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. 2023 Oct 27;9(11):850.
doi: 10.3390/gels9110850.

Strength Assessment of Water-Glass Sand Mixtures

Toshiyuki Motohashi  1 , Shigeo Sasahara  2 , Shinya Inazumi  3
Affiliations

Strength Assessment of Water-Glass Sand Mixtures

Toshiyuki Motohashi et al. Gels. .

Abstract

For years, the chemical injection process has aided construction works by increasing the strength and water-sealing efficiency of sandy soil. Despite its growing popularity in projects, such as seismic strengthening and liquefaction mitigation, a unified understanding of how chemically treated soil develops its strength, especially under static conditions, remains elusive. Some studies have proposed that strength is derived from the tensile effects of dilatancy, where shearing of the sandy soil causes expansion, creating tension in the interstitial hydrogel and resulting in negative pressure that consolidates the soil particles. Other studies, however, attribute this strength development to the volumetric shrinkage of the hydrogel, which the authors argue confines and compresses the sandy soil particles. Challenges are encountered with this theory, particularly with respect to the consistency of the volumetric shrinkage measurements and the timing of these measurements in relation to changes in soil strength. The aim of the current research is to shed light on this mechanism by using consolidation drainage triaxial compression (CD) tests to measure the cohesive strength and internal friction angle of chemically enhanced soil. By eliminating the dilatancy-induced negative pressure effects and coupling this with an analysis of the molecular structure of the hydrogel, the present study provides an in-depth look at the strength development mechanism and its durability. This holistic approach not only fills in the existing gaps in the understanding of this mechanism, but also paves the way for optimized construction techniques.

Keywords: chemical injection; consolidation drainage triaxial compression test; hydrogel; sand-gel; small angle X-ray scattering test.

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Conflict of interest statement

The authors declare no conflict of interest. In this paper, Osaka Bousui Construction Co. Ltd., of which the first author is a member, mainly conducted the physical and mechanical investigations, and Fuji Chemical Co. Ltd., of which the second author is a member, mainly conducted the chemical investigations. The last author, Shibaura Institute of Technology, summarized these studies. The paper reflects the views of the scientists and not the company.

Figures

Figure 1
Figure 1
Particle size distribution curve of Tohoku silica sand No. 5.
Figure 2
Figure 2
Appearance of beamline BL8S3.
Figure 3
Figure 3
Schematic diagram of analytical model for aggregate structure.
Figure 4
Figure 4
Histogram of unconfined compressive strength of sand-gel specimens.
Figure 5
Figure 5
Unconfined compressive strength of sand-gel specimens under water immersion.
Figure 6
Figure 6
Unconfined compressive strength of hydrogel specimens under water immersion.
Figure 7
Figure 7
Volumetric shrinkage of hydrogel specimens.
Figure 8
Figure 8
Cohesion of sand-gel specimens.
Figure 9
Figure 9
Internal friction angle of sand-gel specimens.
Figure 10
Figure 10
Cohesion and internal friction angle for changing axial strain of sand-gel specimens (silica concentration: 9%).
Figure 11
Figure 11
Cohesion and internal friction angle for changing axial strain of sand-gel specimens (silica concentration: 12%).
Figure 12
Figure 12
Main stress difference, volumetric strain, cohesion, and internal friction angle for changing axial strain of sand-gel specimens.
Figure 13
Figure 13
Cohesion and internal friction angle for changing pore ratio on sand-gel specimens with silica concentration of 12%, material age of 28 days, and σ3 = 49 kN/m2.
Figure 14
Figure 14
Cohesion and internal friction angle for changing pore ratio on sand-gel specimens with silica concentration of 12%, material age of 28 days, and σ3 = 98 kN/m2.
Figure 15
Figure 15
Cohesion and internal friction angle for changing pore ratio on sand-gel specimens with silica concentration of 12%, material age of 28 days, and σ3 = 196 kN/m2.
Figure 16
Figure 16
Glass capillary at curing temperature of 60 °C and material age of 28 days.
Figure 17
Figure 17
Scattering curves of hydrogel specimens.
Figure 18
Figure 18
Changes over time in primary diameter (size) of hydrogel specimens.
Figure 19
Figure 19
Changes over time in correlation length of hydrogel specimens.
Figure 20
Figure 20
Changes over time in fractal dimension of hydrogel specimens.
Figure 21
Figure 21
Molecular structure model of hydrogel specimens cured at 60 °C for 1 day.
Figure 22
Figure 22
Molecular structure model of hydrogel specimens cured at 60 °C for 7 days.
Figure 23
Figure 23
Molecular structure model of hydrogel specimens cured at 60 °C for 28 days.
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References

    1. Karol R.H. Chemical Grouting and Soil Stabilization. 3rd ed. CRC Press; Boca Raton, FL, USA: 2003. Revised and expanded.
    1. Varol A., Dalgıç S. Grouting applications in the Istanbul metro, Turkey. Tunn. Undergr. Space Technol. 2006;21:602–612. doi: 10.1016/j.tust.2005.11.002. - DOI
    1. Kazemian S., Huat B.B., Arun P., Barghchi M. A review of stabilization of soft soils by injection of chemical grouting. Aust. J. Basic Appl. Sci. 2010;4:5862–5868.
    1. Anagnostopoulos C.A., Papaliangas T., Manolopoulou S., Dimopoulos T. Physical and mechanical properties of chemically grouted sand. Tunn. Undergr. Space Technol. 2011;26:718–724. doi: 10.1016/j.tust.2011.05.006. - DOI
    1. Liang Y., Sui W., Qi J. Experimental investigation on chemical grouting of inclined fracture to control sand and water flow. Tunn. Undergr. Space Technol. 2019;83:82–90. doi: 10.1016/j.tust.2018.09.038. - DOI

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