Deformation mechanisms of Dazu Rock Carvings ceiling based on negative Poisson’s ratio anchor support

Stone cultural relics represent an important component of China’s cultural heritage. Yuanjue Cave in Chongqing has developed severe stability problems after over 1000 years of weathering, with intersecting cracks (C1, C2, and C3) posing a potential risk of collapse. This study investigates the cave’s deformation and failure mechanisms through geological analysis, physical model experiments employing negative Poisson’s ratio (NPR) anchors, and numerical simulations. The structural conditions are characterized by unloading and interlayer cracks, which facilitate water infiltration. NPR anchor support effectively limited ceiling settlement to within 0.3 mm, significantly enhancing stability, particularly at crack intersections and the cave entrance. Settlement along the C1 crack was associated with the cantilevered north rock mass; however, NPR anchors effectively mitigated rainfall-induced deformation. These findings demonstrate the effectiveness of NPR anchors in controlling cave deformation and provide valuable technical references for the protection and reinforcement of stone cultural relics.