Details

Autor(en) / Beteiligte

• Ding, Rui
• Sun, Qiang
• Geng, Jishi
• Luo, Tao
• Yuan, Shihao

Titel

Porosity and mechanical strength of microwave-heated gabbro

Ist Teil von

• Geomechanics and geophysics for geo-energy and geo-resources., 2022-12, Vol.8 (6), Article 196

Ort / Verlag

Cham: Springer International Publishing

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The efficient fracturing of hard rock is a key factor for exploration and development of deep resource. Microwave induced rock fracture technology is an important tool to achieve continuous mining of hard rock without blasting. In this paper, gabbro was irradiated for different times (0–15 min) in a 0.9 kW microwave environment to investigate the changes in pore and compressive strength using NMR and uniaxial compression tests. The results show that microwave irradiation can be divided into three stages of 0 min, 5–10 min and 12–15 min, and the changes of porosity and compressive strength are closely related to these three stages. The surface temperature, porosity and permeability of gabbro increased and the compressive strength decreased with the increase of microwave irradiation time. This is due to the strong wave absorption of pyroxene and black mica in gabbro, and the uneven thermal expansion of the mineral composition generates thermal stress. The surface cracks of gabbro are dominated by intergranular cracks during the first 10 min of microwave irradiation and then by transgranular cracks. The results of this study are important to promote the future development of microwave-assisted rock-breaking technology. Article highlights λ Porosity and compressive strength of gabbro are closely related to microwave time. λ Increased thermal damage to gabbro by microwave heating compared to traditional heating. λ Pore and fracture evolution affects the compressive strength of gabbro.