(1. School of Civil Engineering，Sichuan Agricultural University，Dujiangyan，Sichuan 611830，China；2. Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction，
Sichuan Agricultural University，Dujiangyan，Sichuan 611830，China)
摘要Based on 3D printing and physical model test method，artificial irregular columnar jointed rock mass specimens with seven different dip angles were prepared by one-shot moulding method where brittle green wax was chosen as 3D printing material to print irregular columnar joint network in which white cement slurry was poured. Conventional triaxial compression tests were performed on these artificial irregular columnar jointed rock mass specimens，from which their strength and deformation anisotropy and typical failure modes were derived. From the experimental results，it showed that the strength，deformation modulus and lateral strain ratio of irregular columnar jointed rock mass exhibited moderate or high anisotropy and confining pressure had significant effect on its mechanical anisotropy. Furthermore，the typical failure modes of irregular columnar jointed rock mass under conventional compression condition had been classified into four kinds，that was，Y-shaped conjugate shear failure along columnar joints，splitting failure along both intact column and columnar joint，shear slip failure along columnar joint and axial splitting of intact columns. Finally，the influence of 3D printed green wax irregular columnar joint network on mechanical behaviors of irregular columnar jointed rock mass was analyzed.
Abstract：Based on 3D printing and physical model test method，artificial irregular columnar jointed rock mass specimens with seven different dip angles were prepared by one-shot moulding method where brittle green wax was chosen as 3D printing material to print irregular columnar joint network in which white cement slurry was poured. Conventional triaxial compression tests were performed on these artificial irregular columnar jointed rock mass specimens，from which their strength and deformation anisotropy and typical failure modes were derived. From the experimental results，it showed that the strength，deformation modulus and lateral strain ratio of irregular columnar jointed rock mass exhibited moderate or high anisotropy and confining pressure had significant effect on its mechanical anisotropy. Furthermore，the typical failure modes of irregular columnar jointed rock mass under conventional compression condition had been classified into four kinds，that was，Y-shaped conjugate shear failure along columnar joints，splitting failure along both intact column and columnar joint，shear slip failure along columnar joint and axial splitting of intact columns. Finally，the influence of 3D printed green wax irregular columnar joint network on mechanical behaviors of irregular columnar jointed rock mass was analyzed.
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2023, Vol. 42 
