Le, Hoang-KhanhHoang-KhanhLeMENG-CHIA WENGHo, Thi Kim ThoaThi Kim ThoaHo2026-03-242026-03-242024https://www.scopus.com/inward/record.uri?eid=2-s2.0-85200741820&doi=10.1007%2F978-981-99-9722-0_59&partnerID=40&md5=13102193f4d0ba809a0559053e4fe880https://scholars.lib.ntu.edu.tw/handle/123456789/7367635th International Conference on Geotechnics for Sustainable Infrastructure Development, GEOTEC 2023, 14 December 2023 through 15 December 2023, HanoiThe mechanical properties of metamorphic rocks are affected by the existence of foliation, which induces apparent anisotropy and heterogeneity. This study performed a series of pull-off and direct shear tests to investigate the tensile strength, peak, and residual shear strength of schist foliation. Finally, the effect of grout reinforcement on fractured foliation was evaluated. The key findings include: (1) A nonlinear failure criterion for foliation was adopted to reasonably describe the failure envelope of schist; (2) Considering the grout reinforcement on fractured foliation, the strength of grouted schists significantly increased. The high roughness strongly contributes to the grout reinforcement on the schist foliation; (3) The severely fractured specimen with a rough surface reflects both material and interface failures, while the specimen with a low roughness exhibits interface failure. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.Cement-filled metamorphic rockDirect shear testFailure mechanismJoint roughnessShear strengthconference paper10.1007/978-981-99-9722-0_592-s2.0-85200741820