Study on plastic zone morphology and elastic strain energy distribution characteristics of surrounding
rock in grouting borehole
Li Hongjiao 1, 2, 3, Li Chen 4, Zhang Wenlong 5
1. Mine materials Branch, CCGTEG China Coal Research Institute, Beijing 100013, China; 2. State Key Laboratory of High Efficient Mining and Clean Utilization of Coal Resources, Beijing 100013, China; 3. National Energy Technology and Equipment Laboratory of Coal Utilization and Emission Control, Beijing 100013, China; 4. Wuhan Engineerring Company CCTEG , Wuhan 430064, China; 5. Qingdao Huanghai University, School of Architectural Engineering, Qingdao 266555, China
Abstract： Underground grouting in coal mine can reinforce the surrounding rock and better ensure the safe production of coal mine. However, there is often no optimization method for the spacing design of grouting boreholes. In this study, by studying the distribution of plastic zone and the distribution characteristics and laws of elastic strain energy around grouting boreholes, an idea of determining the spacing design of grouting boreholes was obtained. The results show that the distribution of the plastic zone can provide a reference for the expansion channel of the slurry. When the shape of the plastic zone determined by the stress condition is butterfly, the interconnection between the butterfly leaves can be used as one of the principles for determining the spacing of grouting holes. The strain energy distribution cloud diagram of elastic-plastic medium is closely related to the distribution of plastic zone. When the pressure is applied to the surrounding rock through the grouting hole, the slurry is expanded along the direction of butterfly leaf with high probability as the channel of energy release. The change law of elastic energy is the same as that of plastic zone. When the butterfly plastic zone is formed, the storage strain energy of elastic-plastic model increases obviously, and the difference of elastic energy between pure elastic model and elastic-plastic model is large. In the design of grouting borehole spacing, the optimal spacing results can be obtained from the perspective of the connection of plastic zone and the release degree of elastic energy. This study provides a new method for determining the spacing of grouting boreholes by plastic zone distribution and elastic strain energy distribution.
李洪蛟1, 2, 3，李 臣4，张文龙5. 注浆钻孔围岩塑性区形态和弹性应变能量分布特征研究[J]. 煤炭与化工, 2023, 46(12): 1-5.
Li Hongjiao 1, 2, 3, Li Chen 4, Zhang Wenlong 5. Study on plastic zone morphology and elastic strain energy distribution characteristics of surrounding
rock in grouting borehole. CCI, 2023, 46(12): 1-5.
