The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Jacques Ohayon - One of the best experts on this subject based on the ideXlab platform.
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an original force Displacement Relationship for spherical inclusions in multilayered viscoelastic finite media
Mechanics of Materials, 2010Co-Authors: Nicolas Mesnier, Philippe Tracqui, Jacques OhayonAbstract:Abstract This paper presents original solutions of the force–Displacement Relationships for a rigid spherical bead embedded in a composite medium made of n-isotropic linearly viscoelastic finite layers. Analytical solutions were provided for both compressible and incompressible elastic and viscoelastic solids, assuming no-slip conditions between the rigid spherical inclusion and its adjacent medium as well as between each layer of the composite medium. Thanks to these general formulas, we investigated the effect of finite size media on the force-bead Displacement response and derived the exact Relationship linking apparent and intrinsic elastic moduli of the medium. Such theoretical solutions can be interestingly applied to identify layer’s heterogeneities and to characterize accurately the mechanical properties of living material like cells when using translational microrheology assays. This point is especially illustrated by modeling animal cell cytoskeleton as a bilayer composite medium probed by magnetic tweezers. Interestingly, our results highlighted the influence of finite cell size effects, while allowing to distinguish viscoelastic properties of deep cell cytoskeleton from those of cellular cortex. Moreover, we established that translational microrheology experiments are well suited to characterize locally the viscoelasticity properties of the layer in contact with the probe as soon this layer thickness is larger than ten bead diameters.
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An original force–Displacement Relationship for spherical inclusions in multilayered viscoelastic finite media
Mechanics of Materials, 2010Co-Authors: Nicolas Mesnier, Philippe Tracqui, Jacques OhayonAbstract:This paper presents original solutions of the force–Displacement Relationships for a rigid spherical bead embedded in a composite medium made of n-isotropic linearly viscoelastic finite layers. Analytical solutions were provided for both compressible and incompressible elastic and viscoelastic solids, assuming no-slip conditions between the rigid spherical inclusion and its adjacent medium as well as between each layer of the composite medium. Thanks to these general formulas, we investigated the effect of finite size media on the force-bead Displacement response and derived the exact Relationship linking apparent and intrinsic elastic moduli of the medium. Such theoretical solutions can be interestingly applied to identify layer’s heterogeneities and to characterize accurately the mechanical properties of living material like cells when using translational microrheology assays. This point is especially illustrated by modeling animal cell cytoskeleton as a bilayer composite medium probed by magnetic tweezers. Interestingly, our results highlighted the influence of finite cell size effects, while allowing to distinguish viscoelastic properties of deep cell cytoskeleton from those of cellular cortex. Moreover, we established that translational microrheology experiments are well suited to characterize locally the viscoelasticity properties of the layer in contact with the probe as soon this layer thickness is larger than ten bead diameters.
Ss Xu - One of the best experts on this subject based on the ideXlab platform.
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effect of sampling and linkage on fault length and length Displacement Relationship
International Journal of Earth Sciences, 2006Co-Authors: Ss Xu, Angel F Nietosamaniego, Susana A Alanizalvarez, L G VelasquillomartinezAbstract:The power-law exponent (n) in the equation: D=cL n , with D = maximum Displacement and L = fault length, would be affected by deviations of fault trace length. (1) Assuming n=1, numerical simulations on the effect of sampling and linkage on fault length and length–Displacement Relationship are done in this paper. The results show that: (a) uniform relative deviations, which means all faults within a dataset have the same relative deviation, do not affect the value of n; (b) deviations of the fault length due to unresolved fault tip decrease the values of n and the deviations of n increase with the increasing length deviations; (c) fault linkage and observed dimensions either increase or decrease the value of n depending on the distribution of deviations within a dataset; (d) mixed deviations of the fault lengths are either negative or positive and cause the values of n to either decrease or increase; (e) a dataset combined from two or more datasets with different values of c and orders of magnitude also cause the values of n to deviate. (2) Data including 19 datasets and spanning more than eight orders of fault length magnitudes (10−2–105 m) collected from the published literature indicate that the values of n range from 0.55 to 1.5, the average value being 1.0813, and the peak value of n d (double regression) is 1.0–1.1. Based on above results from the simulations and published data, we propose that the Relationship between the maximum Displacement and fault length in a single tectonic environment with uniform mechanical properties is linear, and the value of n deviated from 1 is mainly caused by the sampling and linkage effects.
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Effect of sampling and linkage on fault length and length–Displacement Relationship
International Journal of Earth Sciences, 2006Co-Authors: Ss Xu, Ángel F. Nieto-samaniego, Susana A. Alaniz-Álvarez, L. G. Velasquillo-martínezAbstract:The power-law exponent (n) in the equation: D=cL n , with D = maximum Displacement and L = fault length, would be affected by deviations of fault trace length. (1) Assuming n=1, numerical simulations on the effect of sampling and linkage on fault length and length–Displacement Relationship are done in this paper. The results show that: (a) uniform relative deviations, which means all faults within a dataset have the same relative deviation, do not affect the value of n; (b) deviations of the fault length due to unresolved fault tip decrease the values of n and the deviations of n increase with the increasing length deviations; (c) fault linkage and observed dimensions either increase or decrease the value of n depending on the distribution of deviations within a dataset; (d) mixed deviations of the fault lengths are either negative or positive and cause the values of n to either decrease or increase; (e) a dataset combined from two or more datasets with different values of c and orders of magnitude also cause the values of n to deviate. (2) Data including 19 datasets and spanning more than eight orders of fault length magnitudes (10−2–105 m) collected from the published literature indicate that the values of n range from 0.55 to 1.5, the average value being 1.0813, and the peak value of n d (double regression) is 1.0–1.1. Based on above results from the simulations and published data, we propose that the Relationship between the maximum Displacement and fault length in a single tectonic environment with uniform mechanical properties is linear, and the value of n deviated from 1 is mainly caused by the sampling and linkage effects.
L G Velasquillomartinez - One of the best experts on this subject based on the ideXlab platform.
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effect of sampling and linkage on fault length and length Displacement Relationship
International Journal of Earth Sciences, 2006Co-Authors: Ss Xu, Angel F Nietosamaniego, Susana A Alanizalvarez, L G VelasquillomartinezAbstract:The power-law exponent (n) in the equation: D=cL n , with D = maximum Displacement and L = fault length, would be affected by deviations of fault trace length. (1) Assuming n=1, numerical simulations on the effect of sampling and linkage on fault length and length–Displacement Relationship are done in this paper. The results show that: (a) uniform relative deviations, which means all faults within a dataset have the same relative deviation, do not affect the value of n; (b) deviations of the fault length due to unresolved fault tip decrease the values of n and the deviations of n increase with the increasing length deviations; (c) fault linkage and observed dimensions either increase or decrease the value of n depending on the distribution of deviations within a dataset; (d) mixed deviations of the fault lengths are either negative or positive and cause the values of n to either decrease or increase; (e) a dataset combined from two or more datasets with different values of c and orders of magnitude also cause the values of n to deviate. (2) Data including 19 datasets and spanning more than eight orders of fault length magnitudes (10−2–105 m) collected from the published literature indicate that the values of n range from 0.55 to 1.5, the average value being 1.0813, and the peak value of n d (double regression) is 1.0–1.1. Based on above results from the simulations and published data, we propose that the Relationship between the maximum Displacement and fault length in a single tectonic environment with uniform mechanical properties is linear, and the value of n deviated from 1 is mainly caused by the sampling and linkage effects.
Jinchun Chai - One of the best experts on this subject based on the ideXlab platform.
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prediction of pullout resistance and pullout force Displacement Relationship for inextensible grid reinforcements
Soils and Foundations, 1996Co-Authors: D T Bergado, Jinchun Chai, Norihiko MiuraAbstract:A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout Displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout Displacement Relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout Displacement Relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/D, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.
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Pullout force/Displacement Relationship of extensible grid reinforcements
Geotextiles and Geomembranes, 1994Co-Authors: D T Bergado, Jinchun ChaiAbstract:Abstract A model for predicting the pullout resistance of polymer-grid reinforcement has been proposed. The influence of bearing member rigidity and spacing ratio (S/D) are explicitly expressed in the hyperbolic model. A new bearing capacity equation is incorporated for calculating the maximum pullout force. The Displacement along the reinforcement is calculated by using the proposed pullout bearing resistance model together with the elongation of the grid longitudinal member. The validity of the method is confirmed by good agreement between calculated values and actual test data. The analytically determined effective reinforcement embedment lengths (i.e. the length of the reinforcement in tension) and pullout Displacement to mobilize the desired pullout resistance of polymeric grids under different backfill conditions and under different applied normal pressures, provide useful information for the design of reinforced earth structures against pullout failure.
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pullout force Displacement Relationship of extensible grid reinforcements
Geotextiles and Geomembranes, 1994Co-Authors: D T Bergado, Jinchun ChaiAbstract:Abstract A model for predicting the pullout resistance of polymer-grid reinforcement has been proposed. The influence of bearing member rigidity and spacing ratio (S/D) are explicitly expressed in the hyperbolic model. A new bearing capacity equation is incorporated for calculating the maximum pullout force. The Displacement along the reinforcement is calculated by using the proposed pullout bearing resistance model together with the elongation of the grid longitudinal member. The validity of the method is confirmed by good agreement between calculated values and actual test data. The analytically determined effective reinforcement embedment lengths (i.e. the length of the reinforcement in tension) and pullout Displacement to mobilize the desired pullout resistance of polymeric grids under different backfill conditions and under different applied normal pressures, provide useful information for the design of reinforced earth structures against pullout failure.
Nicolas Mesnier - One of the best experts on this subject based on the ideXlab platform.
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an original force Displacement Relationship for spherical inclusions in multilayered viscoelastic finite media
Mechanics of Materials, 2010Co-Authors: Nicolas Mesnier, Philippe Tracqui, Jacques OhayonAbstract:Abstract This paper presents original solutions of the force–Displacement Relationships for a rigid spherical bead embedded in a composite medium made of n-isotropic linearly viscoelastic finite layers. Analytical solutions were provided for both compressible and incompressible elastic and viscoelastic solids, assuming no-slip conditions between the rigid spherical inclusion and its adjacent medium as well as between each layer of the composite medium. Thanks to these general formulas, we investigated the effect of finite size media on the force-bead Displacement response and derived the exact Relationship linking apparent and intrinsic elastic moduli of the medium. Such theoretical solutions can be interestingly applied to identify layer’s heterogeneities and to characterize accurately the mechanical properties of living material like cells when using translational microrheology assays. This point is especially illustrated by modeling animal cell cytoskeleton as a bilayer composite medium probed by magnetic tweezers. Interestingly, our results highlighted the influence of finite cell size effects, while allowing to distinguish viscoelastic properties of deep cell cytoskeleton from those of cellular cortex. Moreover, we established that translational microrheology experiments are well suited to characterize locally the viscoelasticity properties of the layer in contact with the probe as soon this layer thickness is larger than ten bead diameters.
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An original force–Displacement Relationship for spherical inclusions in multilayered viscoelastic finite media
Mechanics of Materials, 2010Co-Authors: Nicolas Mesnier, Philippe Tracqui, Jacques OhayonAbstract:This paper presents original solutions of the force–Displacement Relationships for a rigid spherical bead embedded in a composite medium made of n-isotropic linearly viscoelastic finite layers. Analytical solutions were provided for both compressible and incompressible elastic and viscoelastic solids, assuming no-slip conditions between the rigid spherical inclusion and its adjacent medium as well as between each layer of the composite medium. Thanks to these general formulas, we investigated the effect of finite size media on the force-bead Displacement response and derived the exact Relationship linking apparent and intrinsic elastic moduli of the medium. Such theoretical solutions can be interestingly applied to identify layer’s heterogeneities and to characterize accurately the mechanical properties of living material like cells when using translational microrheology assays. This point is especially illustrated by modeling animal cell cytoskeleton as a bilayer composite medium probed by magnetic tweezers. Interestingly, our results highlighted the influence of finite cell size effects, while allowing to distinguish viscoelastic properties of deep cell cytoskeleton from those of cellular cortex. Moreover, we established that translational microrheology experiments are well suited to characterize locally the viscoelasticity properties of the layer in contact with the probe as soon this layer thickness is larger than ten bead diameters.