AsangaN Resume


Asanga S. Nanayakkara, Ph.D., P.E.

Houston, TX 77064                                281.961.3923                                                            

Geosciences Engineer

Expert knowledge and experience in Geomechanics & Geotechnical Engineering, Hydraulic fracture diagnostics, Coupled numerical simulations & modelling, Finite Element & Finite Difference simulations (ABAQUS, FLAC, GeoStudio, SEEPW, SLOPEW), Surface & subsurface deformation induced by injection operations such as waste disposal, Carbon Capture and Storage (CCS) and SAGD, Reservoir monitoring, and Oil & Gas. Highly computer literate, including developing algorithms and programming fully functional scientific software applications with user interfaces (ArcGIS, MATLAB, Fortran, C++, Visual Basic, Maple, STAAD.Pro, AutoCAD & AutoLISP, MicroStations, MS Office, HEC-HMS, HEC-RAS, HEC-RAS 2D, HEC-GeoHMS, HEC-GeoRAS). My areas of expertise also include: Soil & Rock Mechanics, Geophysics, Optimization & Inverse problems, Microdeformation & Tiltmeter Technology, Hydrologic & Hydraulics Engineering, Civil & Structural Engineering.

Experience in managing large projects, charting a successful path to completion of novel and demanding projects on time. Leading and mentoring analysts, providing guidance and conducting training classes.

Ability to function in a multi-disciplinary capacity and to develop and validate new technologies. Finding innovative solutions to challenging problems. Strong analytical skills. Ability to self-learn any software quickly. Ability to deliver high quality results under tight deadlines. Excellent written and verbal communication skills. Ability to work independently and as a part of a team. Have legal authorization to work for any employer in the United States of America and Canada.


  • Doctor of Philosophy, Civil Engineering, University of Calgary, AB, Canada
  • Specialization: Geotechnical Engineering, GPA: 3.82
  • Master of Science, Civil Engineering, University of Moratuwa, Sri Lanka
  • Specialization: Structural Engineering, GPA: 4.00
  • Bachelor of Science, Civil Engineering, University of Moratuwa, Sri Lanka
  • First class honors, GPA: 3.81


  • Registered Professional Engineer in Texas

Professional Experience

RJN ENGINEERING, INC., Houston, TX                                                                            

Senior Engineer (2016 - present)

  • Business development and civil works designs - Hydrology and Hydraulics (H&H) analysis, Storm water drainage & detention system design, Flood plain fill mitigation plans, Utility layouts, Paving plans etc.


Pinnacle – A Halliburton Service, Houston, TX, and Calgary, AB

Senior Geosciences Professional (2009-2015)

  • Conducted research & development work related to Geomechanics and Fracture Diagnostics
  • Developed algorithms and programmed fully functional software application with user interface
  • Conducted training sessions for analysts
  • Subject matter expert (SME) and global lead for Fracture Diagnostics/Microdeformation technology, collaborating with project managers, business development managers, software developers and analysts to complete unique and novel projects
  • Managed large hydraulic fracture diagnostics projects in shale, CBM etc., providing guidance to analysts, project managers, business development managers and field personnel, finalizing results/presentations, reviewing reports, and answering clients’ questions
  • Developed new product named as Stimulated Reservoir Characterization (SRC) used to map and characterize stimulated reservoir area using surface tiltmeter measurement. Developed feasibility evaluation methodologies for SRC, evaluating a large number of client projects and providing recommendations

Asanga S. Nanayakkara              Page Two


Weatherford Canada Partnership, Calgary, AB

Geomechanics Analyst, Advanced Geotechnology (2008)

  • Conducted numerical modeling of acid gas injection using FLAC (numerical simulation software based on finite difference method), producing a full report based on results.
  • Reviewed soil and rock lab testing reports, involved in material parameter estimation for simulations.


University of Calgary, Calgary, AB

Research Assistant (Geotechnical Engineering), Department of Civil Engineering (2002 – 2008)

  • Conducted research and development work related to geomechanics of surface and subsurface deformation induced by injection operations such as waste disposal, Carbon Capture and Storage (CCS) and SAGD
  • Created algorithms to determine reservoir volumetric deformation using a limited number of surface deformation measurements by solving an ill-posed inverse problem
  • Introduced set of methods to obtain quick estimates of maximum height, maximum gradient, and propagation distance of surface heave induced by reservoir volumetric expansion, used to determine suitable layouts for placing surface deformation measuring tools such as tiltmeters
  • Conducted fully coupled finite element simulations using ABAQUS to simulate geo-hydro-mechanical response induced by subsurface fluid injection operations such as CCS, SAGD, and waste disposal, producing reports and presenting results in conferences


University of Moratuwa, Sri Lanka

Research Assistant (Structural Engineering), Department of Civil Engineering (2000 – 2001)


A.G.S.A. Nanayakkara Associates (Pvt) Ltd., Sri Lanka

Civil Engineer (1998 – 1999)


Central Engineering Consultancy Bureau, Sri Lanka

Civil Engineer (Intern) (1997)


Professional Development

  • FRACPRO Software Training, Pinnacle – A Halliburton Service, Houston, TX, 2015
  • Fundamentals of Well Completions, PEICE training course, Houston, TX,2014
  • Hydraulic Fracturing - Design and Treatment, SPE training course, The Woodlands, TX, 2012
  • Hydraulic Fracturing / Pressure Analysis, SPE training course, San Antonio, TX, 2012
  • Geotechnical Modeling workshop, Geo-slope International, Calgary, AB, 2003


Courses Taken

Fundamentals of Soil Behavior, Applied Geotechnical Engineering, Case Studies in Geotechnical Engineering, Constitutive Law for Geomaterials, Theory and Application of the Finite Element Method, Numerical Methods of Modeling Geomaterials (finite element theory related to fully coupled reservoir rock-fluid systems included), Geotechnical Engineering and Geology, Structural Analysis, Design of Structural Elements (Steel, Concrete, Timber and Masonry), Analysis of Cylindrical Tanks with Spherical Roofs, Mechanics of Materials, Surveying and Transportation Engineering, Hydraulics and Environmental Engineering, Building Construction and Estimation, Construction Processes & Planning, Construction Management and Systems Engineering, Industrial Economics & Management, Mathematics.


Asanga S. Nanayakkara          Page Three

Teaching Experience

University of Calgary, Calgary, AB, Canada                                                   

Teaching Assistant, Department of Civil Engineering (2002-2004)

University of Moratuwa, Sri Lanka                                                             

Adjunct Instructor, Department of Civil Engineering (2000-2001)


Publications and Research Contributions

Journal and Conference Papers

  • Nanayakkara, A.S., Roadarmel, W.H., Marsic S. D. 2015, “Characterizing the Stimulated Reservoir with a Hydraulic Deformation Index Using Tiltmeter-Based Surface Microdeformation” Presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, TX, Feb 3-5
  • Nanayakkara, A.S., Wong, R.C.K. 2012, “A New approach to infer reservoir dilation using a limited number of tiltmeter measurements” Presented at 21st Canadian Rock Mech. Symposium, Edmonton, AB, May 5-9
  • Astakhov, D.K., Roadarmel, W.H., Nanayakkara, A.S. 2012, “A New method of characterizing the stimulated reservoir volume using tiltmeter-based surface microdeformation measurements”, Presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, TX, Feb 6-8
  • Nanayakkara, A.S., Wong, R.C.K. 2010, “Using surface deformation to estimate reservoir dilation: Strategies to improve accuracy”, Journal of Canadian Petroleum Technology, 49(1): 49-60. This paper also presented at the Canadian International Petroleum Conference / SPE Gas Technology Symposium, Calgary, June 17-19, 2008
  • Nanayakkara, A.S., Wong, R.C.K, 2009. “How far does surface heave propagate? A discussion on analytical and numerical modeling of the surface heave induced by subsurface fluid injection”, KSCE Journal of Civil Eng., 13(4):297-303. Paper also presented at 12th International Conference of International Association for Computer Methods and Advances in Geomechanics, Goa, India, Oct 1-6,2008
  • Nanayakkara, A.S., Wong, R.C.K., 2007. “Surface and subsurface vertical displacements and reservoir dilation induced by injection operations”, 60th Canadian Geotechnical Conference and 8th Joint CGS / IAH-CNC Groundwater Conference, Ottawa, Oct 21-24
  • Nanayakkara S.M.A., Nanayakkara, A.S., 2006. “New Composite Construction Material for Low Cost Underground Water Tanks”, Engineer Journal, Institute of Engineers, Sri Lanka, Vol. 39, No.4, pp 26-36

Professional Reports Submitted to Alberta Energy Research Institute (AERI)

  • Nanayakkara, A.S., Wong, R.C.K., 2005 – 2007. “Geomechanics-reservoir processes of waste injection (disposal) into unconsolidated formations”, Agreement No. 1440, Alberta Innovation and Science, Energy Research and Development, Alberta Energy Research Institute
  • Surface heave curve fitting using tiltmeter data – (2007)
  • Subsurface deformation characteristic estimation using surface deformation measurements by solving an ill-posed inverse problem, using Tikhonov regularization techniques – (2007)
  • Development of a new equation to represent three-dimensional surface heave profile and surface heave determination by applying optimization techniques to tiltmeter data – (2006)
  • Investigation of surface heave characteristics and geo-hydro-mechanical response in a clay seam embedded in a shale overburden, induced by subsurface fluid injection, using ABAQUS – (2005)

Progress Reports of Ph.D. Research, Department of Civil Engineering, University of Calgary, Calgary, AB, Canada

  • Nanayakkara, A.S., 2003. “Numerical modeling of “Biot” consolidation”
  • Nanayakkara, A.S., 2003. “Investigation of geo-mechanical effects due to subsurface injection by poro-elastic fully coupled analysis”
  • Nanayakkara, A.S., 2002. “Mathematical modeling of non-linear soil behavior”

Contact Information