Mitigation of Dynamic Load-Induced Pipeline Displacements Using EPS Geofoam

Stress-Strain Response Characteristics of Buried Gas Pipelines Under Landslide Action

Typically, triggered by geological hazards such as landslides, ground displacement acts as the main cause for the failure of buried pipelines. To maintain the structural integrity of these pipelines, an in-depth investigation is required to understand how these pipelines, subjected to landslide thrust, respond mechanically. During the research, a refined three-dimensional (3D) finite element model for soil-pipeline interaction was established, as evidenced by existing experimental data, which takes the elastoplastic behavior of the soil and complex contact conditions into consideration. According to a thorough parametric study, on the basis of the model, the effects of pipeline, landslide, and soil vary in their protection, detrimental, and complex trade-off levels. On the one hand, protective measures concerning wall thickness, steel grade, and other similar factors serve to improve resilience; on the other hand, detrimental factors such as burial depth and soil stiffness escalate the possibility of failure risk. Notably, the influences related to landslide extent and pipe diameter are not straightforward and monotonic. In other words, when one factor increases, risk may be reduced in one regime and amplified in another. Therefore, words like “wider” or “bigger” should not be equal to “safer” by default. To conclude, based on the results, train-based evaluation is supported, and some practical guidance can be provided for the design and risk assessment for pipelines in areas where geohazards may occur.

Numerical investigation and parametric study of geocell-reinforced embankments under static loading

Geocell reinforcement has been increasingly applied in transportation infrastructure to improve the stability and serviceability of road embankments constructed on weak subgrades. The load transfer mechanism in geocell–soil systems involves complex interactions between soil confinement, lateral restraint, and membrane effects, which makes the design process challenging using conventional empirical approaches. This study presents a numerical and data-driven framework to investigate the performance of geocell-reinforced embankments subjected to static loading. Finite element simulations were conducted, considering variations in geocell location, geocell height, and distributed load. The simulations are automated through the PLAXIS Python API to generate a comprehensive dataset of embankment responses. A predictive model is then developed using Gene Expression Programming to estimate the settlement of reinforced embankments. A parametric study is subsequently performed to determine effective design configurations. The proposed framework provides a practical tool for improving the reliability and efficiency of geocell-reinforced embankment design.

Geosynthetic-reinforced soil wall behaviour under high-speed railway moving cyclic loads

With the rapid expansion of high-speed railway (HSR) infrastructure, ensuring the long-term stability of geosynthetic-reinforced soil (GRS) walls under repeated traffic loading is critical. This study investigates the dynamic mechanical behaviour of HSR GRS walls using a combination of physical model tests and three-dimensional dynamic numerical simulations. A moving vehicle loading device developed by the authors was employed to realistically simulate the driving effects of high-speed trains, addressing the limitations of traditional sinusoidal loading systems. Results indicate that wall crest settlement increases rapidly during the initial 500 cycles (contributing ∼50% of total settlement) before exhibiting a continued, albeit reduced, increasing trend. A characteristic ‘bulging’ deformation pattern was observed, with peak horizontal displacements occurring at approximately two-thirds of the wall height. Furthermore, vertical earth pressure exhibited a clear diffusion pattern, attenuating downward from the loading plate. The computed potential failure surface aligns closely with the 0.3H surface (where H is the wall height) specified in current design codes, providing a robust theoretical basis for the seismic and dynamic design of railway retaining structures.

Mechanics of Buried Pipelines Loading under Localized Subsidence: A Three-Dimensional Soil-Arching Approach

The combined effects of localized subsidence-induced size effects and pipe–soil interaction render conventional load calculation theories inadequate for accurately evaluating pipeline loads after foundation subsidence. To overcome this limitation, the 3D transfer characteristics of vertical loads acting on buried pipelines under localized subsidence are investigated from the perspective of the spatial deflection of 3D principal stresses and the evolution of stress trajectories. On this basis, a 3D soil arching model is established by incorporating the combined contributions of overburden self-weight, lateral passive earth pressure, and boundary friction. Further, a 3D pipe–soil load-transfer framework consisting of the top zone, the up zone, and the gap zone is constructed, through which a unified analytical expression for the vertical load at the pipe crown under localized subsidence is derived. The analytical predictions are validated against data from two laboratory trapdoor tests, which reveal considerable differences in pipeline crown loads between tests and pronounced variations in vertical earth pressure within the same test as trapdoor displacement increases. The results demonstrate that the proposed model provides a more comprehensive representation of stress redistribution in deformation zones induced by pipe–soil interaction under localized subsidence. By explicitly incorporating the geometric configuration and mechanical characteristics of the soil segments within the collapse area, the model offers enhanced explanatory power and predictive accuracy compared with traditional approaches.

Seismic Response and Failure Mechanisms of Tunnels Constructed Using the Pipe Roof Preconstruction Method

Analysis of Geosynthetic-Reinforced Tailings Dam Slopes Subjected to Surface Loads

This study presents an extensive numerical investigation of the stability of a geosynthetic-reinforced tailings dam embankment slope subjected to surface loads from retained pyrite tailings slurry upstream of the dam. The analysis was performed on an embankment with an inclination of 1V:2.5H on the upstream slope and 1V:2H on the downstream slope. The dam embankment rests directly on previously deposited pyrite tailings that have dried over time and are sufficiently consolidated to support the embankment. The variable parameters considered in this study include the geosynthetic reinforcement length across the failure zone, effective cohesion ( c′ ), effective angle of internal friction ( ϕ′ ), total unit weight of the embankment clay ( γ ), and the number of reinforcement layers ( N ). The results revealed that the safety factor of the embankment slope increased with the increasing length of the geosynthetic reinforcement across the failure zone, shear strength parameters c’ and φ ʹ , and unit weight, $$\gamma $$ . Increasing the total unit weight of embankment clay from 13 kN/m 3 to 21 kN/m 3 resulted in a 61%, 47%, and 30% increase in the factor of safety for N  = 13, 7, and 4, respectively. Additionally, for every 1 kPa increase in c’, which is a very low value, the safety factor increased on average by 2.5%, 2.2%, and 1.9% for N  = 13, 7, and 4, respectively. The findings of this study contribute to the advancement of safer and more reliable tailings dam designs by offering innovative and cost-effective solutions to engineering challenges.