharing of project data between different group members to achieve the best drill+blast operation possible. iSURE® 8.0 software is available in four versions: Basic, Plus, Premium and Pro to meet the objectives and aims of drill+blast contractors and their contract clients.

Improvement and development of the iSURE® artificial technology system is continually progressing in Sandvik. Updated versions of the software packages are planned annually based on knowledge and experience sharing with customers and drill+blast professionals globally. The next step will be iSURE 8.1 focusing on more data driven productivity to provide customers with extended production reports to optimize the drill+blast cycle and covering the whole fleet of face drilling rigs. The upgraded iSURE 8.1 systems are to be available to the marketplace in January 2021.