Research purposes: Geotechnical anchoring is an important branch in geotechnical engineering. It has been widely used in civil engineering, mining, hydropower and other engineering filed. However, the study on mesoscopic load transfer mechanism of anchorage structure is still lack. The particle-flow simulation model is established based on field test in this paper and the features of the axial force and shear stress distributions along the anchor rod and meso-mechanical feature of surrounding rock and soil mass is fully analyzed. Research conclusions: (1) The simulation model of anchorage structure is established and the validity of simulation model is verified by comparing the experiment data obtained from on-site pullout test and the simulation mode. (2) The load transfer mechanism of anchorage structure is analyzed, and the distribution of interfacial shear stress along the direction of anchor is uneven: at elastic-viscous stage, the distribution of the interfacial shear stress and the axial force are monotonic decreasing curves; at the elastic-plastic stage, the peak value of the interfacial shear stress is located at the boundary between the elastic-plastic deformation area and the elastic-viscous deformation area, and with the increase of the pullout load, the peak value of the interfacial shear stress increases and the peak value point moves to the anchor end. (3) No matter by gravity or by the pull-out load, the strong contact force is perpendicular to weak contact force between soil particles. The soil particles of the surrounding anchor hole will rearrange by the pull-out load, which results in a strong deflection of the strong contact force and the weak contact force direction. (4) The simulation method and results of this paper have some reference value for design and mechanical analysis of similar anchorage structure.
HUANG Shenggen, PANG Decong, WU Minglei. , {{custom_author.name_en}}et al.
DEM Numerical Simulation Research on the Load Transfer Mechanism of Anchorage Structure[J]. Journal of Railway Engineering Society, 2020, 37(1): 12-17
[1] Farmer I. Stress Distribution along a Resin Grouted Rock Anchor[J]. International Journal of Rock Mechanics & Mining Sciences & Geomechanics, 1975(11):347-351. [2] Yu T Z, Xian C J. Behaviour of Rock Bolting as Tunnelling Support[J]. International Journal of Rock Mechanics & Mining Sciences & Geomechanics Abstracts, 1983(22):87-92. [3] Hyett A J, Moosavi M, Bawden W F. Load Distribution along Fully Grouted Bolts with Emphasis on Cable Bolt Reinforcement[J]. International Journal for Numerical & Analytical Methods in Geomechanics, 2015(7):517-544. [4] 黄明华, 周智, 欧进萍. 全长黏结式锚杆锚固段荷载传递机制非线性分析[J].岩石力学与工程学报, 2014(S2):3992-3997. Huang Minghua, Zhou Zhi, Ou Jinping. Nonlinear Analysis on Load Transfer Mechanism of Wholly Grouted Anchor Rod along Anchoring Section[J]. Chinese Journal of Rock Mechanics and Engineering, 2014(S2):3992-3997. [5] 贺若兰, 张平, 刘宝琛. 锚杆拉拔试验的理论和数值分析[J]. 岩土力学, 2006(S2):855-859. He Ruolan, Zhang Ping, Liu Baochen. Theoretical and Numerical Analysis of Bolt Pull-Out Test[J]. Rock and Soil Mechanics, 2006(S2):855-859. [6] 叶根飞. 岩土锚固荷载传递规律与锚固特性试验研究[D]. 西安:西安科技大学, 2012. Ye Genfei. Law of Anchorage Load Transfer and Experimental Study on Anchoring Characteristics[D]. Xi′an:Xi′an University of Science and Technology, 2012. [7] Bhandari A, Jie H. Investigation of Geotextile-soil Interaction under a Cyclic Vertical Load Using the Discrete Element Method[J]. Geotextiles & Geomembranes, 2010(1):33-43. [8] Sylvestre F. Analytical Study of Induced Anisotropy in Idealized Granular Materials: Rothenburg, L; Bathurst, R J Geotechnique V39, N4, Dec 1989, P601-614[J]. International Journal of Rock Mechanics & Mining Sciences & Geomechanics Abstracts, 1990(3):135.