摘要
为进一步探讨采动巷道在支承压力作用下的破坏机理,以3种典型的应力主导类型巷道为研究对象,综合采用数值模拟试验及理论分析,研究各类巷道在采动影响下塑性区发生二次扩展的演化特征,揭示采动影响下各类动压巷道的围岩变形机制。结果表明:巷道开挖后围岩形成的初始塑性区形态与原岩地应力分布有关,采动影响下不同应力主导类型巷道塑性区二次扩展呈现不同的演化特征。双向等压巷道围岩塑性区呈现圆形—椭圆形—蝶形演化特征;垂直应力主导巷道塑性区始终表现为蝶形形态;水平应力主导巷道塑性区由竖向蝶形演化为水平椭圆形。应力由巷道围岩浅部向深部呈现先增加后减小的梯度变化趋势,偏应力集中程度越大,围岩变形破坏程度越大。围岩偏应力分布形态与塑性区具有对应关系,塑性区二次扩展与采动前后的偏应力环境相关,其形态特征是在初始不可逆塑性区基础上叠加采动作用产生的塑性区再扩展形式。根据塑性区二次扩展机制,获得采动影响下不同应力主导类型巷道围岩变形规律,水平应力主导巷道围岩变形量最小,等压巷道次之,垂直应力主导巷道最剧烈,基于此提出差异化支护方式,通过预判塑性区形态,抑制塑性区扩展,加强塑性区扩展剧烈部位的支护,实现巷道围岩稳定控制。
To further explore the failure mechanism of mining roadway subjected to abutment pressure,taking three typical stress-dominated roadways as the research object,the evolution characteristics of secondary expansion of plastic zone in various roadways under the influence of mining were studied by numerical simulation test and theoretical analysis,and the surrounding rock deformation mechanism for various dynamic pressure roadways under the influence of mining was revealed.The results show that the shape of the initial plastic zone formed in the surrounding rock after roadway excavation is related to the distribution of the in-situ stress.Under the influence of mining,the secondary expansion of the plastic zone for roadways with different dominant stress types shows different evolution characteristics.The plastic zone for the bidirectional equal-pressure roadway is characterized by circular-elliptical-butterfly evolution;that for the vertical stress-dominated roadway always presents a butterfly shape;and that for the horizontal stress-dominated roadway evolves from a vertical butterfly shape to a horizontal ellipse shape.The stress of the roadway surrounding rock displays a gradient change trend of first increasing and then decreasing from the shallow part to the deep part.The higher the degree of deviatoric stress concentration,the more severe the deformation and failure of surrounding rock.The distribution pattern of deviatoric stress in the surrounding rock has a corresponding relationship with the plastic zone,and the secondary expansion of the plastic zone is related to the deviatoric stress environment before and after mining.Its morphological characteristics represent the superposition of mining-induced plastic zone re-expansion on the initial irreversible plastic zone.According to the secondary expansion mechanism of the plastic zone,the surrounding rock deformation laws for roadways with different dominant stress types under the influence of mining were obtained.The surrounding rock deformation for the horizontal stress-dominated roadway is the mildest,followed by that for the bidirectional equal-pressure roadway,and that for the vertical stress-dominated roadway is the most severe.Accordingly,a differentiated support method was proposed.The stability control of roadway surrounding rock is realized by predicting the shape of the plastic zone,inhibiting the expansion of the plastic zone,and strengthening the support in the parts with intense expansion of the plastic zone.
作者
田芯宇
王卫军
马谕杰
袁超
舒仕海
葛莎
TIAN Xinyu;WANG Weijun;MA Yujie;YUAN Chao;SHU Shihai;GE Sha(School of Resources Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan,Hunan 411201,China)
出处
《采矿与安全工程学报》
北大核心
2026年第2期318-329,共12页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(U24A2086,52374088,52274080)。
关键词
采动影响
塑性区
二次扩展
偏应力
围岩变形
mining disturbance
plastic zone
secondary expansion
deviatoric stress
surrounding rock deformation
