• Bio-mediated and Bio-inspired Geotechnics
• Sustainable cementitious materials
• Bio-cement based soil improvement technology (MICP, EICP and CPC)
• Slope stability and near-surface preservation
• Stabilization of organic and peat soils

Journals (peer-reviewed): 

1. Gowthaman, S., Yamamoto, M., Nakashima, K., Ivanov, V. and Kawasaki, S. “Calcium phosphate biocement using bone meal and acid urease: An eco-friendly approach for soil improvement”. J. Clean. Prod. 128782, 2021. https://doi.org/10.1016/j.jclepro.2021.128782
2. Gowthaman, S., Mohsenzadeh, A., Nakashima, K. and Kawasaki, S. “Removal of ammonium by-products from the effluent of bio-cementation system through struvite precipitation”. Materials Today: Proceedings, 2021.   https://doi.org/10.1016/j.matpr.2021.09.013
3. Chen, M., Gowthaman, S., Nakashima, K., Komatsu, S. and Kawasaki, S. “Experimental Study on Sand Stabilization Using Bio-Cementation with Wastepaper Fiber Integration”. Materials. 14(18):5164, 2021.  https://doi.org/10.3390/ma14185164
4. Gowthaman. S., Chen, M., Nakashima, K. and Kawasaki, S. "Effect of Scallop Powder Addition on MICP Treatment of Amorphous Peat". Front. Environ. Sci. 9: 690376, 2021. https://doi.org/10.3389/fenvs.2021.690376
5. Gowthaman, S., Nakashima, K. & Kawasaki, S. "Durability analysis of bio-cemented slope soil under the exposure of acid rain". J Soils Sediments, 21, pp. 2831-2844, 2021. https://doi.org/10.1007/s11368-021-02997-w
6. Gowthaman, S., Nakashima, K. and Kawasaki, S. "Effect of wetting and drying cycles on the durability of bio-cemented soil of expressway slope", Int. J. Environ. Sci. Technol, 2021. https://doi.org/10.1007/s13762-021-03306-1
7. Chen, M., Gowthaman, S., Nakashima, K., Kawasaki, S. "Evaluating mechanical strength of peat soil treated by fiber incorporated bio-cementation", GEOMATE, 20(78), pp.121-127. 2021.  https://doi.org/10.21660/2021.78.Gx162
8. Mohsenzadeh, A., Aflaki, E., Gowthaman, S., Nakashima, K., Kawasaki, S., Ebadi, T. "A two-stage treatment process for the management of produced ammonium by-products in ureolytic bio-cementation process", Int. J. Environ. Sci. Technol, 2021.  https://doi.org/10.1007/s13762-021-03138-z
9. Imran, M.A., Gowthaman, S., Nakashima, K., Kawasaki, S. "The Influence of the Addition of Plant-Based Natural Fibers (Jute) on Biocemented Sand Using MICP Method", Materials, 13(18): 4198, 2020.  https://doi.org/10.3390/ma13184198
10. Gowthaman, S., Nakashima, K., and Kawasaki, S. "Freeze-Thaw Durability and Shear Responses of Cemented Slope Soil Treated by Microbial Induced Carbonate Precipitation", Soils and Foundations, 60(4), pp.840-855, 2020.  https://doi.org/10.1016/j.sandf.2020.05.012.
11. Gowthaman, S., Iki, T., Nakashima, K., Ebina, K., and Kawasaki, S. "Feasibility study for slope soil stabilization by microbial induced carbonate precipitation (MICP) using indigenous bacteria isolated from cold subarctic region", SN Applied Sciences, 1(1480), 2019. https://doi.org/10.1007/s42452-019-1508-y.
12. Gowthaman, S., Mitsuyama, S., Nakashima, K., Komatsu, M., and Kawasaki, S. "Biogeotechnical approach for slope soil stabilization using locally isolated bacteria and inexpensive low-grade chemicals: A feasibility study on Hokkaido expressway soil", Japan. Soils and Foundations, 59(2), pp.484-499, 2019.  https://doi.org/10.1016/j.sandf.2018.12.010.
13. Gowthaman, S., Mitsuyama, S., Nakashima, K., Komatsu, M., and Kawasaki, S. "Microbial induced slope surface stabilization using industrial-grade chemicals: a preliminary laboratory study", GEOMATE, 17(60), pp.110-116, 2019.  https://doi.org/10.21660/2019.60.8150.
14. Gowthaman, S., Nakashima, K., Kawasaki, S. "A State-of-the-Art Review on Soil Reinforcement Technology Using Natural Plant Fiber Materials: Past Findings, Present Trends and Future Directions", Materials, 11(553), 2018. https://doi.org/10.3390/ma11040553.
15. Gowthaman, S. and Nasvi, M.C.M. "Three - dimensional Numerical Simulation and Validation of Load-settlement Behaviour of a Pile Group under Compressive Loading", Engineer: Journal of the Institution of Engineers, Sri Lanka, 51(1), pp.9-21, 2018.  http://doi.org/10.4038/engineer.v51i1.7283.
16. Gowthaman, S., Nasvi, M.C.M. and Krishnya, S. "Numerical Study and Comparison of the Settlement Behaviours of Axially Loaded Piles using Different Material Models", Engineer: Journal of the Institution of Engineers, Sri Lanka. 50(2), pp.1-10, 2017.  http://doi.org/10.4038/engineer.v50i2.7247.
17. Gowthaman, S., Krishnya, S. and Nasvi, M.C.M. "Effect of Salinity on Mechanical Behaviour of Well Cement: Application to Carbon Capture and Storage Wells", Engineer: Journal of the Institution of Engineers, Sri Lanka. 49(1), pp.21-29, 2016.  http://doi.org/10.4038/engineer.v49i1.6915.

Conference/ symposium papers (reviewed):

1. Gowthaman, S., Mohsenzadeh, A., Nakashima, K., Nakamura, H., and Kawasaki, S. "Evaluation on the Performance of MICP Treated Slope Soil Under Acid Rain Environment. Proceedings of 10th International Conference on Geotechnique, Construction Materials and Environment, Melbourne, Australia, Nov 2020.
2. Chen, M., Gowthaman, S., Nakashima, K., and Kawasaki, S. Mechanical Strength of Peat Soil Treated by Fiber Incorporated Microbial Cementation. Proceedings of 10th International Conference on Geotechnique, Construction Materials and Environment, Melbourne, Australia, Nov 2020.
3. Gowthaman, S., Nayanthara, P.G.N., Nakashima, K., Kawasaki, S., and Sato, A. Mechanical Strength of Organic Soil Treated by Fiber Incorporated Microbial Cementation. Proceedings of 1st International Conference on Microbial Biotechnology in Construction Materials and Geotechnical Engineering, Nanjing, China, Nov 2020.
4. Gowthaman, S., Nakashima, K., Nakamura, H., and Kawasaki, S. Influence of wet-dry and freeze-thaw cycles on the physical and mechanical properties of MICP treated slope soil. Proceedings of 54th US Rock Mechanics/Geomechanics Symposium, ARMA (American Rock Mechanics Association), Colorado, United States, June 2020.
5. Gowthaman, S., Nakashima, K., Ebina, K., and Kawasaki, S. Bio-cementation for Slope Soil Stabilization against Surface Erosion: A Bench-scale Preliminary Investigation. Proceedings of 53rd US Rock Mechanics/Geomechanics Symposium, ARMA (American Rock Mechanics Association), New York, United States, June 2019.
6. Gowthaman, S., Mitsuyama, S., Nakashima, K., Komatsu, M., and Kawasaki, S. Bio-Inspired Stabilization of Embankment Soil Mediating Psychrobacillus Sp. and Low-Grade Chemicals: Preliminary Laboratory Investigation. Proceedings of 8th Int. Conference on Geotechnique, Construction Materials and Environment, Kuala Lumpur, Malaysia, Nov 2018.
7. Gowthaman, S., Mitsuyama, S., Nakashima, K., Kawasaki, S., Komatsu, M. Quantifying the Solidification Effect of Biogrouted Soil Using Native Bacteria: Initial Investigation for Slope Soil Stabilization. Biomediated and Bioinspired Geotechnics (B2G-2018), Atlanta, United States, Sept 2018.
8. Gowthaman, S., Nakashima, K., Ebina, K., and Kawasaki, S. Experimental Optimization of Biocement Formation: Alternative Countermeasure for Surface Erosion of Cut Slope. Proceedings of International symposium on Earth Resources Management and Environment (ISERME), Colombo, Sri Lanka, Aug 2018, pp.97-103.
9. Gowthaman, S., and Nasvi, M.C.M. Numerical Study of Settlement Behaviour of Axially Loaded Piles Used for High-Rise Building, Proceedings of High-rise buildings and Geotechnical Engineering applications, 7th International Conference of Sustainable Built Environment, Kandy, Sri Lanka, Dec 2016.
10. Gowthaman, S., Krishnya, S. and Nasvi, M.C.M. Mechanical behavior of well cement cured in saline water: an application to oil and gas wells, Proceedings of 18th annual conference of SLGS (Sri Lankan Geotechnical Society), Colombo, Sri Lanka, Dec 2015, pp.53-56.

Book Chapters

1. Gowthaman, S., Chen, M., Nakashima, K., Komatsu, S. and Kawasaki, S. “Biocementation technology for stabilization/solidification of organic peat”, In: Tsang, D., Wang, L. (eds) Low Carbon Stabilization and Solidification of Hazardous Wastes (1^st Edition), Elsevier. 2021. https://doi.org/10.1016/B978-0-12-824004-5.00019-0
2. Chen M., Gowthaman S., Nakashima K., Komatsu S., Kawasaki S. (2021) "Used Paper Fibers for Sustainably Enhancing the MICP Stabilization of Sand". In: Kim S.S., Moghal A.A.B., Yao J. (eds) Advances in Urban Geotechnical Engineering. GeoChina 2021. Sustainable Civil Infrastructures. Springer, Cham. https://doi.org/10.1007/978-3-030-80152-6_5
3. Gowthaman S., Nawarathna T.H.K., Nayanthara P.G.N., Nakashima K., Kawasaki S. "The Amendments in Typical Microbial Induced Soil Stabilization by Low-Grade Chemicals, Biopolymers and Other Additives: A Review", In: Achal V., Chin C.S. (eds) Building Materials for Sustainable and Ecological Environment, Springer, Singapore. 2021. https://doi.org/10.1007/978-981-16-1706-5_4
4. Gowthaman S., Nakashima K., Nakamura H., Kawasaki S. "Experimental Study on Strengthening Near-Surface of Slopes Using Bio-grouting Technique". In: Hazarika H., Madabhushi G.S.P., Yasuhara K., Bergado D.T. (eds) Advances in Sustainable Construction and Resource Management. Lecture Notes in Civil Engineering, 144. Springer, Singapore, 2021. https://doi.org/10.1007/978-981-16-0077-7_64

• Best Presentation Award (2021) for the paper presented at International Symposium on Construction Resources for Environmentally Sustainable Technologies, Fukuoka, Japan.
  
• Shining Star Award (2018), Biotechnology for Resources Engineering, Hokkaido University, Japan.
  
• GEOMATE Best Research Paper Award (2018) in 8th International Conference on Geotechnique, Construction Materials and Environment Kuala Lumpur, Malaysia.
  
• MEXT (Japanese Government Scholarship) scholar (2017-2020)

• Associate Member of IESL (Institution of Engineers Sri Lanka) (2016 - date)
• Associate Engineer in ECSL (Engineering Council, SL) (2020 - date)
• Regular Member, GEOMATE International Society, Japan (2018-2019)
• Vice President of HUISA (Hokkaido University International Students Association) (2019-2020)
• Student Counsellor, Faculty of Technology, University of Jaffna (2016-2017)
• Secretary of Civil Engineering Society, University of Peradeniya (2014-2015)