As a fundamental study for the development of a blasting technique for the greening of deserts, the detonation velocity of the ANFO, the distribution of the fragment size, and the diffusion amount of nutritional ions were investigated using a 30-cm cubic model of sandstone. Moreover, the behavior was compared with that of granite, which was reported in a previous study. It was observed that the amount of fine fragments increased with an increase in the contact surface area between the ANFO and the sandstone. In comparison with the fragmentation of granite, no significant differences were observed in the particle size of the rock fragments after blasting. The amount of ions in the fragment correlated with the detonation velocity. Thus, the amount of ions for the sandstone, in which a low detonation velocity was observed, was higher than that in the case of granite.
装薬時のANFO周囲の素材強度や込物の程度によって, ANFOの爆ごう挙動, 特に爆速が変化することが知られており, 岩石の物性によって, ANFOを使用した発破による岩石の破砕効果や栄養素イオンの拡散効果が変化する可能性がある。よって, 本研究では, 30 cm立方モデル岩石に直径38 mm, 38 ｍｍ 2ヵ所, 58 mmの発破孔を明けた条件で発破実験を行い, 砂岩と花崗岩での岩石破砕効果および栄養素拡散効果の相違について調査した。その結果, 花崗岩と比較して砂岩中でのANFOの爆速は低く, 破砕効果の低下が予想されたが, 岩石物性により破砕効果に大きな変化は見られなかった。一方, 砂岩粒子中の窒素分含有量は, 花崗岩よりも高かった。
Greening, Desert, ANFO, Fertilization, Blasting method.