Figure 1.
Particle size distribution of jumunjin sand.
Figure 1.
Particle size distribution of jumunjin sand.
Figure 2.
Shear rate dependent viscosity reduction of xanthan gum hydrogels at different xanthan gum to water (Mxg/Mw) ratios in mass.
Figure 2.
Shear rate dependent viscosity reduction of xanthan gum hydrogels at different xanthan gum to water (Mxg/Mw) ratios in mass.
Figure 3.
Structural materials: (a) schematic diagram; (b) typical surface profiles.
Figure 3.
Structural materials: (a) schematic diagram; (b) typical surface profiles.
Figure 4.
Schematic diagram of experimental setup: (a) direct shear test; (b) interface shear test.
Figure 4.
Schematic diagram of experimental setup: (a) direct shear test; (b) interface shear test.
Figure 5.
Direct shear test results of xanthan gum-treated soil: (a,c,e) direct shear stress (τ)-horizontal shear displacement (δ) curves; (b,d,f) vertical strain (εv)-horizontal shear displacement (δ) curves.
Figure 5.
Direct shear test results of xanthan gum-treated soil: (a,c,e) direct shear stress (τ)-horizontal shear displacement (δ) curves; (b,d,f) vertical strain (εv)-horizontal shear displacement (δ) curves.
Figure 6.
Peak and residual strength of xanthan gum-treated sand: (a,b) initial condition; (c,d) dry condition; (e,f) resubmerged condition.
Figure 6.
Peak and residual strength of xanthan gum-treated sand: (a,b) initial condition; (c,d) dry condition; (e,f) resubmerged condition.
Figure 7.
Interfacial shear test results of xanthan gum-treated soil without asperities (Interface I): (a,c,e,g) interface shear stress (τ)-horizontal shear displacement (δ) curves; (b,d,f,h) vertical strain (εv)-horizontal shear displacement (δ) curves.
Figure 7.
Interfacial shear test results of xanthan gum-treated soil without asperities (Interface I): (a,c,e,g) interface shear stress (τ)-horizontal shear displacement (δ) curves; (b,d,f,h) vertical strain (εv)-horizontal shear displacement (δ) curves.
Figure 8.
Peak and residual strengths of xanthan gum-treated sand shearing at interface without asperities (Interface I): (a,b) initial condition; (c,d) dry condition; (e,f) resubmerged condition.
Figure 8.
Peak and residual strengths of xanthan gum-treated sand shearing at interface without asperities (Interface I): (a,b) initial condition; (c,d) dry condition; (e,f) resubmerged condition.
Figure 9.
Interfacial shear test results of xanthan gum-treated soil shearing including asperity (interfaces II, III, IV): (a,c,e) interface shear stress (τ)-horizontal shear displacement (δ) curves; (b,d,f) vertical strain (εv)-horizontal shear displacement (δ) curves.
Figure 9.
Interfacial shear test results of xanthan gum-treated soil shearing including asperity (interfaces II, III, IV): (a,c,e) interface shear stress (τ)-horizontal shear displacement (δ) curves; (b,d,f) vertical strain (εv)-horizontal shear displacement (δ) curves.
Figure 10.
Peak strengths of xanthan gum-treated sand obtained from direct and interfacial shear tests.
Figure 10.
Peak strengths of xanthan gum-treated sand obtained from direct and interfacial shear tests.
Figure 11.
Residual strengths of xanthan gum-treated sand obtained from direct and interfacial shear tests.
Figure 11.
Residual strengths of xanthan gum-treated sand obtained from direct and interfacial shear tests.
Figure 12.
Internal shear parameters of xanthan gum-treated sand (soil–soil shearing): (a) peak internal friction angle (ϕpeak), (b) peak cohesion (cpeak), (c) residual internal friction angle (ϕresidual), and (d) residual cohesion (cresidual).
Figure 12.
Internal shear parameters of xanthan gum-treated sand (soil–soil shearing): (a) peak internal friction angle (ϕpeak), (b) peak cohesion (cpeak), (c) residual internal friction angle (ϕresidual), and (d) residual cohesion (cresidual).
Figure 13.
Peak interfacial shear parameters of xanthan gum-treated sand (soil–structure interface): (a,b) peak interface friction angle (δpeak) and adhesion (capeak) in initial state, (c,d) peak interface friction angle (δpeak) and adhesion (capeak) in dried state, and (e,f) peak interface friction angle (δpeak) and adhesion (capeak) in resubmerged state.
Figure 13.
Peak interfacial shear parameters of xanthan gum-treated sand (soil–structure interface): (a,b) peak interface friction angle (δpeak) and adhesion (capeak) in initial state, (c,d) peak interface friction angle (δpeak) and adhesion (capeak) in dried state, and (e,f) peak interface friction angle (δpeak) and adhesion (capeak) in resubmerged state.
Figure 14.
Residual interfacial shear parameters of xanthan gum-treated sand (soil–structure interface): (a,b) residual interface friction angle (δresidual) and adhesion (caresidual) in initial state, (c,d) residual interface friction angle (δresidual) and adhesion (caresidual) in dried state, and (e,f) residual interface friction angle (δresidual) and adhesion (caresidual) in resubmerged state.
Figure 14.
Residual interfacial shear parameters of xanthan gum-treated sand (soil–structure interface): (a,b) residual interface friction angle (δresidual) and adhesion (caresidual) in initial state, (c,d) residual interface friction angle (δresidual) and adhesion (caresidual) in dried state, and (e,f) residual interface friction angle (δresidual) and adhesion (caresidual) in resubmerged state.
Figure 15.
Relationship between internal and interface friction angle of xanthan gum-treated sand.
Figure 15.
Relationship between internal and interface friction angle of xanthan gum-treated sand.
Table 1.
Properties of sand used in this study.
Table 1.
Properties of sand used in this study.
Mean Grain Size D50 [mm] | Specific Gravity Gs [-] | Coefficient of Uniformity Cu [-] | Coefficient of Curvature Cc [-] | Maximum Void Ratio emax [-] | Minimum Void Ratio emin [-] | USCS |
---|
0.47 | 2.65 | 1.12 | 0.98 | 0.95 | 0.644 | SP |
Table 2.
Normalized relative roughness (Rn) used in this study.
Table 2.
Normalized relative roughness (Rn) used in this study.
Interface Condition (Type) | Rn in mm (D50) | References |
---|
Rn in this study | 0.12 (D50 = 0.47) | |
Very rough steel | 0.43 (D50 = 0.65) | [31] |
Rough steel | 0.17 (D50 = 0.65) |
Intermediate steel | 0.08 (D50 = 0.65) |
Smooth steel | 0.03 (D50 = 0.65) |
Brass | 0.03 (D50 = 0.65) | [32] |
#120 Sand paper | 0.26 (D50 = 0.65) |
#50 Sand paper | 1.14 (D50 = 0.65) |
Smooth concrete | 0.002 (D50 = 0.5) | [33] |
Medium concrete | 0.12 (D50 = 0.5) |
Rough concrete | 0.2 (D50 = 0.5) |
Smooth woven geotextile | 0.03 (D50 = 0.65) | [34] |
Moderately rough woven geotextile | 0.19 (D50 = 0.65) |
Rougher woven geotextile | 0.30 (D50 = 0.65) |
Table 3.
Experimental conditions.
Table 3.
Experimental conditions.
Variables | Direct Shear Test | Interface Shear Test |
---|
Shearing condition | Soil–soil | Soil–solid structure |
Moisture state | Initial state Dried state Resubmerged state | Initial state Dried state Resubmerged state |
Xanthan gum concentration [MXG/MS,%] | 0, 0.5, 1, 2 | 0, 0.5, 1, 2 |
Vertical confinement pressure [kPa] | 50, 100, 200, 400 | 50, 100, 200, 400 |
Table 4.
Mohr–Coulomb failure parameters determined from linear regression (soil–soil shearing).
Table 4.
Mohr–Coulomb failure parameters determined from linear regression (soil–soil shearing).
Hydrogel State | Xanthan Gum MXG/MS [%] | Peak Strength | Residual Strength |
---|
Cohesion [kPa] | Friction Angle [°] | Cohesion [kPa] | Friction Angle [°] |
---|
Initial | 0.0 | <1 | 39.0 | <1 | 33.6 |
0.5 | 2.5 | 38.1 | <1 | 31.1 |
1.0 | 8.5 | 36.9 | <1 | 29.6 |
2.0 | 23.2 | 34.6 | <1 | 31.7 |
Dried (Initial → Dried) | 0.0 | <1 | 39.0 | <1 | 33.6 |
0.5 | 117.1 | 45.4 | 28.2 | 36.8 |
1.0 | 307.7 | 51.6 | 34.9 | 39.5 |
2.0 | 563.7 | 53.7 | 45.1 | 46.3 |
Resubmerged (Initial → Dried → Resubmerged) | 0.0 | <1 | 39.0 | <1 | 33.6 |
0.5 | 11.4 | 38.6 | 3.6 | 30.7 |
1.0 | 23.3 | 37.9 | 12.8 | 30.3 |
2.0 | 41.1 | 35.3 | 21.7 | 29.4 |
Table 5.
Mohr–Coulomb failure parameters determined from linear regression (Interface I).
Table 5.
Mohr–Coulomb failure parameters determined from linear regression (Interface I).
Hydrogel State | MXG/MS [%] | Peak Strength | Residual Strength |
---|
Adhesion [kPa] | Interface Friction Angle [°] | Adhesion [kPa] | Interface Friction Angle [°] |
---|
Initial | 0.0 | 3.1 | 28.6 | 4.1 | 27.1 |
0.5 | <1 | 26.610 | <1 | 26.1 |
1.0 | 2.2 | 26.3 | 2.2 | 26.3 |
2.0 | <1 | 26.7 | 1.2 | 26.6 |
Dried (1) | 0.0 | 3.2 | 28.6 | <1 | 28.3 |
0.5 | 7.1 | 30.1 | <1 | 28.7 |
1.0 | 15.1 | 30.7 | 3.1 | 29.6 |
2.0 | 21.5 | 35.1 | <1 | 32.8 |
Resubmerged (2) | 0.0 | 3.1 | 28.6 | 4.1 | 27.1 |
0.5 | <1 | 28.3 | <1 | 26.6 |
1.0 | 2.8 | 26.9 | 2.3 | 27.0 |
2.0 | 2.0 | 27.6 | <1 | 27.5 |
Table 6.
Mohr–Coulomb failure parameters determined from linear regression (interface II, III, and IV).
Table 6.
Mohr–Coulomb failure parameters determined from linear regression (interface II, III, and IV).
Interface | Hydrogel State | MXG/MS [%] | Peak Strength | Residual Strength |
---|
Adhesion [kPa] | Interface Friction Angle [°] | Adhesion [kPa] | Interface Friction Angle [°] |
---|
Interface II | Initial | 0.0 | 3.8 | 34.3 | 0.2 | 32.2 |
0.5 | <1 | 33.4 | <1 | 30.5 |
1.0 | <1 | 31.9 | 4.0 | 28.7 |
2.0 | 3.0 | 31.9 | 1.7 | 28.5 |
Dried | 0.0 | 2.6 | 34.3 | <1 | 29.7 |
0.5 | 10.5 | 35.4 | <1 | 35.7 |
1.0 | 17.6 | 38.0 | 7.4 | 35.3 |
2.0 | 28.7 | 45.9 | 7.1 | 39.4 |
Resubmerged | 0.0 | 3.8 | 34.3 | <1 | 32.2 |
0.5 | <1 | 35.4 | 1.3 | 30.9 |
1.0 | <1 | 35.7 | <1 | 31.5 |
2.0 | 6.0 | 31.1 | 2.8 | 31.2 |
Interface III | Initial | 0.0 | 6.5 | 35.5 | 1.6 | 32.4 |
0.5 | 2.3 | 33.6 | <1 | 30.7 |
1.0 | 2.8 | 31.7 | 4.1 | 29.0 |
2.0 | 2.0 | 32.4 | 0.5 | 30.6 |
Dried | 0.0 | 1.8 | 35.5 | 4.2 | 29.7 |
0.5 | 26.6 | 38.2 | 7.9 | 36.1 |
1.0 | 52.2 | 40.4 | 15.1 | 37.0 |
2.0 | 59.0 | 50.2 | 23.8 | 39.2 |
Resubmerged | 0.0 | 6.5 | 35.5 | 1.6 | 32.4 |
0.5 | 6.6 | 34.6 | <1 | 32.5 |
1.0 | 7.2 | 34.5 | <1 | 31.2 |
2.0 | 6.9 | 36.8 | <1 | 32.6 |
Interface IV | Initial | 0.0 | 2.3 | 36.7 | <1 | 32.8 |
0.5 | 4.0 | 32.6 | <1 | 31.4 |
1.0 | 1.5 | 32.0 | 4.6 | 28.8 |
2.0 | 2.5 | 32.8 | 2.6 | 30.9 |
Dried | 0.0 | 2.0 | 36.7 | 6.6 | 29.8 |
0.5 | 53.2 | 38.5 | 15.1 | 35.4 |
1.0 | 68.6 | 43.2 | 22.3 | 36.2 |
2.0 | 80.0 | 53.3 | 25.2 | 39.6 |
Resubmerged | 0.0 | 2.3 | 36.7 | <1 | 32.8 |
0.5 | 5.3 | 35.4 | <1 | 31.8 |
1.0 | 4.5 | 36.6 | 2.0 | 31.2 |
2.0 | 10.1 | 35.9 | 4.7 | 31.5 |