1. School of Mines,Key Laboratory of Deep Coal Resource Mining under Ministry of Education of China,China University of Mining and Technology,Xuzhou 221116,China;2. School of Environment Science and Spatial Informatics,China University of Mining and Technology,Xuzhou　 221116,China

根系损伤是西部干旱半干旱生态矿区开采植被退化的重要诱因,以神东矿区为背景,通过调研总结地表沉降、根系赋存及变形破坏特征,提出采动诱发根系损伤的应变控制和应力控制两类现象。建立等径单根界面剪切脱黏模型,分析开采扰动后根土界面的"弹性-滑移-脱黏"三阶段受力过程,得出根土界面剪应力-应变关系,揭示三种典型损伤的细观力学机制。进一步将矿区优势植物沙柳和沙蒿简化成全长锚固单元和根土复合层,采用FLAC3D研究采动后全长锚固单元和根土复合层宏观响应的受力变形区划特征。结果表明:高拉应力是采空区上方全长锚固单元损伤的控制因素;表底层受力的非一致性和非整体性是引发采空区边界附近全长锚固单元损伤的控制因素。采空区上方根土复合底层剪应力水平高于表层,更容易形成大面积的压剪损伤区;采空区边界及以外根土复合表层拉应力水平高于底层,更容易形成拉伸损伤区。

Roots damage is an important inducement of vegetation degradation in western arid and semi-arid mining ar- ea when mining. Based on field investigation and related literatures on the background of Shendong mining area,this paper proposes two phenomena of roots damage induced by mining,strain controlling and stress controlling. Through building the interfacial shear debonding model of single equal-diameter root,the “ elastic-slipping-debonding” three stages of root-soil interface stress deformation process induced by mining are studied. The shear stress-strain curve of root-soil interface is deduced,and then the mesoscopic mechanics of three typical roots damage are revealed. Further- more,by simplifying the dominant plants salix psammophila and artemisia desertorum into full length anchorage unit and root-soil composite layer,the force-deformation zoning characteristics of macroscopic response to mining is modeled with FLAC3D . The results show that high tensile stress is the control factor for full length anchorage unit above the gob span and that non-consistency and non-integral of force is the control factor for full length anchorage unit near the boundary of gob. The shear stress level on the bottom of root-soil composite layer above the gob is higher than that on the top,hence,it is easier to form a large area of shear damage area on the bottom of root-soil composite layer above the gob. The tensile stress level on the bottom of root-soil composite layer along and outside the boundary of gob is low- er than that on the top,hence,it is easier to form a large area of tensile damage area on the top of root-soil composite layer along and outside the boundary of gob.

国家重点基础研究发展计划(973)资助项目(2013CB227904)；国家重点研发计划资助项目(2016YFC0501107)；江苏省普通高校学术学位研究生科研创新计划资助项目(KYLX16_0562)；

Pan Dongjiang,Zhang Nong,Zhao Yiming,et al. Characteristics and mesoscopic mechanics of vegetation roots damage induced by mining in western mining area[J]. Journal of China Coal Society,2017,42(2):373-380.