Stephen Bratz, P.E.

Stephen joined Protection Engineering Consultants (PEC) in April of 2019. He holds a Master of Science degree in Structural Engineering from the University of Texas at San Antonio, where he researched the effects of welding on high mast illumination poles using the Abaqus Welding Interface (AWI) in his thesis. He also earned a Bachelor of Science degree in Physics from Texas Lutheran University.

Stephen provides support for design projects for blast and impact resistance of structures and glazing systems. In addition, he supports research efforts focused on the response of structures and construction materials subjected to blast loading and other extreme events. He has experience with MATLAB and various finite element software tools such as Abaqus and SAP2000.

Stephen will be supporting PEC and our clients on both research and design efforts, and can be contacted at 512-380-1988 x325 or


MS in Civil/Structural Engineering | University of Texas at San Antonio | 2017

BS in Physics | Texas Lutheran University | 2015

Brandon R. Kehl, CPP

Brandon Kehl has more than twenty (20) years of experience providing strategic leadership and counsel in security and safety for public and private organizations. Brandon joined Protection Engineering Consultants (PEC) in February of 2019 and currently serves as a Senior Security Consultant, managing and supporting projects focused on protecting people and assets.

Brandon is experienced in developing client-centered, comprehensive protection strategies that incorporate appropriate risk-reduction initiatives without sacrificing the established workplace culture. Brandon has held several leadership roles in security industry associations throughout his professional career, authoring many physical security policies, procedures, basic and advanced security manuals.

Brandon has served as an independent security consultant in several industry sectors, leading the design, development, and implementation of security initiatives ranging from simple policy changes or staff training to advanced electronic detection systems to identify potential incidents before they occur. Brandon has successfully facilitated threat, risk, and vulnerability assessments for many clients, where he identified the specific local and non-geographical threats and recommended measures to reduce the risk or impact of those threats.

Certifications and Licenses

  • Board Certified in Security Management (CPP) [ASIS International]
  • Security Consultant License – State of Texas DPS

Committees and Professional Affiliations

  • Member of International Association of Professional Security Consultants (IAPSC)
  • Chairperson (2015-2017), International Association of Healthcare Security & Safety (IAHSS) | Council on Education & Training
  • Chairperson (2011), ASIS International (ASIS) | Greater KC Chapter
  • Past Vice Chair, International Association of Healthcare Security & Safety (IAHSS) | Council on Education & Training
  • Past Vice Chair, Past Treasurer, ASIS International (ASIS) | Greater KC Chapter
  • Member of ASIS International
  • Member of International Association Campus Law Enforcement Administrators (IACLEA)


B.S. in Criminal Justice | Park University | 2008

Krystal Johle

Krystal Johle joined Protection Engineering Consultants in 2017 as a Financial Analyst and now serves PEC as our Manager of Operations. At PEC, she has a wide range of responsibilities including, but not limited to, financial management, vendor management, project and proposal management, accounting/ERP system administrator, facility and operations management, financial reporting, and Government compliance and audit support.

Krystal graduated Magna Cum Laude with a Bachelor of Business Administration in Finance from Texas State University in San Marcos.

Marlon Bazan, Ph.D., P.E., S.E.

Dr. Marlon Bazan joined Protection Engineering Consultants as a Project Engineer in February 2009. He supports and manages design and research projects in broad areas of blast-resistant structures analysis and design.

Marlon has performed design projects subject to ATFP and explosive safety requirements for federal (GSA) and military (DoD) clients, and supports industrial and petrochemical clients with designs and upgrades to resist the effects of accidental explosions.

In addition to design, Marlon supports design tool development through the incorporation of analysis and design methodologies and related response criteria into the Corps of Engineer’s SBEDS (Single-Degree-of-Freedom Blast Effects Design Spreadsheet) program.  Recent efforts have added expanded structural component and retrofit capabilities to that tool.  His research projects have included a test program on shoring systems for urban search and rescue for the Department of Homeland Security (DHS) and investigation of the blast response of steel braced frame structures conducted by PEC for the US Department of State (DoS).

Marlon earned a bachelor’s degree in civil engineering from the National University of Engineering (Lima, Peru) and a MS and PhD in Structural Engineering from Northeastern University.  He is a frequent contributor to and instructor for PEC sponsored short courses.


  • Ph.D. in Structural Engineering | Northeastern University | 2008
  • M.S. in Structural Engineering | Northeastern University | 2004
  • B.S. in Civil Engineering | National University of Engineering (Lima, Peru) | 1999

Edward Conrath, P.E.

Ed Conrath, a long-time security engineering expert with the U.S. Army Corps of Engineers, joined Protection Engineering Consultants as Senior Principal in April 2008.

Assigned to the U.S. Army Corps of Engineers Protective Design Center from 1985 to 2008, Ed has been at the leading edge of protecting people and structures from the effects of terrorist attacks in the United States and around the world.  He is a leading analyst and developer of security design guidelines and has performed more than 100 building vulnerability assessments in the U.S. and over 20 countries throughout the world, including assessments in the high-threat environments of Iraq and Afghanistan.

Ed completed two rotational assignments in Baghdad, providing support to U.S. and coalition forces. In this capacity, he performed vulnerability assessments and worked with local architects and material vendors to produce blast-mitigating products locally, allowing for rapid and cost-effective protection of U.S. and Iraqi personnel. His work was profiled in the January 2004 Engineer Update published by the Corps of Engineers.

Ed has conducted post-blast investigations in Iraq, Kuwait and Saudi Arabia, and he provided support to U.S. federal agencies after the 1995 Oklahoma City bombing attack. He also served as a United Nations inspector in Baghdad following the 1991 Gulf War.

Prior to his security engineering duties, Ed worked as a structural engineer on the Air Launch Cruise Missile Support Facilities and on the Underground Munitions Storage Complex at Kirtland AFB in New Mexico.

A 1977 graduate of the University of Nebraska at Omaha, Ed holds a Bachelor of Science degree in Civil Engineering. He is a registered Professional Engineer in the state of Nebraska, a member of the Society of American Military Engineers (SAME), the American Society of Civil Engineers (ASCE), the local chapter of the American Concrete Institute (ACI), and ASTM International, for which he is the former committee chairman of F12 and continues to work as the subcommittee chairman for F12.10.

Michalis Hadjioannou, Ph.D., P.E.

Dr. Michalis Hadjioannou joined Protection Engineering Consultants as a Sr. Associate Engineer / Structural Analyst on June 1st, 2015.  Michalis received his undergraduate degree from the National Technical University of Athens and is licensed to practice civil engineering in Cyprus (Scientific and Technical Chamber (ETEK)).  He received his MS and PhD from The University of Texas at Austin, with a dissertation entitled “Large-Scale Testing and Numerical Simulations of Composite Floor Slabs Under Progressive Collapse Scenarios”, a research study focused on quantifying the contribution of steel-concrete composite floor slabs in mitigating progressive collapse of steel structures. The research was supported by full-scale tests and high-fidelity finite element models were validated against the experimental results.  Michalis is experienced with the LS-DYNA, ADINA, PLAXIS, ABAQUS, and SAP2000 numerical analysis tools, and will be supporting PEC and our clients on both research and design efforts. Contact Michalis at 512-380-1988 x307 or


  • Ph.D. in Civil Engineering | University of Texas at Austin | 2015
  • M.S. in Structural Engineering | University of Texas at Austin | 2012
  • B.S. in Civil Engineering | National Technical of Athens | 2010

Matt Barsotti

Matt Barsotti joined Protection Engineering Consultants in 2007, and he has 20 years of applied research, engineering, and data science experience. He currently leads the company’s efforts in engineering analytics, a focus area at the intersection of first-principles engineering analysis and cutting-edge data science. Matt’s technical interests span a broad range of disciplines, including modeling and simulation, data science, algorithm development, material characterization, large scale testing, debris modeling, etc. He routinely leads projects by assembling, managing, and collaborating with interdisciplinary teams of engineers and scientists from disparate fields. His clientele has included DARPA, National Academy of Science TRB/ACRP, DOS, US Army, US Air Force, US Marine Corps, DTRA, MDA, ERDC, TSWG, etc.

Since joining PEC, Matt has worked on a broad range of advanced research and development efforts. He has extensive experience in numerical modeling of soil materials subjected to high rate and explosive loads. His novel work resulted in a generalized sandy soil model capable of making high accuracy predictions for a broad range of explosive test cases with arbitrary degrees of pre-compaction and moisture content. He has developed multiple fast-running models (FRMs) for several applications, including explosively-loaded bridge cables, aircraft tire overruns in compressible soil media, glass and concrete fragment flyout, ground shock propagation, etc. He is a leading expert in the niche field of Engineered Materials Arrestor Systems (EMAS), which are installed at civil airports and employ crushable foam materials to arrest aircraft during emergency overruns.

His present efforts focus on cutting edge areas of development. In the area of artificial intelligence, he is developing software to automate the construction of physics-based models using genetic programming, which can evolve and discover equations that capture the underlying physics of various problems. In data analytics, he has led the development of improved statistical algorithms for modeling debris created during explosion events. And in testing, he is leading a development effort to employ high-powered laser ablation to test metals at very high strain rates.

Other areas of prior work have included • Machine Learning • Genetic Programming • Laser Ablation Testing • Spectral Analysis • Fast Running Models • Land Mine and Improvised Explosive Device (IED) • Penetration Mechanics • Pipeline Vulnerability • Bridge Cable Armor • Glass Hazard Analysis • Transparent Armor Spall • Eye Injury • Low Friction Vehicle Counter-mobility • Bolted Connection Modeling • Steel Triaxiality Modeling • Fluid Modeling • Tire Modeling • Armored Vehicle Floor System Design • Crushable Foam Modeling • Ground Vehicle Stability Analysis • Concrete and Glass Fragmentation Modeling • Underwater and Deeply Buried Explosions • Explosively Formed Metal Structures • Glass Foams • Helmet Material Analysis • Polymer Materials • Auxetic Materials.


  • M.S. in Mechanical Engineering | University of Texas at San Antonio | 2008
  • B.E. with a Mechanical Emphasis | John Brown University | 2000 | Summa Cum Laude

Selected Publications

  • Krouse, C., Musgrove, G., Kantrales, G., Barsotti, M., Schoenheit, A., Vandergriff, T. (2019) “Wind Tunnel Testing of Low Solidity Wire Mesh Screens for Large Object Filtration.” Proceedings of ASME Turbo Expo 2019. Phoenix, Arizona.
  • Barsotti, M., Jones, C., Hadjioannou, M., Puryear, J. (2018) “Engineered Material Arresting System and Methods for Forming Same.” United States Patent 2018/0251233 A1.
  • Barsotti, M., Rasico, J., O’Hare, E., Sammarco, E., Gerst, D., Newman, C. (2017) “Accurate Land Mine Modeling Using FEM & SPH with Modified Smoothing Length.” Proceedings of Ground Vehicle Systems Engineering and Technology Symposium. Novi, MI.
  • Bewick, B., Rolater, G., Bui, J., Barsotti, M., Ziemba, A., Sanai, M., Laney, C. (2017) “Fragmentation of Solid Materials Using Shock Tube, Part 1: First Test Series in a Small-Diameter Shock Tube,” Defense Threat Reduction Agency, Report DTRA-TR-17-21. Fort Belvoir, VA, 2017.
  • Barsotti, M., Sammarco, E., Stevens, D. (2016) “Comparison of Strategies for Landmine Modeling in LS-DYNA with Sandy Soil Material Model Development.” Proceedings from 14th International LS-DYNA User’s Conference.
  • Stevens, D., Barsotti, M. (2016) “Modeling of Landmine Loading of Armored Vehicles and Extension to Field Testing Assessment.” Proceedings from Ground Vehicle Systems Engineering and Technology Symposium. Novi, MI.
  • Hadjioannou, M., Stevens, D., Barsotti, M. (2016) “Development and Validation of Bolted Connection Modeling in LS-DYNA for Large Vehicle Models.” Proceedings from 14th International LS-DYNA Users Conference. Detroit, MI.
  • Bewick, B., Barsotti, M., Marchand, K., Sanai, M., Ziemba, A. (2015) “Fragmentation Due to Overloaded Construction Facades.” Proceedings of the 3rd International Conference on Protective Structures. Newcastle, Australia.
  • Puryear, J., Barsotti, M., Stevens, D., Williamson, E., Sammarco, E., Chiarito, V. (2013) “Modeling of Blast-Loaded Steel Cables.” Proceedings of the 15th International Symposium for the Interaction of Munitions with Structures. Potsdam, Germany.
  • Barsotti, M., Puryear, J., Stevens, D., Alberson, R., McMahon, P. (2012) “Modeling Mine Blast with SPH.” Proceedings of the 12th International LS-DYNA Users Conference. Detroit, MI.
  • Barsotti, M. (2011) “Comparison of FEM and SPH for Modeling a Crushable Foam Aircraft Arrestor Bed.” Proceedings of the 11th International LS-DYNA Users Conference. Detroit, MI.
  • Barsotti, M., Puryear, J., Stevens, D. (2009). “ACRP Report 29: Developing Improved Civil Aircraft Arresting Systems.” Transportation Research Board of the National Academies. Washington, DC.
  • Barsotti, M. (2008). “Optimization of a Passive Aircraft arrestor with a Depth-Varying Crushable Material Using a Smoothed Particle Hydrodynamics (SPH) Model.” Thesis at University of Texas, San Antonio, Published by ProQuest.
  • Ammerman, D., Stevens, D., Barsotti, M. (2005) “Numerical Analyses of Locomotive Impacts on a Spent Fuel Truck Cask and Trailer.” Proceedings from ASME 2005 Pressure Vessels and Piping Conference. Denver, CO.

Edward O’Hare, Ph.D.

Dr. Edward O’Hare joined Protection Engineering Consultants as a Sr. Associate Engineer in July of 2015.  Dr. O’Hare received his undergraduate, MS and Ph.D. from the Pennsylvania State University with a dissertation titled “Behavior of Concrete-Filled Tube (CFT) Through-Beam Connections Subjected to Varying Load Rates”.  That research focused on the development of behavioral models and design guidance for CFT-to-CFT energy absorbing through-connections for rigid building frames subjected to varying load rates.  Validated computational models, created in LS-DYNA, were used in a Response Surface Methodology approach to determine appropriate evaluation parameters and to develop design equations.

Eddie spent much of his time at Penn State working in the area of anti-terrorism through his work on Streetscape Vehicular Anti-Ram (SVAR) barrier systems to enhance security interests of the US Department of State world-wide.   This research was supported by full-scale testing and LS-DYNA modeling at Penn State.

Eddie is a US Navy veteran, having served as a Special Security Officer Assistant in the Intelligence Department of the office of the Commander, U.S. Naval Forces, Yokosuka, Japan.  He is experienced with LS-DYNA, MatLab, and SAP2000 numerical analysis tools and will be supporting PEC and our clients on both research and design efforts.  Contact Eddie at 512-380-1988 x313 or

Greg Rolater, P.E.

Greg Rolater joined PEC as an Associate Engineer in March 2014. Greg supports our design projects by providing analysis of structural members for blast resistance and by contributing to design tool development for SBEDS and SBEDS-W.  Greg also provides support for research projects by compiling test data for comparison to theoretical results.  Greg graduated with honors from the University of Texas at San Antonio with a BS in Civil Engineering and MS in Civil/Structural Engineering.


MS in Civil/Structural Engineering | University of Texas at San Antonio | 2022

BS in Civil Engineering | University of Texas at San Antonio | 2013