Soil Mix Cutoff Wall Materials with Microcapsule-Based Self-Healing Grout
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 147, Issue 11
Abstract
Over the last three decades, cutoff walls using soil mix technology have been developed and deployed to deliver in situ containment of contaminated sites. The aggressive contaminated soil environment imposes significant long-term stresses on wall materials, and underground cracking is very difficult to detect and can compromise the integrity of walls. A recent relevant development is the concept of self-healing materials that can be triggered by damage and self-heal without the need for external intervention. This laboratory study developed, for the first time, a microcapsule-based self-healing soil mix cutoff wall material and demonstrated its performance in the healing processes, recovery of compressive strength, and hydraulic conductivity. The developed microcapsule-based cementitious grout was mixed with a sand soil using a laboratory-scale auger, and the embedded microcapsules were triggered upon cracking and released a sodium silicate cargo that healed the cracks. Micro–computed tomography (micro-CT) scan analysis verified the good survivability and uniform distribution of the microcapsules during the auger mixing process. Scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM-EDX) and thermogravimetric analysis (TGA) revealed that the released sodium silicate microcapsule cargo reacted with the cementitious matrix to produce healing products in the form of calcium silicate hydrates. The microcapsule-containing posthealing specimens regained 44% of initial compressive strength and showed a recovered hydraulic conductivity only slightly higher than that of the undamaged specimens. The results demonstrated the great potential of microencapsulated sodium silicate as a self-healing agent for cement mixed soil, which could provide more resilient and reliable soil mix cutoff walls.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
Support from the Engineering and Physical Sciences Research Council (EPSRC)-funded program Resilient Materials for Life (RM4L) (Grant No. EP/P02081X/1) is gratefully appreciated. The first author would also like to acknowledge support from the China Scholarship Council and Cambridge Trust for his Ph.D. study.
References
Aldea, C.-M., S. P. Shah, and A. Karr. 1999. “Effect of cracking on water and chloride hydraulic conductivity of concrete.” J. Mater. Civ. Eng. 11 (3): 181–187. https://doi.org/10.1061/(ASCE)0899-1561(1999)11:3(181).
Al-Tabbaa, A., P. Barker, and C. W. Evans. 2011. “Soil mix technology for land remediation: Recent innovations.” Proc. Inst. Civ. Eng. Ground Improv. 164 (3): 127–137. https://doi.org/10.1680/grim.2011.164.3.127.
Al-Tabbaa, A., and C. W. Evans. 1999. “Laboratory-scale soil mixing of a contaminated site.” Proc. Inst. Civ. Eng. Ground Improv. 3 (3): 119–134. https://doi.org/10.1680/gi.1999.030303.
Al-Tabbaa, A., C. W. Evans, C. J. Wallace. 1998. “Pilot in situ auger mixing treatment of a contaminated site. Part 2: Site trial.” Proc. Inst. Civ. Eng. Geotech. Eng. 131 (2): 89–95.
Al-Tabbaa, A., and M. J. Harbottle. 2015. “Self-healing materials and structures for geotechnical and geo-environmental applications.” In Proc., XVI ECSMGE, 589–594. London: Institution of Civil Engineers.
Al-Tabbaa, A., C. Litina, P. Giannaros, A. Kanellopoulos, and L. Souza. 2019. “First UK field application and performance of microcapsule-based self-healing concrete.” Constr. Build. Mater. 208 (May): 669–685. https://doi.org/10.1016/j.conbuildmat.2019.02.178.
Arnold, M., K. Beckhaus, and U. Wiedenmann. 2011. “Cut-off wall construction using Cutter Soil Mixing: A case study.” Geotechnik 34 (1): 11–21. https://doi.org/10.1002/gete.201000021.
Bureau of Reclamation. 2014. Design standards no. 13: Embankment dams. Washington, DC: Bureau of Reclamation.
Cao, B., J. Chen, and A. Al-Tabbaa. 2021. “Crack-resistant cement–bentonite cut-off wall materials incorporating superabsorbent polymers.” Can. Geotech. J. 58 (6): 800–810. https://doi.org/10.1139/cgj-2020-0181.
Cermak, J., J. Evans, and G. J. Tamaro. 2012. “Evaluation of soil-cement-bentonite wall performance-effects of backfill shrinkage.” In Proc., Grouting and Deep Mixing 2012, 502–511. Reston, VA: ASCE.
Chen, J. 2020. “Development and performance of self-healing and self-immune soil-cement systems subjected to freeze-thaw cycles.” Ph.D. dissertation, Dept. of Engineering, Univ. of Cambridge.
Chitambira, B. 2000. “Innovative and sustainable applications of soil-mixed columns.” M.Phil thesis, Dept. of Engineering, Univ. of Cambridge.
De Rooij, M. R., K. Van Tittelboom, N. De Belie, and E. Schlangen. 2013. Self-healing phenomena in cement-based materials: State-of-the-art report of RILEM technical committee 221-SHC: Self-healing phenomena in cement-based materials. New York: Springer.
Evans, J. C., and S. A. Jefferis. 2014. “Volume change characteristics of cutoff wall materials.” In Proc., 7th Int. Congress on Environmental Geotechnics, 10–14. Barton, Australia: Institution of Engineers Australia.
Garvin, S. L., and C. S. Hayles. 1999. “The chemical compatibility of cement–bentonite cut-off wall material.” Constr. Build. Mater. 13 (6): 329–341. https://doi.org/10.1016/S0950-0618(99)00024-0.
Giannaros, P., A. Kanellopoulos, and A. Al-Tabbaa. 2016. “Sealing of cracks in cement using microencapsulated sodium silicate.” Smart Mater. Struct. 25 (8): 084005. https://doi.org/10.1088/0964-1726/25/8/084005.
Hewlett, P., and M. Liska. 2019. Lea’s chemistry of cement and concrete. 5th ed. Oxford, UK: Butterworth-Heinemann.
Huang, H., G. Ye, and D. Damidot. 2013. “Characterization and quantification of self-healing behaviors of microcracks due to further hydration in cement paste.” Cem. Concr. Res. 52 (Oct): 71–81. https://doi.org/10.1016/j.cemconres.2013.05.003.
Huang, H., G. Ye, C. Qian, and E. Schlangen. 2016. “Self-healing in cementitious materials: Materials, methods and service conditions.” Mater. Des. 92 (Feb): 499–511. https://doi.org/10.1016/j.matdes.2015.12.091.
Kanellopoulos, A., P. Giannaros, and A. Al-Tabbaa. 2016. “The effect of varying volume fraction of microcapsules on fresh, mechanical and self-healing properties of mortars.” Constr. Build. Mater. 122 (Sep): 577–593. https://doi.org/10.1016/j.conbuildmat.2016.06.119.
Kanellopoulos, A., P. Giannaros, D. Palmer, A. Kerr, and A. Al-Tabbaa. 2017. “Polymeric microcapsules with switchable mechanical properties for self-healing concrete: Synthesis, characterisation and proof of concept.” Smart Mater. Struct. 26 (4): 045025. https://doi.org/10.1088/1361-665X/aa516c.
Mao, W., C. Litina, and A. Al-Tabbaa. 2020. “Development and application of novel sodium silicate microcapsule-based self-healing oil well cement.” Materials 13 (2): 456. https://doi.org/10.3390/ma13020456.
Nejad, B. G., T. Osborne, and J. P. Carter. 2017. “Forensic investigation of a slurry wall failure: A case study.” In Proc., Grouting 2017, 513–522. Reston, VA: ASCE.
O’Connor, D. 2016. “Performance of soil mix technology low hydraulic conductivity reactive in-ground barrier walls for contaminated land applications.” Ph.D. dissertation, Dept. of Engineering, Univ. of Cambridge.
Osman, A. 2007. “Durability and mechanical properties of deep-mixed clays.” Ph.D. dissertation, Dept. of Engineering, Univ. of Cambridge.
Porbaha, A. 1998. “State of the art in deep mixing technology: Part I. Basic concepts and overview.” Proc. Inst. Civ. Eng. Ground Improv. 2 (2): 81–92. https://doi.org/10.1680/gi.1998.020204.
Reinhardt, H. W., and M. Jooss. 2003. “Hydraulic conductivity and self-healing of cracked concrete as a function of temperature and crack width.” Cem. Concr. Res. 33 (7): 981–985. https://doi.org/10.1016/S0008-8846(02)01099-2.
Scrivener, K., R. Snellings, and B. Lothenbach. 2016. Vol. 540 of A practical guide to microstructural analysis of cementitious materials. Boca Raton, FL: CRC Press.
Souza, L., and A. Al-Tabbaa. 2018. “Microfluidic fabrication of microcapsules tailored for self-healing in cementitious materials.” Constr. Build. Mater. 184 (Sep): 713–722. https://doi.org/10.1016/j.conbuildmat.2018.07.005.
Van Tittelboom, K., et al. 2016. “Comparison of different approaches for self-healing concrete in a large-scale lab test.” Constr. Build. Mater. 107 (Mar): 125–137. https://doi.org/10.1016/j.conbuildmat.2015.12.186.
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© 2021 American Society of Civil Engineers.
History
Received: Oct 28, 2020
Accepted: Jul 27, 2021
Published online: Aug 30, 2021
Published in print: Nov 1, 2021
Discussion open until: Jan 30, 2022
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