Characterization of Negative Poisson’s Ratio anchor cable forces in loess slopes

In the realm of slope monitoring and reinforcement, traditional prestressing anchor cables are extensively used. However, these conventional methods often face limitations when applied to loess slopes, such as potential issues with stress concentration and insufficient adaptability to the unique mechanical properties of loess, which may lead to challenges in ensuring long-term stability and effective reinforcement. Negative Poisson's ratio (NPR) anchor cables with constant resistance have emerged as a promising alternative, which can better match the engineering demands of loess slopes by providing more uniform stress distribution and adaptive deformation characteristics. The NPR cable's ability to maintain a constant resistance during deformation offers a distinct advantage over traditional methods as it can more effectively accommodate the complex and variable conditions of loess slopes. To investigate the anchoring performance of NPR cables in loess slope, the stress characteristics of NPR cable in loess medium were simulated and analysed by ABAQUS finite element software. First, static and general quasi-static analysis methods were used to simulate the NPR cable under static tensile conditions. The consistency of the simulated constant resistance deformation characteristics with experimental results found in the literature was verified. Second, the interaction model between the NPR cable coupled with the loess medium was established. Its constant resistance was calculated to be about 24.08% larger than that of NPR anchor cable while its plastic deformation was reduced by about 37.14%. The compressive stress on the contact surface between NPR cable and loess was concentrated near the free end of the sleeve, which indicated that the loess was prone to severe damage at the free end. The research results reveal the typical shear failure mechanism of NPR cable in loess medium, which provides an important theoretical basis for prevention of landslides and monitoring of loess slopes.