Research Interests

• Rheology of suspensions
• Suspension flow in porous media
• Soil improvement
• Permeation grouting

Selected Publications

Journal Publications

1. Enhanced Estimate of Fracture Network Dimensions by Injection of Non-Newtonian Fluids (2023). Jaffal, H. and El Mohtar, C.S. Canadian Geotechnical Journal. doi:10.1139/cgj-2022-0369.
2. Geotechnical characterization of collapsible salty sands subjected to monotonic and cyclic loadings – A case study for areas with high seismicity (2023). Macedo, J., Sotelo, G., Orellana, S., Vergaray, L., Liu, F., Jaffal, H., El Mohtar, C. Soils and Foundations. doi:10.1016/j.sandf.2022.101252.
3. Implementing digital imaging for improved understanding of microfine cement grout permeation and filtration (2022). El Mohtar, C., Jaffal, H., Miller, A.K., & Ward, K. Geotechnical and Geological Engineering. Volume 40, Issue 9, Pages 4473-4485. doi: 10.1007/s10706-022-02164-z.
4. Experimental Investigation and Modeling of Mudcake Buildup Inside Fractures and the Resulting Fracture Isolation (2019). Jaffal, H. A., Gray, K. E., & El Mohtar, C. S. Society of Petroleum Engineers. doi:10.2118/198895-PA.
5. A Predictive Filtration Model Considering Mudcake Compressibility and non-Uniform Properties Profiles (2018). Jaffal, H. A., El Mohtar, C. S., Gray, K. E., Journal of Natural Gas Science and Engineering, Volume 55, Pages 174-181..
6. Wellbore Breakouts: Mohr-Coulomb Plastic Rock Deformation, Fluid Seepage, and Time-Dependent Mudcake Buildup (2018). Li, X., Jaffal, H. A., Feng, Y., El Mohtar, S., Gray, K. E., Journal of Natural Gas Science and Engineering, Volume 52, Pages 515-528.
7. Effect of compaction method on the undrained strength of fiber-reinforced clay (2018). Diab, A.A., Najjar, S.S., Sadek, S., Taha, H., Jaffal, H., Alahmad, M., Soils and Foundations, 58(2), 462–480. 8. Transferring innovative research into practical wisdom: the case of permeation grouting. El Mohtar, C.S., Yoon, J., Sangroya, R., and Jaffal, H., Innovative Infrastructure Solutions, 37(2), Dec. 2017.
8. Modeling of filtration and mudcake buildup: An experimental investigation. Jaffal, H. A., El Mohtar, C.S., and Gray, K. E., Journal of Natural Gas and Engineering, Vol. 38, pp 1- 11, Feb. 2016.
9. Design of Thick Plate Double-Tee Connections for Seismic Applications. Hantouche, E. and Jaffal, H. A., Practical Periodical on Structural Design and Construction, 2016, 21(4), 04016013.

Conference Proceedings

1. Cement Suspension Flow through Heterogeneous Porous Media. Jaffal, H. A., El Mohtar, C. S., Geo-Congress, Minneapolis, MN, 2020.
2. Geotechnical characterization of collapsible soils cemented by sand. Sotelo, G., Orellana, S., Macedo, J., Jaffal, H., Espinoza, G., Xu, Z., Stokoe, K., El Mohtar, C., 7 ICEGE, 2019.
3. A Laboratory Investigation into Time-Pressure Curves for Stable versus Unstable Grouts. Jaffal, H., Sangroya, R., El Mohtar, C.S., Proceedings of the Grouting 2017: Jet Grouting Deep Mixing and Diaphragm Walls Conference, July 9-12, 2017, Honolulu, Hawaii, GSP 288 pp.290-300.
4. Introducing a New Method for Measuring Internal Stability of Microfine Cement Grouts. El Mohtar, C.S., Miller, A.K., Jaffal, H., Proceedings of the Grouting 2017: Jet Grouting Deep Mixing and Diaphragm Walls Conference, July 9-12, 2017, Honolulu, Hawaii, GSP 288 pp.152-162.
5. Linear and Nonlinear Shear Moduli of Materials Associated with Heap Leach-Pad Mining. Keene A.K., Jaffal, H., Stokoe, K.H., El Mohtar, C.S., Reyes, A., Ayala, R., and Parra, D., Geotechnical Frontiers 2017, Orlando, Florida, March 12-15, 2017. GSP 281, pp. 160-170.
6. Using laboratory testing for designing an optimum field grout for the Millwoods Double Barrel Replacement project. El Mohtar, C.S., Brady, J., Sangroya, R., Jaffal, H., Kwan, W.S., Miller, A.K., Proceedings of the World Tunneling Congress, San Francisco, 2016.
7. On the dynamic properties of leached ore and mine waste. Parra, D., Reyes, A., Ayala, R., Keen, A., Stokoe, K., Jaffal, H., El Mohtar, C., Proceedings of Heap Leach Mining Solutions. Lima, Peru, 2016.
8. Evaluation of Pressure-Time Curves for Evaluating Permeation Grouting: A Laboratory Study. Jaffal, H., Sangroya, R., El Mohtar, C.S., Geo-structures Congress, Phoenix, AZ, 2016.
9. Bentonite Filtration in Permeation Grouting. Sangroya, R., El Mohtar, C.S., Jaffal, H., Geo-structures Congress, Phoenix, AZ, 2016.
10. Millwoods Double Barrel Replacement SEM Tunnel Project: A case study from Field to Lab to Field. El Mohtar, C.S., Brady, J., Sangroya, R., Jaffal, H., Geo-structures Congress, Phoenix, AZ, 2016.

Academic degrees

PhD, Civil Engineering, The University of Texas at Austin, USA, 2019
MS, Civil Engineering, The University of Texas at Austin, USA, 2016
BE, Civil and Environmental Engineering, The American University of Beirut, Lebanon, 2014

Professional Memberships

• ASCE Soil Properties and Modeling Committee
• ASCE Soil Improvement Committee