Article
Engineering, Geological
Charles W. W. Ng, Dingchen Zhang, Clarence E. Choi, Haiming Liu, Raymond C. H. Koo, Rui Chen
Summary: Debris flow is a common geological hazard in mountainous areas, and large boulders carried by debris flow can cause significant damage to downstream facilities. Constructing steel baffles with footings on steep slopes is a cost-effective method to dissipate the impact energy of boulders. However, the current design of steel baffles and their footings is often based on empirical knowledge, which may limit their effectiveness in resisting boulder impact.
ENGINEERING GEOLOGY
(2023)
Article
Engineering, Aerospace
Erkai Watson, Jose-Luis Sandoval Murillo, Markus Buettner, Pascal Matura, Martin Schimmerohn
Summary: We present new developments to a discrete element model designed to simulate hypervelocity impacts between on-orbit satellites and space debris. The model accurately captures the fragmentation process of impact events and has been enhanced to improve its behavior at lower velocities. By enhancing the model's bonding structure, it can more accurately simulate a continuum material. The results show that the model is capable of capturing the full range of fragment sizes.
Article
Engineering, Chemical
Z. Bibak, S. Banisi
Summary: The study investigated the dynamics of non-spherical particles compared to spherical particles using a combination of physical and DEM modeling approaches. The simulation results showed significant differences in particle movement, structure, and participation in high energy impact actions between cubical and spherical particles. The computation time of the simulation increased by 35 times when particles changed from spherical to cubical shape.
ADVANCED POWDER TECHNOLOGY
(2021)
Article
Computer Science, Interdisciplinary Applications
Songkai Ren, Pei Zhang, Teng Man, S. A. Galindo-Torres
Summary: Rapid soil-boulder mixed flow in steep mountainous regions can cause damage to critical infrastructures. Baffles are commonly used to mitigate the destructive power of this natural hazard. However, the influence of particle size difference, especially boulders, has often been overlooked. Therefore, numerical simulations were conducted to investigate the effects of boulders using a Discrete Element Material Point Method. The results show that collisions and interactions between different components dissipate kinetic energy and reassemble the spatial distribution of soils and boulders, highlighting the importance of considering boulders in designing optimal baffles.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Engineering, Marine
Yan Xiong, Qiuhua Liang, Jinhai Zheng, Jacob Stolle, Ioan Nistor, Gang Wang
Summary: Many post-event field investigations have shown that the dynamics of floodwaters and large floating objects have a significant impact on building damage during a tsunami event. However, the interactions between flood waves, floating debris, and structures have not been thoroughly explored or understood, and there are few modeling tools available, especially for multiple debris. This paper introduces a novel coupled modeling system that combines a high-performance 2D hydrodynamic model with a 3D discrete element method (DEM) model to simulate the movement of multiple debris and quantify the impact forces on structures.
Article
Geosciences, Multidisciplinary
Jian Pu, Yu Huang, Zhen Guo, Yandong Bi, Chong Xu, Xingyue Li, Zhiyi Chen
Summary: A vulnerability assessment framework for a two-story RC building based on the GF-discrepancy point selection strategy and DEM-FEM is proposed, which can reflect the failure characteristics of RC buildings under mass flow impact.
Article
Nuclear Science & Technology
Sheng Cao, Bin Zhang, Wenpeng Wang, Jianqiang Shan
Summary: This study uses numerical simulation to explore the influencing mechanism of the structural design of the core catcher on the shape of the debris bed, and finds that secondary scattering plays a significantly positive role in enhancing the uniformity of the debris bed. The study lays a foundation for the analysis and evaluation of the heat transfer performance and long-term decay heat removal of the debris bed, and provides engineering guidance for the design and optimization of the sodium cooled fast reactor core catcher.
NUCLEAR ENGINEERING AND DESIGN
(2023)
Article
Mathematics, Interdisciplinary Applications
Thanh-Trung Vo, Cuong T. Nguyen, Trung-Kien Nguyen, Van My Nguyen, Thi Lo Vu
Summary: The study investigates the impact dynamics of wet agglomerates composed of primary spherical particles. Findings indicate that the mechanical strength, deformation, and connectivity of the agglomerate strongly depend on key parameters. Additionally, the early-stage strength and final-stage deposition height of the agglomerate behave as a function of the Capillary-Stokes inertial number, revealing a relationship between rheological properties, liquid properties, and impact conditions.
COMPUTATIONAL PARTICLE MECHANICS
(2022)
Article
Construction & Building Technology
Lin Wu, Xiedong Zhang, Fuming Kuang, Wei Wang, Hong Guo
Summary: This study compares the vibration mitigation effects of steel plate, concrete zone, and double liner on tunnels and adjacent tunnels during train vibration, and finds that the concrete zone has the best vibration isolation effect.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Engineering, Chemical
Daniel Schulz, Nadja Woschny, Eberhard Schmidt, Harald Kruggel-Emden
Summary: This study investigates the detachment of fine adhered dust particles during bulk particle contacts using an adhesive Discrete Element Method (DEM). The research introduces dust detachment functions in a non-adhesive DEM, which track only the coarse carrier particles as a composed bulk particle. The implemented detachment functions, including normal and tangential lift-off conditions, as well as a rotational condition, are benchmarked based on dust-resolved adhesive DEM simulations.
Article
Engineering, Geological
Jian Guo, Yifei Cui, Wenjie Xu, Yanzhou Yin, Yao Li, Wen Jin
Summary: This study used the discrete element method to analyze the dynamic processes of a debris flow event in Dujiangyan city, China. The results showed two different scenarios of rock slide and bed entrainment, as well as the transformation of landslide to debris flow during short-term blockage.
Article
Engineering, Chemical
T. Osborne, D. Rhymer, D. Werner, A. Ingram, C. R. K. Windows-Yule
Summary: In this study, the effect of pin number and projected area on the grinding performance of stirred mills was investigated using the Discrete Element Method. Results showed that increasing the number of pins improved grinding efficiency, but it also increased power consumption. However, maintaining the same projected area led to less variation in performance, indicating that the specific configuration of the pins may not be as crucial.
Article
Engineering, Geological
Charles W. W. Ng, Haiming Liu, Clarence E. Choi, Julian S. H. Kwan, W. K. Pun
Summary: In this study, physical tests were conducted to investigate the impact dynamics of debris flows with and without boulders on a rigid barrier. Contrary to current design practices, it was found that the debris provided a cushioning effect to attenuate the impact force of the boulders. The interaction between debris flow and boulders during the impact process was observed to have a significant influence on reducing the impact load.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2021)
Article
Engineering, Mechanical
Zhaohui Chong, Tenglong Yue, Qiangling Yao, Xuehua Li, Chuangkai Zheng, Ze Xia, Huaizhen Li
Summary: Experimental and numerical results are consistent, showing that increasing the anchorage length improves the strength and bondability of the system, restrains debonding, and facilitates crack conversion, but is still primarily affected by the resin's shear cracks.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Mathematics, Interdisciplinary Applications
G. Casas, I de-Pouplana, R. Gandikota, E. Onate
Summary: A numerical technique based on CFD-DEM method is proposed for analyzing particle impact drilling (PID) systems. This method combines finite element method and discrete element method to handle the fluid and particle phases respectively. The implementation issues and validity of simplifying assumptions are discussed. The potential and limitations of the proposed method are demonstrated through simulations on industrial designs.
COMPUTATIONAL PARTICLE MECHANICS
(2022)
Article
Engineering, Geological
C. E. Choi, C. W. W. Ng, S. R. Goodwin, L. H. D. Liu, W. W. Cheung
CANADIAN GEOTECHNICAL JOURNAL
(2016)
Article
Engineering, Geological
C. W. W. Ng, C. E. Choi, S. R. Goodwin, W. W. Cheung
Article
Engineering, Geological
C. W. W. Ng, C. E. Choi, R. C. H. Koo, S. R. Goodwin, D. Song, J. S. H. Kwan
Article
Engineering, Geological
R. C. H. Koo, J. S. H. Kwan, C. Lam, S. R. Goodwin, C. E. Choi, C. W. W. Ng, J. Yiu, K. K. S. Ho, W. K. Pun
CANADIAN GEOTECHNICAL JOURNAL
(2018)
Article
Engineering, Geological
C. W. W. Ng, C. E. Choi, S. R. Goodwin
CANADIAN GEOTECHNICAL JOURNAL
(2019)
Article
Engineering, Geological
A. Leonardi, S. R. Goodwin, M. Pirulli
Article
Computer Science, Interdisciplinary Applications
S. R. Goodwin, C. E. Choi
COMPUTERS AND GEOTECHNICS
(2020)
Article
Engineering, Geological
S. R. Goodwin, C. E. Choi, C-Y Yune
Summary: Baffle arrays are effective in reducing impact load from boulders in granular flows, with a recommended spacing ratio of 1 < s/delta < 4. A staggered array with three rows of baffles on a horizontal plane is the optimal configuration for peak discharge reduction by up to four times.
CANADIAN GEOTECHNICAL JOURNAL
(2021)
Article
Computer Science, Interdisciplinary Applications
C. E. Choi, S. R. Goodwin
COMPUTERS AND GEOTECHNICS
(2020)
Article
Engineering, Geological
C. E. Choi, S. R. Goodwin
Summary: Increasing the number of grains per unit depth can suppress flow dispersion, making small-scale flows on smooth beds resemble large-scale flows on roughened beds. Rough beds can reduce peak bulk density by up to 15% compared to smooth beds. The DMM underestimates flow depths by 90% at the flow front because it cannot consider density changes or vertical momentum.
CANADIAN GEOTECHNICAL JOURNAL
(2021)
Article
Computer Science, Interdisciplinary Applications
Saoirse Robin Goodwin, Clarence Edward Choi
Summary: This study investigates the impact of debris flows on barriers through experiments and numerical simulations, providing insights on how different material volumes and water velocities can affect engineering design.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Geosciences, Multidisciplinary
Guillaume Piton, Saoirse Robin Goodwin, Emily Mark, Alex Strouth
Summary: This study presents a new numerical framework for understanding and designing the long-term behavior of boulder-laden flows. The framework combines hydraulic equations, criteria for predicting boulder blockages, and simple statistical methods to quickly evaluate interactions between low- and high-risk flows. The framework can be applied to debris flows in canyons and engineered structures.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Proceedings Paper
Engineering, Geological
George R. Goodwin, Clarence E. Choi, Charles W. W. Ng, W. W. Cheung
GEOTECHNICAL FRONTIERS 2017: WALLS AND SLOPES
(2017)
Article
Engineering, Geological
C. E. Choi, S. R. Goodwin, C. W. W. Ng, D. K. H. Cheung, J. S. H. Kwan, W. K. Pun
GEOTECHNIQUE LETTERS
(2016)
