基于光弹法的颗粒材料直剪试验剪切滑移区研究

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中图分类号：TU411.7 文献标志码：A 文章编号：2096-6717（2025）03-0012-09

Study of shear slip zone in direct shear test of granular materialsbasedonphotoelasticmethod

HU Wentao1，XIAO Jin1，YIN Jianghao'，GENG Daxin1，XU Changjie 1 LI Shunwen1，WU Wenbing²

（1.Jiangxi Provincial KeyLaboratoryofGeotechnical Engineering Infrastructure Securityand Control; Engineering Research & Development Centre for Underground Technology of Jiangxi Province，East China Jiaotong University， Nanchang 33Ool3，P.R.China; 2.Faculty of Engineering; Engineering Research Centerof Rock-Soil Drillng &. Excavation and ProtectionofMinistryof Education，China Universityof Geosciences，Wuhan43oo74，P.R.China）

Abstract： The development pattern and distribution characteristics of the shear zone ofthe particle direct shear testdeterminethe strengthof the particle body，but it is not easy toobserve.The directshear test of transparent polycarbonate particles was carred out using a homemade test device.Based on the principle of photoelastic method，the development process of force chain，the development patern of main contact angle and shear slip surface of particles were studied by observing the shear mechanical properties，stress chain distribution and displacement field of particles，and the simulation analysis was carredout in PFC2D.The tests show that： the stress shielding phenomenon exists in the force chain distribution of the particle system during the direct shear process;the strong force chain，contact angle and main stress direction of the particle system aredeflected，and the deflection characteristics are basically the same;the particles form an arch-shaped shear slip surface during the shear process，and form an arch-shaped slip shear zone together with the horizontal shear surface. The arch slip zone forms at the beginning of shear and continues throughout the shear process. At peak shear stress，the height of the arch-slip zone is proportional to the initial normal force and is between （13-15） d50 thick. The arch slip zone graduallydecreases during the residual stress phase，and the arch slip zone gradually tends to a steady state，and the height of the arch slip zone under different initial normal forces does not difer significantly during the residual stress phase，while thickness varies between （8-9）d50 ：

Keywords： particulate matter；photoelastic method；straight shear test；shear expansion （contraction）；arch shear zone

离散颗粒的聚集体具有不连续性、各向异性等特殊性质，直剪试验是常用的研究颗粒剪切力学性能的试验方法。（剩余12047字）