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Research paper thumbnail of Pore-scale study of permeability and tortuosity for flow through particulate media using virtual approach

In this paper, Lattice Boltzmann method (LBM) has been used to study the effects of permeability ... more In this paper, Lattice Boltzmann method (LBM) has been used to study the effects of permeability and tortuosity on flow through saturated particulate media and identify the relationships between permeability and tortuosity with other parameters such as particles diameter, grain specific surface, and porosity. LBM is a simple kinematic model that can incorporate the essential physics of microscopic and mesoscopic processes involved in flow through granular soils. The obtained results indicate that the 2D LB model, due to its inherent theoretical advantages, is capable of demonstrating that the porosity and specific surface are the most influential parameters in determining the intrinsic permeability of granular media. The obtained results show that particles' size diameter has a twofold effect on the coefficient of permeability: one is through specific surface and the other is by tortuosity factor. Numerical study also reveals that tortuosity of granular soils decreases almost linearly with increasing the porosity.

Research paper thumbnail of Parallel algorithm for fractal model of creation of soil structure using particles-size distributions

Journal of physics, Oct 15, 2012

View the article online for updates and enhancements. You may also like Simulation of wave impact... more View the article online for updates and enhancements. You may also like Simulation of wave impact on shore protection structures using 3D model of wave processes S V Protsenko-The condition assessment scheme for ancient timber structure using material and deformation analysis W Juan and A D Putri-A Comparative Analysis on the Methods of Strengthening Isolated Reinforced Concrete Columns Mungur Ved Vritesh and Seeboo Asish

Research paper thumbnail of Toward the prediction of rheological properties of self-consolidating concrete as diphasic material

Construction and Building Materials, 2019

The relationship between SCC and its corresponding suspending phase was evaluated. The rheologica... more The relationship between SCC and its corresponding suspending phase was evaluated. The rheological properties of sieved and modified mortars are well correlated. The VP/VS, W/B, and suspending phase affect the intrinsic viscosity. The proposed modified models were extended to predict rheological properties.

Research paper thumbnail of Finite volume analysis of reinforced concrete structure cracking using a thermo-plastic-damage model

This paper proposes modifications to the phenomenological model formulation called CDPM2 develope... more This paper proposes modifications to the phenomenological model formulation called CDPM2 developed by Grassl et al. (2013). The proposed modifications are designed to enhance model performance with coupling to temperature effects. A very strong coupling between nonlinear elasticity, plasticity, nonlocal damage evolution and temperature gradient is used to simulate arbitrary crack propagation. The use of FVM to model solid damage is a numerical challenge. This approach presents some advantages such as: ensuring that discretization is conservative even when the geometry is changing; providing a simple formulation that can be obtained directly from a difference method; and employing unstructured meshes. Most authors have neglected the nonlinearity of concrete in the elastic domain from the start of loading to the plastic domain. In this paper we confirm that concrete rheology is not linear even under low loading. Also, since the so-called fracture energy is a key parameter needed to determine crack size and how they propagate in space, we consider that the fracture energy is both material and geometrical parameter dependent. For this reason, we developed a new approach which includes adaptive mesh, nonlinear rheology and thermal effects to recalculate fracture energy at each time step. Many authors use a constant value obtained from experiments to calculate fracture energy, others use a numerical correlation. In this study, the fracture energy parameter is not constant and can vary with temperature or/and with a change in geometry due to concrete failure. As is well known, mesh quality of complex geometries is very important for determining accurate predictions. A new meshing tool was developed using the C ++ programming language. This tool is faster, more accurate and produces a high quality structured mesh. The predictions obtained were compared to a wide variety of experimental data and showed good agreement.

Research paper thumbnail of Small strain stiffness and stiffness degradation curve of sensitive Champlain clay

Research paper thumbnail of Validation of strain/energy-based pore pressure model in one-dimensional response analyses using centrifuge tests

Soil Dynamics and Earthquake Engineering

Research paper thumbnail of 2-D Pore-Particle Scale Model of the Erosion at the Boundary of Two Soils under Horizontal Groundwater Flow

Scour and Erosion, 2010

Modeling particle-fluid systems in porous media encountered in many scientific and engineering ap... more Modeling particle-fluid systems in porous media encountered in many scientific and engineering applications presents a significant challenge. This paper outlines a hydrodynamic flow at a low Reynolds number through saturated porous media which is generated virtually using only the grain-size distribution curves of soils. In order to represent the pore and granular structures of soils, a novel model was developed using a fractal approach. For a given porosity, particle and pore size distributions were successfully modeled for a wide range of soils. We tested the model ' s conductivity behaviour by carrying out a steady-state flow through a fractal structure. Soil particle movement was modeled using the discrete element method (DEM), and the hydrodynamic flow was simulated by the well-known marker-andcells (MAC) method, with special conditions imposed at the particle boundaries. The fluid-particle interaction was taken into account in our calculations using the method of direct force integration at the surface of particles. Several comparisons of our numerical results to those of published experiments for particle-particle and particlewall interaction in a viscous fluid show very good agreement. Finally, an example of a possible erosion scenario at the interface of two different soils under a horizontal flow is presented. The results and a discussion of this model ' s applicability are also presented. This study is a part of an extensive program which includes 3-D simulations aimed at gaining a better understanding erosion phenomena in soils made up of irregularly shaped particles under hydrodynamic flow.

Research paper thumbnail of Inspection of the lids of shallowly buried concrete structures based on the propagation of surface waves- PART II

Journal of Applied Geophysics, 2018

The inspection of underground concrete utility structures can be a challenging task due to their ... more The inspection of underground concrete utility structures can be a challenging task due to their inaccessibility. This article presents a nondestructive inspection technique for the lids of such structures based on the propagation of elastic waves where the variation in soil vertical acceleration following an impact is recorded along a given line at the surface of the soil. The structures investigated are made of reinforced concrete and are located below a shallow homogeneous soil layer which is covered by a pavement. It is shown through finite difference numerical modeling that elastic waves are affected by the state of degradation of the underground concrete structure. It is also shown that the difference in dynamic properties between the soil and the concrete structure causes the latter to act as a waveguide that affects the variation of the vertical acceleration measured at the surface of the model. The propagation of elastic waves within different underground profiles is studied in terms of the variation of their energy and of their group and phase velocity. Theoretical models, computed using the propagator matrix technique, are presented in the appendix to demonstrate the importance of the waveguide effects, caused by the presence of the concrete structure, on the group and phase velocity dispersion curves of Rayleigh waves. Finally, some of the results obtained from the inspection of two different real underground structures are also presented. These results show that the proposed inspection technique, developed based on 1D and 2D numerical testing, is also effective for real structures.

Research paper thumbnail of Virtual Approach to Simulating Geotechnical Problems under Both Static and Dynamic Conditions

World Academy of Science, Engineering and Technology, International Journal of Geotechnical and Geological Engineering, 2017

Research paper thumbnail of 3D Virtual Laborato Ry for Geotechnical Applications: Another Perspective

Research paper thumbnail of Numerical Modeling of Water Transport in Ultra-High-Performance Fiber-Reinforced Concrete

Rilem bookseries, Jul 1, 2022

Research paper thumbnail of Laboratory Measurement of Permeability in Postseismic Flow

International Journal of Geomechanics

Research paper thumbnail of Virtual reality 3d simulation of fluide-particle interaction

COUPLED V : proceedings of the V International Conference on Computational Methods for Coupled Problems in Science and Engineering :, 2013

Research paper thumbnail of A More Comprehensive Modeling of Contact Force During Shear Testing Using Dem

Proceedings of the VII European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS Congress 2016), 2016

Research paper thumbnail of Strain rate effect on static and dynamic behaviors of eastern Canada fine-grained soils

Canadian Geotechnical Journal, 2021

The assessment of the strain rate effect on the geotechnical properties of soils constitutes an i... more The assessment of the strain rate effect on the geotechnical properties of soils constitutes an important step toward a more accurate analysis of their response. This study presents the experimental results of monotonic and cyclic simple shear tests performed to examine the strain rate ([Formula: see text]) effect on the behavior of eastern Canada soils. Nine natural soils sampled from different locations in eastern Canada were used in this study. The tests were performed on a simple shear device using a strain-controlled mode. In addition to the obtained experimental results, published data in the literature were used to draw the conclusions of this study. Analysis of the data indicates that the undrained shear strength (τf) increases proportionally with the strain rate by approximately 6%–17% per log cycle of [Formula: see text]. The results also show that the secant shear modulus G increases with the strain rate, especially at large strain amplitudes. Moreover, the analysis of th...

Research paper thumbnail of Experimental and numerical investigation of the Saint-Adelphe landslide after the 1988 Saguenay earthquake

Canadian Geotechnical Journal, 2020

On 25 November 1988, after the Saguenay earthquake, a landslide occurred in the municipality of S... more On 25 November 1988, after the Saguenay earthquake, a landslide occurred in the municipality of Saint-Adelphe. The soil profile indicated that the deposit was composed of a stiff clay crustal layer overlying sensitive plastic clay with a soft-to-stiff consistency. A geotechnical investigation was carried out in situ and in the laboratory and included the use of a new seismic simulator to develop a geotechnical model of the Saint-Adelphe clay. The model was incorporated in a finite-difference slope stability analysis before and during the earthquake. The results showed the development of plastic zones and the generation of pore water pressure, but the global safety factor remained above unity. A post-seismic analysis that utilized a strain-softening behavior model showed the initiation and propagation of the plastic zone, as well as the development of a failure surface close to the observed failure surface. Therefore, it is proposed that the Saint-Adelphe landslide could be explained...

Research paper thumbnail of New Model of Shear Modulus Degradation and Damping Ratio curves for Sensitive Canadian Clays

Canadian Geotechnical Journal

This study investigated a new predictive model of the shear modulus reduction () and damping rati... more This study investigated a new predictive model of the shear modulus reduction () and damping ratio () curves for sensitive eastern Canada clays. The model was established based on experimental measurements of and performed on 69 sensitive clay specimens from eastern Canada. The compiled database was first analyzed to qualitatively assess the influences of different soil parameters on the measurements. Next, statistical analyses using regression analysis and the modified hyperbolic model were performed. It was found that the and values of sensitive eastern Canada clays were influenced mainly by the plasticity index (Ip), mean effective stress , and structure, which was quantified by the liquidity index (IL). Based on the statistical analysis performed, new equations for and were proposed. The newly proposed model was compared with previously published models. The comparison clearly showed that the proposed model was more representative of sensitive eastern Canada clays. Consequently,...

Research paper thumbnail of Porous Stones in Permeability Measurement: Drawbacks and Solution

Canadian Geotechnical Journal

Porous stones are commonly used in geotechnical laboratory testing to provide solid support at th... more Porous stones are commonly used in geotechnical laboratory testing to provide solid support at the two ends of the tested specimen. Although porous stones can have several advantages, they can induce a hydraulic impedance that might alter the flowrate results. Numerous suggestions and recommendations were issued to avoid some of the problems encountered when using porous stones, such as clogging and stones' low permeability coefficient (Kp). However, it is proven in this technical note that the existence of a soil-porous stones interaction prevents the elimination of porous stones' influence, leading to unreliable permeability results. A practical solution based on manufacturing unique porous stones (MS) is suggested in an attempt to eliminate such an influence. The porous stones influence is highlighted by running excess pore pressure dissipation tests in Triaxial conditions with calibrated beads. The results show a soil-porous stones interaction and a flowrate increase up ...

Research paper thumbnail of Effect of the temperature on the water transport by capillarity into the concrete porosity

Research paper thumbnail of Data base for liquefaction studies - Triaxial simple shear test results (TxSS) Ottawa sand (C-109)

Research paper thumbnail of Pore-scale study of permeability and tortuosity for flow through particulate media using virtual approach

In this paper, Lattice Boltzmann method (LBM) has been used to study the effects of permeability ... more In this paper, Lattice Boltzmann method (LBM) has been used to study the effects of permeability and tortuosity on flow through saturated particulate media and identify the relationships between permeability and tortuosity with other parameters such as particles diameter, grain specific surface, and porosity. LBM is a simple kinematic model that can incorporate the essential physics of microscopic and mesoscopic processes involved in flow through granular soils. The obtained results indicate that the 2D LB model, due to its inherent theoretical advantages, is capable of demonstrating that the porosity and specific surface are the most influential parameters in determining the intrinsic permeability of granular media. The obtained results show that particles' size diameter has a twofold effect on the coefficient of permeability: one is through specific surface and the other is by tortuosity factor. Numerical study also reveals that tortuosity of granular soils decreases almost linearly with increasing the porosity.

Research paper thumbnail of Parallel algorithm for fractal model of creation of soil structure using particles-size distributions

Journal of physics, Oct 15, 2012

View the article online for updates and enhancements. You may also like Simulation of wave impact... more View the article online for updates and enhancements. You may also like Simulation of wave impact on shore protection structures using 3D model of wave processes S V Protsenko-The condition assessment scheme for ancient timber structure using material and deformation analysis W Juan and A D Putri-A Comparative Analysis on the Methods of Strengthening Isolated Reinforced Concrete Columns Mungur Ved Vritesh and Seeboo Asish

Research paper thumbnail of Toward the prediction of rheological properties of self-consolidating concrete as diphasic material

Construction and Building Materials, 2019

The relationship between SCC and its corresponding suspending phase was evaluated. The rheologica... more The relationship between SCC and its corresponding suspending phase was evaluated. The rheological properties of sieved and modified mortars are well correlated. The VP/VS, W/B, and suspending phase affect the intrinsic viscosity. The proposed modified models were extended to predict rheological properties.

Research paper thumbnail of Finite volume analysis of reinforced concrete structure cracking using a thermo-plastic-damage model

This paper proposes modifications to the phenomenological model formulation called CDPM2 develope... more This paper proposes modifications to the phenomenological model formulation called CDPM2 developed by Grassl et al. (2013). The proposed modifications are designed to enhance model performance with coupling to temperature effects. A very strong coupling between nonlinear elasticity, plasticity, nonlocal damage evolution and temperature gradient is used to simulate arbitrary crack propagation. The use of FVM to model solid damage is a numerical challenge. This approach presents some advantages such as: ensuring that discretization is conservative even when the geometry is changing; providing a simple formulation that can be obtained directly from a difference method; and employing unstructured meshes. Most authors have neglected the nonlinearity of concrete in the elastic domain from the start of loading to the plastic domain. In this paper we confirm that concrete rheology is not linear even under low loading. Also, since the so-called fracture energy is a key parameter needed to determine crack size and how they propagate in space, we consider that the fracture energy is both material and geometrical parameter dependent. For this reason, we developed a new approach which includes adaptive mesh, nonlinear rheology and thermal effects to recalculate fracture energy at each time step. Many authors use a constant value obtained from experiments to calculate fracture energy, others use a numerical correlation. In this study, the fracture energy parameter is not constant and can vary with temperature or/and with a change in geometry due to concrete failure. As is well known, mesh quality of complex geometries is very important for determining accurate predictions. A new meshing tool was developed using the C ++ programming language. This tool is faster, more accurate and produces a high quality structured mesh. The predictions obtained were compared to a wide variety of experimental data and showed good agreement.

Research paper thumbnail of Small strain stiffness and stiffness degradation curve of sensitive Champlain clay

Research paper thumbnail of Validation of strain/energy-based pore pressure model in one-dimensional response analyses using centrifuge tests

Soil Dynamics and Earthquake Engineering

Research paper thumbnail of 2-D Pore-Particle Scale Model of the Erosion at the Boundary of Two Soils under Horizontal Groundwater Flow

Scour and Erosion, 2010

Modeling particle-fluid systems in porous media encountered in many scientific and engineering ap... more Modeling particle-fluid systems in porous media encountered in many scientific and engineering applications presents a significant challenge. This paper outlines a hydrodynamic flow at a low Reynolds number through saturated porous media which is generated virtually using only the grain-size distribution curves of soils. In order to represent the pore and granular structures of soils, a novel model was developed using a fractal approach. For a given porosity, particle and pore size distributions were successfully modeled for a wide range of soils. We tested the model ' s conductivity behaviour by carrying out a steady-state flow through a fractal structure. Soil particle movement was modeled using the discrete element method (DEM), and the hydrodynamic flow was simulated by the well-known marker-andcells (MAC) method, with special conditions imposed at the particle boundaries. The fluid-particle interaction was taken into account in our calculations using the method of direct force integration at the surface of particles. Several comparisons of our numerical results to those of published experiments for particle-particle and particlewall interaction in a viscous fluid show very good agreement. Finally, an example of a possible erosion scenario at the interface of two different soils under a horizontal flow is presented. The results and a discussion of this model ' s applicability are also presented. This study is a part of an extensive program which includes 3-D simulations aimed at gaining a better understanding erosion phenomena in soils made up of irregularly shaped particles under hydrodynamic flow.

Research paper thumbnail of Inspection of the lids of shallowly buried concrete structures based on the propagation of surface waves- PART II

Journal of Applied Geophysics, 2018

The inspection of underground concrete utility structures can be a challenging task due to their ... more The inspection of underground concrete utility structures can be a challenging task due to their inaccessibility. This article presents a nondestructive inspection technique for the lids of such structures based on the propagation of elastic waves where the variation in soil vertical acceleration following an impact is recorded along a given line at the surface of the soil. The structures investigated are made of reinforced concrete and are located below a shallow homogeneous soil layer which is covered by a pavement. It is shown through finite difference numerical modeling that elastic waves are affected by the state of degradation of the underground concrete structure. It is also shown that the difference in dynamic properties between the soil and the concrete structure causes the latter to act as a waveguide that affects the variation of the vertical acceleration measured at the surface of the model. The propagation of elastic waves within different underground profiles is studied in terms of the variation of their energy and of their group and phase velocity. Theoretical models, computed using the propagator matrix technique, are presented in the appendix to demonstrate the importance of the waveguide effects, caused by the presence of the concrete structure, on the group and phase velocity dispersion curves of Rayleigh waves. Finally, some of the results obtained from the inspection of two different real underground structures are also presented. These results show that the proposed inspection technique, developed based on 1D and 2D numerical testing, is also effective for real structures.

Research paper thumbnail of Virtual Approach to Simulating Geotechnical Problems under Both Static and Dynamic Conditions

World Academy of Science, Engineering and Technology, International Journal of Geotechnical and Geological Engineering, 2017

Research paper thumbnail of 3D Virtual Laborato Ry for Geotechnical Applications: Another Perspective

Research paper thumbnail of Numerical Modeling of Water Transport in Ultra-High-Performance Fiber-Reinforced Concrete

Rilem bookseries, Jul 1, 2022

Research paper thumbnail of Laboratory Measurement of Permeability in Postseismic Flow

International Journal of Geomechanics

Research paper thumbnail of Virtual reality 3d simulation of fluide-particle interaction

COUPLED V : proceedings of the V International Conference on Computational Methods for Coupled Problems in Science and Engineering :, 2013

Research paper thumbnail of A More Comprehensive Modeling of Contact Force During Shear Testing Using Dem

Proceedings of the VII European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS Congress 2016), 2016

Research paper thumbnail of Strain rate effect on static and dynamic behaviors of eastern Canada fine-grained soils

Canadian Geotechnical Journal, 2021

The assessment of the strain rate effect on the geotechnical properties of soils constitutes an i... more The assessment of the strain rate effect on the geotechnical properties of soils constitutes an important step toward a more accurate analysis of their response. This study presents the experimental results of monotonic and cyclic simple shear tests performed to examine the strain rate ([Formula: see text]) effect on the behavior of eastern Canada soils. Nine natural soils sampled from different locations in eastern Canada were used in this study. The tests were performed on a simple shear device using a strain-controlled mode. In addition to the obtained experimental results, published data in the literature were used to draw the conclusions of this study. Analysis of the data indicates that the undrained shear strength (τf) increases proportionally with the strain rate by approximately 6%–17% per log cycle of [Formula: see text]. The results also show that the secant shear modulus G increases with the strain rate, especially at large strain amplitudes. Moreover, the analysis of th...

Research paper thumbnail of Experimental and numerical investigation of the Saint-Adelphe landslide after the 1988 Saguenay earthquake

Canadian Geotechnical Journal, 2020

On 25 November 1988, after the Saguenay earthquake, a landslide occurred in the municipality of S... more On 25 November 1988, after the Saguenay earthquake, a landslide occurred in the municipality of Saint-Adelphe. The soil profile indicated that the deposit was composed of a stiff clay crustal layer overlying sensitive plastic clay with a soft-to-stiff consistency. A geotechnical investigation was carried out in situ and in the laboratory and included the use of a new seismic simulator to develop a geotechnical model of the Saint-Adelphe clay. The model was incorporated in a finite-difference slope stability analysis before and during the earthquake. The results showed the development of plastic zones and the generation of pore water pressure, but the global safety factor remained above unity. A post-seismic analysis that utilized a strain-softening behavior model showed the initiation and propagation of the plastic zone, as well as the development of a failure surface close to the observed failure surface. Therefore, it is proposed that the Saint-Adelphe landslide could be explained...

Research paper thumbnail of New Model of Shear Modulus Degradation and Damping Ratio curves for Sensitive Canadian Clays

Canadian Geotechnical Journal

This study investigated a new predictive model of the shear modulus reduction () and damping rati... more This study investigated a new predictive model of the shear modulus reduction () and damping ratio () curves for sensitive eastern Canada clays. The model was established based on experimental measurements of and performed on 69 sensitive clay specimens from eastern Canada. The compiled database was first analyzed to qualitatively assess the influences of different soil parameters on the measurements. Next, statistical analyses using regression analysis and the modified hyperbolic model were performed. It was found that the and values of sensitive eastern Canada clays were influenced mainly by the plasticity index (Ip), mean effective stress , and structure, which was quantified by the liquidity index (IL). Based on the statistical analysis performed, new equations for and were proposed. The newly proposed model was compared with previously published models. The comparison clearly showed that the proposed model was more representative of sensitive eastern Canada clays. Consequently,...

Research paper thumbnail of Porous Stones in Permeability Measurement: Drawbacks and Solution

Canadian Geotechnical Journal

Porous stones are commonly used in geotechnical laboratory testing to provide solid support at th... more Porous stones are commonly used in geotechnical laboratory testing to provide solid support at the two ends of the tested specimen. Although porous stones can have several advantages, they can induce a hydraulic impedance that might alter the flowrate results. Numerous suggestions and recommendations were issued to avoid some of the problems encountered when using porous stones, such as clogging and stones' low permeability coefficient (Kp). However, it is proven in this technical note that the existence of a soil-porous stones interaction prevents the elimination of porous stones' influence, leading to unreliable permeability results. A practical solution based on manufacturing unique porous stones (MS) is suggested in an attempt to eliminate such an influence. The porous stones influence is highlighted by running excess pore pressure dissipation tests in Triaxial conditions with calibrated beads. The results show a soil-porous stones interaction and a flowrate increase up ...

Research paper thumbnail of Effect of the temperature on the water transport by capillarity into the concrete porosity

Research paper thumbnail of Data base for liquefaction studies - Triaxial simple shear test results (TxSS) Ottawa sand (C-109)