scholarly journals MPM hydro-mechanical modelling of flows impacting rigid walls

2021 ◽  
Author(s):  
Sabatino Cuomo ◽  
Angela Di Perna ◽  
Mario Martinelli
Keyword(s):  
Rigid Wall ◽  
Material Point ◽  
Complex Processes ◽  
Dry Granular Flow ◽  
Propagation Pattern ◽  
Open Issue ◽  
Complex Propagation ◽  
Rigid Walls ◽  
The Impact ◽  
Fluid Interaction

The study on impact mechanisms of flow-like landslides against structures is still an open issue in the scientific literature. Many researchers have employed so far either experiments or numerical methods, but the evaluation of the impact forces on mitigation obstacles remains difficult especially if the solid-fluid interaction within the flow is considered. This study shows how advanced numerical tools, such as Material Point Method, may be used in simulating those complex processes. The simulations are carried out for two well documented laboratory tests: a dry granular flow impacting a rigid wall under different geometries and testing conditions in a small-scaled flume and a saturated flow with complex propagation pattern in a centrifuge apparatus. The numerical modelling is validated against the observations and then used to explore the response of different flows impacting rigid structures in other conditions than in the experiments. The soil-fluid interaction influences the type of impact mechanism, the kinematics of the flow, and the space-time trend of the impact pressure against the structure.

scholarly journals Impact Forces and Energy of Flow-like Landslides Against Protection Barriers: a New MPM-validated Empirical Formulation

2022 ◽  
Author(s):  
Angela Di Perna ◽  
Sabatino Cuomo ◽  
Mario Martinelli
Keyword(s):  
Interaction Mechanism ◽  
Empirical Method ◽  
Material Point ◽  
Rigid Barrier ◽  
Impact Forces ◽  
Field Evidence ◽  
Landslide Body ◽  
Open Issue ◽  
Hydromechanical Behaviour ◽  
The Impact

Abstract Full understanding the interaction mechanisms between flow-like landslides and the impacted protection structures is an open issue. In fact, while researchers have used several approaches, from experimental to numerical, it is true that the adequate assessment of the hydromechanical behaviour of the landslide body requires both a multiphase and large deformation approach.This paper firstly proposes a conceptual framework for a specific type of protection structure, namely a rigid barrier fixed to the base ground. Two different approaches are proposed: i) an advanced hydro-mechanical numerical model based on Material Point Method is tested in simulating the whole complex landslide-structure-interaction mechanism(s), ii) a more simplified empirical model is casted to estimate the impact force and the time evolution of kinetic energy. The calibration and validation of the empirical formulation are pursued, respectively, based on the MPM numerical results, and referring to a large dataset of field evidence for the peak impact pressure. Finally, the performance of the newly proposed empirical method is compared to the methods available in the literature and its advantages are outlined.

scholarly journals Dam Breach Simulation with the Material Point Method

Computation ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 8
Author(s):  
Chendi Cao ◽  
Mitchell Neilsen
Keyword(s):  
Material Point Method ◽  
Mixture Theory ◽  
Material Point ◽  
Point Method ◽  
Internal Erosion ◽  
Dam Breach ◽  
New Model ◽  
Hencky Strain ◽  
The Impact ◽  
Soil And Water

Dam embankment breaches caused by overtopping or internal erosion can impact both life and property downstream. It is important to accurately predict the amount of erosion, peak discharge, and the resulting downstream flow. This paper presents a new model based on the material point method to simulate soil and water interaction and predict failure rate parameters. The model assumes that the dam consists of a homogeneous embankment constructed with cohesive soil, and water inflow is defined by a hydrograph using other readily available reach routing software. The model uses continuum mixture theory to describe each phase where each species individually obeys the conservation of mass and momentum. A two-grid material point method is used to discretize the governing equations. The Drucker–Prager plastic flow model, combined with a Hencky strain-based hyperelasticity model, is used to compute soil stress. Water is modeled as a weakly compressible fluid. Analysis of the model demonstrates the efficacy of our approach for existing examples of overtopping dam breach, dam failures, and collisions. Simulation results from our model are compared with a physical-based breach model, WinDAM C. The new model can capture water and soil interaction at a finer granularity than WinDAM C. The new model gradually removes the granular material during the breach process. The impact of material properties on the dam breach process is also analyzed.

Geological and geomorphological problems caused by transportation and industry

2011 ◽  
Vol 3 (3) ◽  
Author(s):  
Lorant David ◽  
Zoltan Ilyes ◽  
Zoltan Baros
Keyword(s):  
Fly Ash ◽  
Industrial Development ◽  
Transport Infrastructure ◽  
Narrow Strip ◽  
Complex Processes ◽  
Shopping Centres ◽  
Industrial Parks ◽  
Surface Sealing ◽  
Steep Slopes ◽  
The Impact

AbstractAlterations in topography due to the construction of transport infrastructure and industrial development are the results of rather complex processes. The impact of transport constructions upsetting (topographic) equilibrium is manifested in a relatively narrow strip, and, mostly, through producing abnormally steep slopes, in reducing relief stability. The earthworks for transport routes are themselves also landscape-forming factors whereas in the case of industrial developments, planation is usually mentioned. Topographic changes related to the construction of transport infrastructure and industrial development are discussed historically in this chapter. Among the direct impacts of the first are those related to the construction of Roman and Medieval roads, hollow roads in loess, public roads, motorways, railways, canals, tunnels and airports; while of the second are those of early mining and metallurgy, cellars, sludge reservoirs, slag cones and fly-ash reservoirs, cooling ponds, industrial parks, shopping centres and waste disposal sites. Of the indirect ones, an introduction is given to impacts of surface sealing, changes in runoff, the ‘waterfall effect,’ as well as to environmental impacts under permafrost conditions.

Numerical Simulation on Concrete Median Barrier for Reducing Concrete Fragment Under Harsh Impact Loading of a 25-ton Truck

2017 ◽  
Vol 139 (2) ◽  
Author(s):  
Jaeha Lee ◽  
Goangseup Zi ◽  
Ilkeun Lee ◽  
Yoseok Jeong ◽  
Kyeongjin Kim ◽  
...  
Keyword(s):  
Impact Loading ◽  
Traffic Accident ◽  
Impact Analysis ◽  
Threshold Value ◽  
Rigid Wall ◽  
Wire Mesh ◽  
Element Size ◽  
Preliminary Study ◽  
The Impact ◽  
Controlling Behaviors

Recently, there was a collision accident involving vehicle–concrete median barrier in South Korea, and unfortunately, passengers on the opposite direction road were killed by the flying broken pieces of concrete generated by the collision. Primarily after this accident, we felt the need for developing an improved concrete median barrier up to level of SB6 impact severity in order to minimize the amount of broken pieces of concrete and any possibility of traffic accident casualty under the impact loading of truck. Accordingly, in this study, several designs of concrete median barriers have been examined, and a preliminary study has been conducted for developing and verifying appropriate collision model. First, type of vehicle was selected based on impact analysis on rigid wall. Then, the effects of element size and other key parameters on the capacity of the concrete median barrier under impact were studied. It was found that the key parameters for controlling behaviors of the median barrier under impact loading were contact option, threshold value, and mesh and boundary conditions. Furthermore, as a parametric study, effect of geometry and amount of wire-mesh or steel rebar in concrete median barrier on impact resistances of median barrier for reducing the collision debris were investigated. The amount of volume loss after the collision of truck was compared for various reinforcement ratios.

scholarly journals Evaluation of the Impact Force of Dry Granular Flow onto Rock Shed

2019 ◽  
Vol 07 (05) ◽  
pp. 1-15
Author(s):  
Chun Liu ◽  
Zhixiang Yu ◽  
Junfei Huang
Keyword(s):  
Granular Flow ◽  
Impact Force ◽  
Dry Granular Flow ◽  
The Impact

A mixed contact model for an immersed collision between two solid surfaces

2008 ◽  
Vol 366 (1873) ◽  
pp. 2205-2218 ◽  
Author(s):  
Fu-Ling Yang ◽  
Melany L Hunt
Keyword(s):  
Surface Deformation ◽  
Elastohydrodynamic Lubrication ◽  
Solid Particles ◽  
Solid Surfaces ◽  
Additional Energy ◽  
Collision Model ◽  
Dry Granular Flow ◽  
Wide Range ◽  
The Impact ◽  
Surrounding Liquid

Experimental evidence shows that the presence of an ambient liquid can greatly modify the collision process between two solid surfaces. Interactions between the solid surfaces and the surrounding liquid result in energy dissipation at the particle level, which leads to solid–liquid mixture rheology deviating from dry granular flow behaviour. The present work investigates how the surrounding liquid modifies the impact and rebound of solid spheres. Existing collision models use elastohydrodynamic lubrication (EHL) theory to address the surface deformation under the developing lubrication pressure, thereby coupling the motion of the liquid and solid. With EHL theory, idealized smooth particles are made to rebound from a lubrication film. Modified EHL models, however, allow particles to rebound from mutual contacts of surface asperities, assuming negligible liquid effects. In this work, a new contact mechanism, ‘mixed contact’, is formulated, which considers the interplay between the asperities and the interstitial liquid as part of a hybrid rebound scheme. A recovery factor is further proposed to characterize the additional energy loss due to asperity–liquid interactions. The resulting collision model is evaluated through comparisons with experimental data, exhibiting a better performance than the existing models. In addition to the three non-dimensional numbers that result from the EHL analysis—the wet coefficient of restitution, the particle Stokes number and the elasticity parameter—a fourth parameter is introduced to correlate particle impact momentum to the EHL deformation impulse. This generalized collision model covers a wide range of impact conditions and could be employed in numerical codes to simulate the bulk motion of solid particles with non-negligible liquid effects.

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