Article
Computer Science, Interdisciplinary Applications
An Zhang, Mingjing Jiang, Dong Wang
Summary: To understand the effects of fabric anisotropy on cyclic liquefaction of sands, undrained cyclic triaxial tests on vertical and horizontal specimens were simulated using the discrete element method. The simulation accurately depicted the anisotropic cyclic responses observed in experiments, showing that the vertical specimen is more susceptible to liquefaction than the horizontal specimen under symmetrical cyclic loading conditions. The study investigated various fabric parameters at the particle scale to gain insights into the macro response and applied anisotropic critical state theory to explore the relationship between macro-mechanical behavior and fabric evolution.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Engineering, Geological
M. A. Hosseini, M. T. Rayhani
Summary: This manuscript presents the results of two shaking table tests on the seismic performance of FRP pile groups in saturated sand. The study found that GFRP piles performed slightly better than CFRP piles in terms of seismic response and could be an alternative material for frictional traditional piles, especially in liquefiable soils.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Chemistry, Physical
T. S. Guruprasad, V. Keryvin, L. Charleux, J. -P. Guin, O. Arnould
Summary: Nano-indentation instrumented tests were conducted on PAN-based and MPP-based carbon fibers to obtain indentation moduli. An improved method considering the buckling mechanisms of crystallites during indentation process was proposed to accurately identify elastic constants. The elastic properties of carbon fibers were used to estimate those of epoxy matrix composites, showing very good agreement with experimental values. Excellent correlation was eventually found between experiments and Finite Element Analyses of carbon fibers' indentation response.
Article
Computer Science, Interdisciplinary Applications
Masahide Otsubo, Sanjei Chitravel, Reiko Kuwano, Hiroyuki Kyokawa, Junichi Koseki
Summary: This study uses the discrete element method (DEM) to simulate the mechanical response of spherical particle assemblies under triaxial loading, and finds that gravity affects both packing properties and liquefaction characteristics. Although inter-particle contacts are maintained during liquefaction under nonzero gravity conditions, the stress-strain relation and stress path are measurably altered. This highlights the importance of considering the potential effect of gravity when interpreting laboratory or DEM results on liquefaction phenomena.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Engineering, Geological
Habib Rasouli, Behzad Fatahi, Sanjay Nimbalkar
Summary: This study experimentally investigated the liquefaction and re-liquefaction resistance of cemented sands under successive liquefaction events. The results showed a decrease in re-liquefaction resistance after the first liquefaction event, followed by an increase in subsequent liquefaction events.
CANADIAN GEOTECHNICAL JOURNAL
(2022)
Article
Engineering, Geological
P. Fardad Amini, D. Huang, G. Wang
Summary: The experimental study on reliquefaction characteristics of sandy soils reveals the dependence of reliquefaction resistance and modulus reduction on strain history and reconsolidation state, while a consistent damping curve is found for all liquefaction and reliquefaction tests.
GEOTECHNIQUE LETTERS
(2021)
Article
Engineering, Geological
Saathoff Jann-Eike, Martin Achmus
Summary: During storm events, excess pore pressures in the soil around offshore foundations can negatively impact the foundation's structural integrity. High-quality laboratory test results are crucial for analytical or numerical calculations. An optimized test program is desired to minimize the number of required tests. This paper presents an extensive test program on three sands, including Resonant Column (RC) and displacement-controlled cyclic Direct Simple Shear (DSS) tests. A shear strain threshold concept is proposed based on the findings, which differentiates the general soil behavior under cyclic loading. The results show that a combination of a few RC, multistage DSS, and DSS tests can quantify the soil response under various boundary conditions, and equations for parameterizing the experimental results are discussed.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2023)
Article
Engineering, Geological
Lin Zhou, Jian-Feng Chen, Ming Peng, Yan Zhu
Summary: A study on the liquefaction resistance of calcareous sands reinforced with polypropylene fibers was conducted, and it was found that increasing fiber content and length improved the resistance to liquefaction.
GEOTEXTILES AND GEOMEMBRANES
(2022)
Article
Engineering, Geological
L. Mele, S. Lirer, A. Flora
Summary: Induced partial saturation is a promising technology for mitigating soil liquefaction risk. Gas dissolution can significantly increase the volumetric strains of soils, which should not be neglected when estimating the beneficial effect of desaturation on liquefaction potential. Additionally, the difference in liquefaction resistance between partially saturated and fully saturated soils is mainly determined by the volumetric component.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2022)
Article
Engineering, Geological
Francisco Humire, Katerina Ziotopoulou
Summary: The study examines the accumulation of shear strains in clean uniform sands exhibiting cyclic mobility behavior under level-ground conditions, finding that the rate of shear strain accumulation is influenced by relative density, cyclic stress amplitude, and effective overburden stress. By analyzing the components of shear strain development, it is concluded that y0 is mainly related to shear strain history, while yd is mainly influenced by cyclic stress amplitude and relative density.
CANADIAN GEOTECHNICAL JOURNAL
(2022)
Article
Engineering, Geological
Jiajin Zhao, Zhehao Zhu, Dexuan Zhang, Hao Wang, Xi Li
Summary: This paper studies the fabric properties during sand liquefaction using 3D constant-volume cyclic triaxial DEM tests. The results show good consistency with experimental data. The evolution of fabric characteristics is assessed using the coordination number and mechanical coordination number. The second-order contact normal fabric tensor is introduced to analyze complex inter-particle contacts and the shear strain is used as a bridge to describe the evolution of coordination number and anisotropy degree.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2024)
Article
Engineering, Geological
Sara Rios, Maxim Millen, Julieth Quintero, Antonio Viana da Fonseca
Summary: The damage caused by earthquakes can be a result of seismic excitation and/or excess pore pressure in the soil. Reduction in soil stiffness due to decreased effective stress affects the seismic response of the soil. Therefore, the level of damage depends on the amount of seismic energy before liquefaction. Developing simplified methods to assess excess pore pressure is crucial for estimating seismic demand and improving building safety.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Geological
Kyle M. Rollins, Sara Amoroso, Paul Andersen, Laura Tonni, Kord Wissmann
Summary: The study compared the untreated area with a full-scale RAP group in silty sand to investigate the liquefaction mitigation capability of RAP. It was found that the use of RAP reduced settlement caused by liquefaction, although the same settlement estimation method resulted in overestimation in the RAP treated area.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2021)
Article
Engineering, Marine
Leiye Wu, Wei Cheng, Zhehao Zhu
Summary: A new constitutive model incorporating fractional plastic flow rule and multiple hardening rules is proposed and validated with medium-dense sand cyclic test results, demonstrating robustness in capturing non-associativity and cyclic mobility of sandy soils. The model is implemented into a finite element code for a numerical case study on seabed soils under cyclic wave loadings, showcasing its practical applications in structure-seabed interactions.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Geological
Giovanni Ciardi, Claudia Madiai
Summary: This article discusses the laboratory test results of colloidal silica grouting for mitigating liquefaction risk. The results show that the dissipated energy at failure is significantly higher in stabilized sand than in untreated sand.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2023)