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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.

期刊论文 2025-05-21 DOI: 10.3390/buildings15101745

The seismic response of cable-stayed bridges is characterised by complicated interactions between the deck and the towers. These are influenced by the possible damage in the structure, and also by design choices or constraints such as the tower shape, the span, the cable arrangements, the support conditions and the type of foundation soil. The aim of this work is to assess the influence of these effects on the seismic behaviour of a large number of cable-stayed bridge finite element models. The results of the nonlinear dynamic analyses show the importance of the tower geometry. This is especially significant in short-span bridges with abrupt changes in the inclination of the lateral tower legs, which can lead to large levels of damage in the form of concrete cracking, reinforcement yielding and overall energy dissipation. Finally, design recommendations are proposed to improve the seismic response of the towers.

期刊论文 2025-05-01 DOI: 10.1016/j.istruc.2025.108752 ISSN: 2352-0124

Climate change is influencing traditionally stable factors such as meteorological characteristics and soil conditions, impacting the planning process of electrical energy grids, especially energy cables. Supported by real-life data from the metropolitan region of Hamburg, this study examines the sensitivity of electric energy cables to seasonal and climate related changes, aiming to address inevitable future climate impacts. Using the thermal impedance model by the International Electrotechnical Commission, combined with 32 years of local soil and weather data, permissible current levels were calculated for a specific cable configuration. Comparisons with static boundaries reveal that shifts in environmental conditions can undermine the planning process, affecting maximum current limits and casting doubt on the current method's validity. Analysis shows that seasonal transitions significantly alter soil parameters within each annual cycle, causing up to a 10 % variation in energy transfer potential, depending on soil, cable, and regional specifics. Static standards also overestimate ampacity by up to 12 % for the studied region and timeframe. Climate change leads to shifting soil and weather conditions, causing unused energy transfer capacities, overestimations, and potential structural damage. As climate effects intensify, both seasonal and historical shifts are expected to have greater impacts, highlighting the limitations of the current static planning model without additional monitoring systems. As limited transmission capacities increasingly demand costly congestion management and equipment redundancies diminish, the need to optimize current resources and plan for a changing future becomes even more critical.

期刊论文 2025-04-01 DOI: 10.1016/j.rser.2025.115348 ISSN: 1364-0321

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.

期刊论文 2025-02-07 DOI: 10.1038/s41598-024-83382-8 ISSN: 2045-2322

Thermal backfill is an integrated part of underground electrical cable infrastructures systems, ground heat source pumps and radioactive waste repositories, as it minimizes resistance to heat transfer away from these systems. The heat transfer capacity and current carrying capability of underground electrical cables are significantly affected by thermal conductivity of backfill material and the surrounding soil media. Therefore, this research paper compares the thermal conductivity and shrinkage results of compacted (low to high densities) fly ash- and sand-bentonite mixtures with bentonite contents of 30%, 50%, 60%, 80% and 100%. The thermal conductivity of mixtures increased from 1.05 Wm-1K-1 to 1.20 Wm-1K-1 with the addition of fly ash content from 20 to 70% by weight in bentonite. The thermal conductivity bentonite-sand mixture was also found to be increased from 1.21 Wm-1K-1 to 1.83 Wm-1K-1 with increasing sand content. Additional to this, the bentonite-sand and bentonite-fly ash-based backfill materials surrounding heat-sensitive structures experience shrinkage and desiccation cracking due to thermal drying. Therefore, the desiccation volumetric shrinkage tests of bentonite-sand and bentonite-fly ash mixtures were conducted and found that the presence of sand or fly ash reduces shrinkage strain. Based on the experimental results, this study suggests a sustainable utilization of fly ash up to 50%-70% as an effective thermal backfill material in electrical cable infrastructure systems. Thus, the application of fly ash as a construction material reduces environmental impact and cost, aligning with the goals of sustainable development.

期刊论文 2025-02-01 DOI: 10.1007/s10035-024-01482-8 ISSN: 1434-5021

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/).

期刊论文 2025-02-01 DOI: 10.1016/j.jrmge.2024.03.027 ISSN: 1674-7755

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.

期刊论文 2025-01-01 DOI: 10.1016/j.soildyn.2024.109077 ISSN: 0267-7261

Insufficient understanding of the stress-strain behavior of pavements built over backfilled trenches, particularly with recycled aggregates, often leads to overdesign or overcompaction, raising costs and project delays. This research investigates how compaction levels during backfilling impact the pavement performance over these trenches. Various recycled material mixtures, both unbound and cement-treated, are compared with conventional crushed rock. Investigations included repeated load triaxial (RLT) tests, microstructural analysis with scanning electron microscopy, environmental assessments, and modeling with FlexPAVETM, a pavement response and performance analysis software. RLT test results were incorporated into the FlexPAVETM models by utilizing established constitutive resilient modulus models. Stress-strain responses of pavements over recycled aggregate backfill, compacted with standard and modified Proctor efforts, were compared with those over crushed rock and natural clay subgrades. Outcomes revealed that the standard compaction energy was sufficient for the desired performance. Fatigue and rutting strains with recycled mixtures closely resembled those with crushed rock, making them viable green alternatives. Pavements over backfilled trenches exhibited 1.5 and 1.8 times longer fatigue and rutting lives, respectively, than those over natural clay subgrades.

期刊论文 2025-01-01 DOI: 10.1139/cgj-2024-0135 ISSN: 0008-3674

As renewable energy demand increases, protecting subsea cables from ship anchor damage has become essential. This research comprises numerical simulations of the anchor penetration process in Baltic Sea sand (for an AC-14, a Hall and a Spek anchor). We apply a coupled Eulerian-Lagrangian (CEL) framework and a hypoplasticity constitutive model to analyze the influence of different anchor characteristics on penetration depth and seabed stress distributions. We conducted investigations under high velocities (v >= 1 m/s) with focus on inertial effects only. Furthermore, this study introduces stress circles to visualize a simplified anchor- induced spatial stress distribution in the seabed. Findings show that heavier anchors and slower drag velocities generally result in deeper anchor penetrations. Fluke geometry significantly affects penetration depth, with pointed designs penetrating more deeply. The observed trends align with previous results from centrifuge tests and numerical modeling of ship anchors. This research improves understanding of soil-structure interaction in maritime environments, offering insights for the protection of subsea installations in the Baltic Sea and similar regions.

期刊论文 2024-12-15 DOI: 10.1016/j.oceaneng.2024.119674 ISSN: 0029-8018

This research examines the seismic behavior of a cable-stayed bridge featuring concrete-filled steel tube (CFST) pylons, which includes the seesaw system. The objective of the study is to assess the efficacy of the seesaw system in mitigating the seismic response of the bridge across various earthquake scenarios, while also accounting for the implications of soil-structure interaction (SSI). A comprehensive finite element model of the bridge is constructed, incorporating the CFST pylons, cable system, and the novel seesaw energy dissipation system. This model is tested against a range of ground motions that reflect different seismic hazard levels and characteristics. The impact of SSI is analyzed through a series of parametric studies that explore various soil conditions and foundation types. The findings indicate that the implementation of the seesaw system markedly decreases the seismic demands placed on the bridge structure, particularly regarding deck displacements, pylon base shear, and cable forces. Furthermore, the study underscores the significant influence of SSI on the dynamic behavior of the bridge system, emphasizing the necessity of its inclusion in seismic design and analysis. This research enhances the understanding of seismic protection strategies for cable-stayed bridges, providing valuable insights into the advantages of integrating energy dissipation systems and recognizing the importance of SSI effects in evaluating seismic performance.

期刊论文 2024-12-01 DOI: 10.3390/geohazards5040051
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