Reza Hedayat

Assistant Professor, Civil and Environmental Engineering

Reza HedayatDr. Hedayat’s research interests focus on the mechanical and geophysical characterization of geomaterials, rock and fracture mechanics, applied geophysics and wave propagation, laboratory earthquakes, hydro-mechanical properties of shales, and ground-support interaction in tunnels. Dr. Hedayat’s research utilizes geophysical methods and wave analysis to observe what is happening inside the materials with the aim of understanding multi-scale physical processes like slip, failure, earthquake, and fracturing. Dr. Hedayat’s research has focused on active geophysical monitoring of shear failure along rock joints using compressional and shear waves and resulted in the identification of geophysical precursors prior to the failure. Dr. Hedayat’s research strives to develop a better understanding of fracturing and flow in geomaterials and aims to bridge the gap between laboratory studies and field applications through performing multiscale experiments and developing theoretical and numerical models. Dr. Hedayat’s future research will involve multiscale experimental study of soils and rocks, non-destructive characterization of ground condition in tunnels, laboratory investigation of hydraulic fracturing, and fluid flow in porous and fractured media.

Dr. Hedayat’s teaching interests are in mechanics of materials, soil mechanics, foundations, earth retaining structures, rock mechanics, tunnels in hard rock, and fracture of geomaterials.


  • PhD Civil Engineering, Purdue University, 2013
  • MS Civil Engineering, Amirkabir University of Technology, 2009
  • BS Civil Engineering, Shiraz University, 2006

Selected Publications

  • Masoumi, H., Roshan, H., Hedayat, A., Hagan, PC. (2018). Scale/Size dependency of intact rock under point load and indirect tensile (Brazilian) testing. International Journal of Geomechanics. DOI: 10.1061/(ASCE)GM.1943-5622.0001103.
  • Hedayat, A., Haeri, H., Hinton, J., Masoumi, H., and Spagnoli, G. (2018).Geophysical signatures of shear induced damage and frictional processes on rock joint. Journal of Geophysical Research. DOI: 10.1002/2017JB014773.
  • Haeri, H., Sarfarazi, V., Shemirani, A.B., Hedayat, A. (2017). Experimental and numerical investigation of the center-cracked horseshoe disk method for determining the mode I fracture toughness of rock-like material. Rock Mechanics and Rock Engineering. DOI: 10.1007/s00603-017-1310-3.
  • Shemirani, A., Haeri, H., Sarfarazi, V., and Hedayat, A. (2017). A review paper about experimental investigations on failure behavior of non-persistent joint. Geomechanics and Engineering. 13, 535-570.
  • Sarfarazi, V., Haeri, H., Shemirani, A., Hedayat, A., and Hosseini, S. (2017). Investigation of ratio of TBM disc spacing to penetration depth in rocks with different tensile strengths using PFC2D. Computers and Concrete, 20(4), 429-437.
  • Hedayat, A., and Walton, G. (2017). Laboratory determination of rock fracture shear stiffness using seismic wave propagation and digital image correlation. Geotechnical Testing Journal, 40(10), 92-106. DOI: 10.1520/GTJ20160035.
  • Walton, G., Hedayat, A., Kim, E., and Labrie, D. (2017). Post-yield strength and dilatancy evolution across the brittle-ductile transition in Indiana limestone. Rock Mechanics and Rock Engineering. DOI: 10.1007/s00603-017-1195-1.
  • Haeri, H., Sarfarazi, V., Hedayat, A., Tabaroei, A. (2016). Effect of tensile strength of rock on tensile fracture toughness using experimental test and PFC2D simulation. Journal of Mining Science, 52(4), 647-661.
  • Haeri, H., Sarfarazi, V., Hedayat, A. (2016). Suggesting a new testing device for determination of tensile strength of concrete. Structural Engineering and Mechanics, 60(6), 939-952. DOI: 10.12989/sem.2016.60.6.939.
  • Haeri, H., Hedayat, A., Zhu, Z. (2016). Numerical simulation of hydraulic fracturing in circular holes. Computers and Concrete, 18(6), 1135-1151. DOI:
  • Haeri, H., Sarfarazi, V., Marji, M.F., Hedayat, A., Zhu, Z. (2016). Experimental and Numerical Study of Shear Fracture in Brittle Materials with Interference of Initial Double Cracks. Acta Mechanica Solida Sinica, 29(5), 555-566.
  • Hedayat, A., Pyrak-Nolte, L and Bobet, A. (2014). Precursors to shear failure of rock discontinuities. Geophysical Research Letters, 41, 5467-5475, doi: 10.1002/2014GL060848.
  • Hedayat, A., Pyrak-Nolte, L and Bobet, A. (2014). Detection and quantification of slip along non-uniform frictional discontinuities using digital image correlation. Geotechnical Testing Journal, 37 (5), doi: 10.1520/GTJ20130141.
  • Hedayat, A., Pyrak-Nolte, L and Bobet, A. (2014). Multi-modal monitoring of slip along frictional discontinuities. Rock Mechanics and Rock Engineering, 47(5), 1575-1587, doi: 10.1007/s00603-014-0588-7.
  • Fahimifar, A., Monshizadeh, F., Hedayat, A., and Vakilzadeh, A. (2010). Analytical solution for the excavation of circular tunnels in a visco-elastic Burger’s material under hydrostatic stress field. Tunnelling and Underground Space Technology, 25(4), 297-304, doi: 10.1016/j.tust.2010.01.002.
  • Fahimifar, A. and Hedayat, A. (2010). Elasto-plastic analysis in conventional tunnelling excavation. Proceedings of the ICE- Geotechnical Engineering, 163(1), 37-45, doi: 10.1680/geng.2010.163.1.37.

Honors and Awards

  • Future Leaders Program Membership, American Rock Mechanics Association, 2015
  • Rocha Medal Runner-up Certificate Award, International Society of Rock Mechanics, 2015
  • N.G.W. Cook Ph.D. Dissertation Award, American Rock Mechanics Association, 2014