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.

To adapt to higher and steeper slope environments, this paper proposes a new type of support structure called an anchored frame pile. The study designed and conducted a series of shaking table tests with three-way loading. The acceleration field of the slope, bedrock and overburden layer vibration variability, Fourier spectra, pile dynamic earth pressure, anchor cable force, and damage were analyzed in detail. The results indicate that the overall effectiveness of anchored frame piles for slope reinforcement is superior, and the synergistic impact of front and back piles is evident. Anchor cables effectively reduce the variability of bedrock and overburden layer vibrations. A zone of acceleration concentration always exists at the shoulder of a slope under seismic action. The dominant Fourier frequency in the Y direction of the slope is 11.7687 Hz under Wolong seismic, and the high-frequency vibrations of the upper overburden layer are significantly stronger than those of the bedrock. Slopes under 0.4 g earthquakes first form cracks at the top and then expand downward through them. Under seismic action, the peak dynamic earth pressure in front of the front pile occurs near the bottom of the pile, and the dynamic earth pressure behind the pile occurs near the slip surface. The peak dynamic earth pressure of the back pile occurs at the top of the bedrock. The slope damage is significant at 0.6 g. At this point, the peak dynamic soil pressure at the top of the front pile measures 9.5 kPa, while the peak dynamic soil pressure at the bottom reaches 24.3 kPa. Below the sliding surface of the front pile and on top of the bedrock of the back pile are the critical areas for prevention and control. Elevating the prestressing of the anchor cables will help enhance the synergy between the anchor cables and the piles. Simultaneously, it will reduce the variability of vibration in the bedrock and overburden, thereby improving the stability of the slopes.

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/).

To clarify the effect of various anchor cable failure modes on the dynamic responses of slopes, the FLAC3D software was redeveloped. Constitutive models of cable elements in different anchor cable failure modes were proposed and embedded into the main program of slope dynamic calculation. The axial force, acceleration, and displacement responses in different anchor cable failure modes were compared and analyzed. The effects of seismic parameters on the anchor cable failure modes were also investigated. A matching relationship between the ultimate load-bearing capacities of the anchorage, anchoring interface, and tendon was proposed. The results reveal that the seismic intensity causing anchor cable damage in anchorage failure mode (AFM) and grouting body failure mode is 0.2g-0.3 g lower than that in tendon failure mode. At the moment of failure, the stress released by the anchor cable in AFM is the highest, with the most evident instantaneous slope acceleration fluctuation. In the collaborative seismic design of the anchorage, anchoring section, and anchor tendon, the ultimate load-bearing capacities of the anchorage and anchoring interface should be increased by 1.8 times to match the tensile bearing capacity of the tendon. This study provides a reference for the seismic anchorage design of slopes and offers suggestions for selecting seismic design parameters for anchor cables.

The control and early warning of landslide induced by rainfall have always been the emphasis and difficulty of geological disaster prevention and mitigation. In this study, a slope similarity model was developed based on the landslide at Xiongjia Mountain quarry in Yingjiang County, Yunnan Province, China. A new type of the negative Poisson's ratio structural (NPR) anchor cable and the ordinary prestressed anchor cable (abbreviation PR anchor cable) at model scale were used as slope reinforcement materials. A physical model experiment was carried out to examine the reinforcement mechanism and control effect of rainfall-induced landslides by monitoring and analyzing the evolution characteristics of volumetric water content, pore water pressure, vertical earth pressure, and anchor cable force. The results show that the abnormality of the monitoring curve of soil hydraulic parameters corresponds well with the shallow local slump of the slope. The NPR anchor cable is more sensitive to the redistribution of the internal stress field of the slope induced by rainfall, confirming the law of sudden drop in the force of the NPR anchor cable and local deformation in the slope. In addition, the NPR anchor cable produces a high-stress energy-absorbing control function by virtue of the constant resistance and large deformation characteristics, which effectively suppresses the large deformation of the slope and promotes the slope to reach a secondary equilibrium state. Furthermore, the NPR anchor cable force shows a significant deformation-immediate sliding dynamic law with an initial spike followed by sudden drop before the landslide.

Prestress loss of anchor cables can cause a change in the internal force for the support structure of a foundation pit or slope, which may cause engineering accidents. The coupling effect between an anchor cable and the creep of rock and soil is the main factor that leads to the loss of prestress of the anchor cables. However, the traditional Hooke-Kelvin (H-K) viscoelastic model could not accurately predict the long-term loss of prestress. To solve this problem, based on the H-K viscoelastic model, a new H-3K viscoelastic model was proposed, consisting of two generalized Kelvin bodies connected in parallel, and its creep equation and relaxation equation were also derived. Focusing on slope engineering in Longnan City, Gansu Province, China, the prestress of anchor cables calculated by the proposed model were compared with the monitoring data. The result that the H-K creep coupling model is more accurate in predicting prestress loss of anchor cables in the initial stage, but from a long-term perspective, the H-3K creep coupling model provided a more accurate prediction. By connecting more generalized Kelvin bodies in parallel, stress shared by the elastic body can be reduced and stress loss due to anchor cable relaxation can be approximately compensated for to make the prediction results closer to the monitored values. However, when there are more than three Kelvin bodies in parallel, the model prediction results will change only slightly. Therefore, the H-3K creep coupling model is sufficient for practical engineering.