NMR-based investigation on deterioration characterization of gypsum breccia in surrounding rock undergoing flow-by wetting-drying cycles. Issue 7 (October 2021)

• Record Type: Journal Article
• Authors: Jiang, Song; Peng, Yixin; Lu, Yao; Huang, Ming
• Is Part Of: IOP conference series. Volume 861:Issue 7(2021)
• Publication Date: 2021-10
• Subjects: Gypsum breccia -- Water flow -- Wetting-drying cycles -- NMR; Earth sciences -- Periodicals; Environmental sciences -- Congresses; Environmental sciences -- Periodicals; 550.5
• DOI: 10.1088/1755-1315/861/7/072102
• Languages: English
• ISSNs: 1755-1307

Abstract

Abstract: In underground engineering, many geological hazards caused by the cyclic actions of wetting and drying occur under flowing water conditions. Understanding the evolution of the strength and pore structure characteristics of some environmentally sensitive surrounding rocks under these conditions is critical for maintaining the long-term stability of tunnels. In this study, the deterioration characteristics of gypsum breccia in the surrounding rock of an anonymous tunnel in Shanxi under the flow-by wetting-drying cycles were investigated. After being treated by wetting-drying cycles with different flow conditions (0 and 10 l/h), the evolution characteristics of the pore structure of gypsum breccia were characterized using the nuclear magnetic resonance (NMR) technique. The relationship between the P-wave velocities and the pore characteristics of gypsum breccia was studied. The results showed that the water flow would accelerate the deterioration process of gypsum breccia in the wetting-drying process. The microstructure damage of gypsum breccia was induced by the combined action of the wetting-drying cycles and water flow. There was a significant correlation between the attenuation of P-wave velocity and the development of the pore structure of gypsum breccia. The study can provide references for the engineering design of tunnels in gypsum breccia.