Article
Computer Science, Interdisciplinary Applications
Fengyuan Wu, Shixiong Wang, Wei Sun, Pengfei Qin, Guanhua Zhang
Summary: This study investigates the effects of granular flow on dry and saturated entraining materials and the force acting on the retaining wall. Numerical simulations are conducted to evaluate the accuracy and effectiveness of the discrete element method (DEM). The study shows that the velocity of granular flow decreases and the normal force acting on the retaining wall decreases significantly due to entrainment. Combining DEM and computational fluid dynamics (CFD), the study also investigates the entrainment of granular flow with saturated path material and finds that the addition of fluid decelerates the entrainment area and reduces the susceptibility of particles to be entrained.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Engineering, Geological
Irene Redaelli, Claudio di Prisco, Francesco Calvetti
Summary: The study emphasizes the importance of assessing the time evolution of impact force exerted by dry flowing masses on rigid obstacles for dynamic design of sheltering structures and vulnerability evaluation of existing structures. A physically based force-time function is proposed to correlate local information with macroscopic response, providing insight into the impact process and factors influencing impact force-time evolution.
Article
Physics, Fluids & Plasmas
Swapnil Pravin, Brian Chang, Endao Han, Lionel London, Daniel Goldman, Heinrich M. Jaeger, S. Tonia Hsieh
Summary: The study investigated the force response of two parallel rods intruding into granular media, finding a peak in total work done by the intruders at a distance of approximately 3 particle diameters with more force chains forming at this gap spacing. Despite variations in friction, intruder size, and particle size, the peak total work of two parallel intruders remained consistent within a narrow range.
Article
Engineering, Geological
Bei Zhang, Yu Huang
Summary: The impact behavior of superspeed granular flows is crucial for barrier design, but lacks sufficient understanding. This study used centrifuge modeling and numerical modeling to investigate the energy consumption mechanism during granular flow impacts and proposed a static failure mode to estimate the action force. Additionally, it was found that reduced scale models under lower stress conditions may underestimate the impact force.
ENGINEERING GEOLOGY
(2022)
Article
Mechanics
Agata Widuch, Kari Myohanen, Markku Nikku, Marcin Nowak, Adam Klimanek, Wojciech Adamczyk
Summary: Efforts have been made to develop fast and reliable numerical models for modeling particulate flow due to its complexity. Reliable experimental data are essential for model development and validation. This study presents the design of a novel test-rig to visualize and measure particle flow patterns during collisions and provides valuable data sets for model validation.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Engineering, Chemical
Abhinesh Kumar, Prasanta Kumar Das
Summary: Based on experiments and DEM analysis, the collapse of a granular column confined in a vertical annulus is studied. The study reveals that during the collapse, there is an outward-moving avalanche and a unique shape of final deposit. In addition, an inward granular avalanche towards the center of the annulus is also observed in this study. The final deposit is categorized into four different cases based on the aspect ratio, and the shape of the deposit is mainly affected by the coefficient of friction and the removal speed of the confining walls.
Article
Engineering, Geological
Bei Zhang, Wenyang Li, Jian Pu, Yandong Bi, Yu Huang
Summary: In this study, the impact dynamics of dry granular flows under dilative and compressive Coriolis conditions were investigated using centrifuge modeling and the discrete element method (DEM). The results revealed that the influence of the Coriolis effect on granular impact is complex and difficult to determine in centrifuge modeling. It was found that the compressive Coriolis force had less significant influence when considering the total impact force on the barrier, while the impact under the dilative Coriolis condition was enhanced but closer to the results not affected by the Coriolis effect when focusing on the acting point of the resultant impact force on the barrier. Proper evaluation of the Coriolis effect and selection of appropriate Coriolis condition is recommended when conducting physical modeling tests using a centrifuge.
ENGINEERING GEOLOGY
(2023)
Review
Engineering, Chemical
Shahab Golshan, Reza Zarghami, Khashayar Saleh
Summary: This paper provides a comprehensive review of the flow of free-flowing particles inside silos, focusing on theoretical approaches for numerical simulation and modeling. The advantages and limitations of different simulation methods are discussed, along with the effects of various parameters on granular flow in silos. Finally, future research perspectives and main challenges in this area are highlighted.
REVIEWS IN CHEMICAL ENGINEERING
(2021)
Article
Engineering, Chemical
Jian Bai, Jian Li, Guangyang Hong, Jingwu Pan, Hongzhu Fei
Summary: The influence of spatial structure on the kinetic response of discrete soft matter is critical. In this study, the mesoscopic evolution and properties of ordered structures in dense granular flow under continuous shear were explored through experiments and simulations. It was found that the crystal structure of particles developed inward from the boundary and formed two morphological clusters. Continuous strain led to the evolution of chain-like polycrystalline to monocrystal structures within the cylindrical layers. The crystal symmetry between hexagonal close-packed and face-centered cubic was dynamically balanced in the flow, with hexagonal close-packed being more favored by the environment.
Article
Physics, Fluids & Plasmas
Damien P. Huet, Maziyar Jalaal, Rick van Beek, Devaraj van der Meer, Anthony Wachs
Summary: In granular mechanics, the shape of grains significantly influences the macroscopic properties of the system. The dynamics of granular collapses involve top-driven and buckling collapses, with the stability of the column being affected by the random initial configuration of the particle assembly.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Mechanics
Nhu H. T. Nguyen
Summary: By coupling the volume of fluid and discrete element method, this study investigates impulse waves generated by partially and fully submerged granular collapse. It finds that the relative submerged depth and inter-particle friction are the main factors affecting the maximum wave amplitude, proposing an empirical model and demonstrating its practical application in estimating the maximum wave amplitude of partially submerged landslide events.
Article
Acoustics
Xiao Siyou, Yang Junwei, Wei Zhongju
Summary: This study introduces the progresses in the estimation of the impact load of granular flow against a rigid wall. It reveals that the volume of granular flow is a key factor in determining the evolution of the impact load and proposes a simplified model to consider the relationship between multiple physical parameters.
SHOCK AND VIBRATION
(2022)
Article
Multidisciplinary Sciences
Yi Peng, Sheng Zhang, Jiangfeng Wan, Yangyang Yang, Kewei Tao, LiDong Ma, Guanghui Yang, Lei Yang, Mengke Wang
Summary: In order to solve the problem of particle clogging in slit funnels and maintain a stable discharge flow rate, a new funnel structure called the slit baffle funnel was proposed. Using the discrete element method (DEM), an investigation was conducted to study the impact of funnel half-angle theta, outlet width W, and baffle height H on flow rate and flow pattern. The results showed that this new funnel structure effectively prevented particle clogging and ensured a continuous and stable flow rate, even with a small outlet width. It was found that a higher flow rate could be achieved with a smaller funnel half-angle when H >3d. This new funnel structure has practical applications in industries such as mining, agriculture, food, and pharmaceuticals where granular matter clogging can occur in slit geometries.
Article
Environmental Sciences
Maryam Shademani, Bruno Blais, Ahmad Shakibaeinia
Summary: Sub-aerial (dry) and submerged dense granular collapses were studied using a CFD-DEM numerical model, with physical experiments for validation. The study showed good compatibility between numerical and experimental results, analyzed collapse mechanisms, post-collapse morphological parameters, and solid volume fraction variation. It was found that the aspect ratio of the granular column is a key factor in determining granular morphology under submerged and dry conditions.
Article
Mechanics
L. Chupin, T. Dubois, M. Phan, O. Roche
Summary: This study presents numerical simulations of the collapse of glass bead columns with different aspect ratios using a new two-phase bi-projection scheme, and compares the results with experiments. The granular flow is modeled using a viscoplastic rheology based on the mu(I)-rheology, resulting in a Drucker-Prager plasticity criterion. The study also investigates the sensitivity of results to resolution and basal friction coefficient.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2021)
Article
Mechanics
Tijan Mede, Guillaume Chambon, Francois Nicot, Pascal Hagenmuller
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2020)
Article
Water Resources
Eduard Puig Montella, Chao Yuan, Bruno Chareyre, Antonio Gens
ADVANCES IN WATER RESOURCES
(2020)
Article
Engineering, Geological
Franck Bourrier, David Toe, Bruna Garcia, Julien Baroth, Stephane Lambert
Summary: Rockfall propagation models are commonly used for assessing rockfall hazard quantitatively. However, their capacities and limitations are difficult to assess due to limited experimental data at the slope scale. This article presents experiments conducted in a quarry in France, showing the significant influence of topography on block propagation.
Article
Engineering, Geological
Stephane Lambert, David Toe, Alessio Mentani, Franck Bourrier
Summary: This article proposes a procedure for developing tools to quantify the on-site efficiency of any rockfall barrier using meta-modeling techniques. The study shows that the efficiency of the barrier is highly site-dependent, with significant differences in real situations.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Engineering, Geological
Hao Xiong, Zhen-Yu Yin, Francois Nicot, Antoine Wautier, Miot Marie, Felix Darve, Guillaume Veylon, Pierre Philippe
Summary: This paper introduces a novel multi-scale approach for modelling granular column collapse, utilizing a micro-mechanical model and SPH method to successfully simulate the flow of granular column under low water content conditions. The numerical results show good agreement with experimental observations and capture meso-scale behavior.
Article
Engineering, Geological
Chao Yuan, Bruno Chareyre
Summary: This study combines the pendular model with the two-phase pore-scale finite volumes (2PFV) method for the first time to simulate complete drainage in partially saturated granular soils. The contribution of pendular bridges to water retention and induced internal stress is examined.
Article
Materials Science, Multidisciplinary
A. Clerc, A. Wautier, S. Bonelli, F. Nicot
Summary: Granular materials exhibit complex collective behavior resulting from dynamic rearrangements in the micro-structure, where local changes in density lead to jamming or unjamming. This paper investigates instabilities in the form of localized bursts of kinetic energy at both micro and meso scales.
Article
Engineering, Geological
Agathe Furet, Pascal Villard, Jean-Philippe Jarrin, Stephane Lambert
Summary: This study investigates an innovative protection structure for gravity-driven natural hazards, such as landslides, consisting of a vertical wall made of interconnected concrete blocks. The structure offers advantages of reduced space requirements, versatility, and easy maintenance. The study examines the response of the structure under impact using real-scale experiments and numerical simulations. The results show that the numerical model effectively simulates the deformation and time evolution of the structure's impact response.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Mechanics
Jiaying Liu, Antoine Wautier, Francois Nicot, Felix Darve, Wei Zhou
Summary: The shear chain concept is used in this study to investigate shear characteristics in granular materials at different scales and to explore the correlations between microscopic and macroscopic shear behaviors. The results show that the orientation of shear bands is influenced by the sample aspect ratio, while the orientation of shear chains only depends on the stress state. It is conjectured that shear bands are formed by a collection of crossing shear chains at the meso scale.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Engineering, Civil
Stephane Lambert, Franck Bourrier, Ana-Rocio Ceron-Mayo, Loic Dugelas, Fabien Dubois, Guillaume Piton
Summary: This article addresses the challenge of modeling small-scale flexible barriers and proposes similitude criteria based on flow velocity, barrier geometry, and mechanical properties. Numerical simulations and flume experiments are conducted to validate these criteria and assess the importance of considering the mechanical characteristics of the barrier components. The results demonstrate the feasibility of this approach and compare deformations under different loading conditions.
JOURNAL OF HYDRAULIC ENGINEERING
(2023)
Article
Engineering, Civil
Guillaume Piton, Ana Rocio Ceron Mayo, Stephane Lambert
Summary: This paper presents a comprehensive analysis of the interactions between large wood (LW) and flexible barriers using small scale models. It proposes a dimensionless criterion to compute blockage probability of single logs and provides an equation to compute flow depth at a barrier accounting for head losses related to large numbers of logs. The study also investigates the conditions leading to the release of LW when the barrier is overwhelmed. The results show that flexible barriers are effective in trapping LW.
JOURNAL OF HYDRAULIC ENGINEERING
(2023)
Article
Mathematics, Applied
Jean Lerbet, Noel Challamel, Francois Nicot, Felix Darve
Summary: This paper presents an explicit and coordinate-free formulation of incremental discrete mechanics in potentially non-integrable hypoelasticity. It develops a general framework that treats hypoelasticity as an Ehresmann connection on the cotangent bundle T*M, distinguishing between weak or integrable incremental evolutions and strong or non-integrable incremental evolutions based on the nature of the hypoelastic constitutive law. The geometric structure of the double tangent bundle TT*M is utilized to obtain the geometric counterpart kappa of the tangent stiffness matrix. The validity of the incremental evolution is established under specific conditions in TT*M, and a four-grains hypoelastic granular system is used to illustrate the general results in detail.
ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK
(2023)
Article
Engineering, Civil
Stephane Lambert, Firmin Fontaine, Guillaume Piton
Summary: Flexible barriers have shown promise in trapping woody debris to prevent it from reaching hazardous areas. Small-scale experiments have been conducted to investigate the interaction between the flow and the barrier, with a focus on the influence of various parameters on the loading experienced by the barrier. The findings highlight the complexity of the relationship between the barrier loading and the characteristics of the trapped logs and accumulation.
EUROPEAN JOURNAL OF ENVIRONMENTAL AND CIVIL ENGINEERING
(2023)
Article
Engineering, Civil
Ritesh Gupta, Franck Bourrier, Vincent Acary, Stephane Lambert
Summary: This article presents the development and calibration of a numerical model simulating the response of a novel rockfall protection structure. The model is calibrated using real-scale experiments and Bayesian interface statistical learning method. The calibrated model accurately predicts the dynamic response of the experimental structure.
ENGINEERING STRUCTURES
(2023)
Article
Mechanics
E. P. Montella, J. Chauchat, B. Chareyre, C. Bonamy, T. J. Hsu
Summary: The behavior of underwater granular avalanches depends on the initial volume fraction, with loose granular beds triggering avalanches almost instantaneously and densely packed beds delaying flow. A new continuum model incorporates granular dilatancy as a normal stress, providing insights into the different behaviors of loose and dense avalanches. The model successfully explains the interaction between granular stress and fluid pressure in avalanche dynamics.
JOURNAL OF FLUID MECHANICS
(2021)
