Rainfall-induced landslide mitigation remains a critical research focus in geotechnical engineering, particularly for safeguarding buildings and infrastructure in unstable terrain. This study investigates the stabilizing performance of slopes reinforced with negative Poisson's ratio (NPR) anchor cables under rainfall conditions through physical model tests. A scaled geological model of a heavily weathered rock slope is constructed using similarity-based materials, building a comprehensive experimental setup that integrates an artificial rainfall simulation system, a model-scale NPR anchor cable reinforcement system, and a multi-parameter data monitoring system. Real-time measurements of NPR anchor cable axial forces and slope internal stresses were obtained during simulated rainfall events. The experimental results reveal distinct response times and force distributions between upper and lower NPR anchor cables in reaction to rainfall-induced slope deformation, reflecting the temporal and spatial evolution of the slope's internal sliding surface-including its generation, expansion, and full penetration. Monitoring data on volumetric water content, earth pressure, and pore water pressure within the slope further elucidate the evolution of effective stress in the rock-soil mass under saturation. Comparative analysis of NPR cable forces and effective stress trends demonstrates that NPR anchor cables provide adaptive stress compensation, dynamically counteracting internal stress redistribution in the slope. In addition, the structural characteristics of NPR anchor cables can effectively absorb the energy released by landslides, mitigating large deformations that could endanger adjacent buildings. These findings highlight the potential of NPR anchor cables as an innovative reinforcement strategy for rainfall-triggered landslide prevention, offering practical solutions for slope stabilization near buildings and enhancing the resilience of building-related infrastructure.
The impacts of natural boulders carried by debris flows pose serious risks to the safety and reliability of structures and buildings. Natural boulders can be highly random and unpredictable. Consequently, boulder control during debris flows is crucial but difficult. Herein, an eco-friendly control system featuring anchoring natural boulders (NBs) with (negative Poisson's ratio) NPR anchor cables is proposed to form an NB-NPR baffle. A series of flume experiments are conducted to verify the effect of NB-NPR baffles on controlling debris flow impact. The deployment of NB-NPR baffles substantially influences the kinematic behavior of a debris flow, primarily in the form of changes in the depositional properties and impact intensities. The results show that the NB-NPR baffle matrix successfully controls boulder mobility and exhibits positive feedback on solid particle deposition. The NB-NPR baffle group exhibits a reduction in peak impact force ranging from 29% to 79% compared to that of the control group in the basic experiment. The NPR anchor cables play a significant role in the NB-NPR baffle by demonstrating particular characteristics, including consistent resistance, large deformation, and substantial energy absorption. The NB-NPR baffle innovatively utilizes the natural boulders in a debris flow gully by converting destructive boulders into constructive boulders. Overall, this research serves as a basis for future field experiments and applications. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).
This study investigates the vulnerability of expansive soil slopes to destabilization and damage, particularly under intense rainfall, due to their heightened sensitivity to moisture. Focusing on a project in Yunnan Province, numerical simulation software is employed to address slope stability challenges. Meanwhile, the soil mechanical parameters of this study were acquired through experimentation. The analysis considers six conditions: unsupported, conventional anchor and stabilizing pile reinforcement, and NPR (Negative Poisson's ratio) anchor and stabilizing pile reinforcement, evaluated under both normal and rainstorm conditions. The research outcomes reveal noteworthy insights: (1) The efficacy of NPR anchors in mitigating deformation in expansive soil landslides is investigated, broadening their application potential, particularly in restricting maximum slope displacement compared to conventional anchors. (2) No significant difference in safety factors for slope stability is observed between NPR and conventional anchors. Under rainstorm conditions, safety factors are 1.39 and 1.32 for NPR and conventional anchor and stabilizing pile support, respectively, while under normal conditions, they are 1.42 and 1.39. (3) The NPR anchor, in contrast to the conventional anchor, ensures a more uniform force distribution across the stabilizing pile. (4) While combined support structures contribute to slope stabilization, NPR anchors surpass conventional anchors in limiting slope displacement.