Air decking is nothing but creating an empty space in a blast hole. The location of the air deck could be at the bottom, middle or top of the charge column. Depending on the surrounding rock conditions, a solid or water deck may also be positioned in a blast hole to decrease the explosive charge (Monjezi et al., 2023).
In order to maximise fragmentation and minimise certain charges and blast nuisances, an air deck uses one or more airborne gaps inside a column charge. The blasting industry has seen significant changes as a result of the use of this method. Since its inception in 1891, this approach has been beneficial.
An air deck can be positioned at bottom, middle or above the column charge inside the blasthole. (Saqib et al., 2016) conducted several explosive tests on concrete blocks and created small-scale simulations of actual detonation scenarios. According to his findings, smaller rock fragments are produced when an air deck is inserted in the centre of the charge, but coarser fragments are produced when an air deck is inserted close to the ground or downstream.
(Lu & and Hustrulid, 2003) stated that placing the air deck above the charge column would be more advantageous because the explosive energy could spread into the air deck that would be generated above the column, causing condensed but sustained stress in the blast hole’s collar zone.
Reference
Lu, W., & and Hustrulid, W. (2003). A Further Study on the Mechanism of Airdecking. Fragblast, 7(4), 231–255. https://doi.org/10.1076/frag.7.4.231.23532
Monjezi, M., Amiri, H., Mousavi, M. N. S., Hamidi, J. K., Khandelwal, M., Monjezi, M., Amiri, H., Mousavi, M. N. S., Hamidi, J. K., & Khandelwal, M. (2023). Comparison and application of top and bottom air decks to improve blasting operations. AIMS Geosciences, 9(1), Article geosci-09-01-002. https://doi.org/10.3934/geosci.2023002
Saqib, S., Tariq, S., & Ali, Z. (2016). Improving Rock Fragmentation Using Airdeck Blasting Technique. Pakistan Journal of Engineering and Applied Sciences. https://www.semanticscholar.org/paper/Improving-Rock-Fragmentation-Using-Airdeck-Blasting-Saqib-Tariq/a83e9224852b9025137e04589a9f737ac1e4ee43
