Presentation Information
[2409]Numerical and experimental investigation of the microscopic strain and stress state in a fault damage zone using 3D-printed models
○Zhe Zhang1, Atsushi Sainoki1 (1. Kmamoto university)
Chairperson: 奈良禎太（京都大学）
Keywords:
3D printing,fault damage zone,digital volume correlation,FLAC3D
Fault damage zones (FDZs) significantly impact rock mass stability, yet their internal stress–strain behavior remains difficult to resolve due to the complex nature of natural rock. This study introduces an experimental-numerical framework combining three-dimensional printing (3DP), X-ray CT-based Digital Volume Correlation (DVC), and FLAC3D simulations to investigate FDZs. 3D-printed specimens with single fractures of varying sizes were tested under uniaxial compression to assess whether 3DP analogs can replicate fault-core behavior. Stress-displacement relations derived from DVC were used to back-calculate fracture mechanical properties, which were then incorporated into FLAC3D simulations. FDZ specimens, composed of a fault core and surrounding fracture disks, were generated using discrete fracture network (DFN) models in 3DEC and imported into Rhino for geometric modeling. Stepwise loading tests inside an X-ray CT system enabled full-field 3D deviatoric strain distributions. The experimental results reveal heterogeneous strain fields, with significant localization along the fault core and perturbations due to interactions between the fault core and surrounding fractures. The measured strain fields align well with FLAC3D simulations, validating the calibrated parameters and FDZ structure. Further simulations show stress concentration and redistribution in the surrounding fracture network, particularly near fracture intersections and fault-core boundaries. This framework provides a reproducible method for linking experimentally measured strain fields with numerically predicted stress evolution in FDZs.