H. KeoSpringer

Deputy Group Leader, Mesoscale & Hazard Response
Materials Science Division
Email: keo@llnl.gov
Phone: +19254246502


  • Ph.D., Mechanical Engineering, University of California at Davis
  • M.S., Mechanical Engineering, Georgia Institute of Technology - Atlanta, GA
  • B.S., Mechanical Engineering, Cal Poly, San Luis Obispo, CA


Keo has conducted research in energetic materials (EM), material mesoscale effects, and fragmentation modeling at LLNL for over 20 years. He currently leads EM model development and experimental validation efforts for several programs. Under his leadership, his team has developed advanced EM models in LLNL's multi-physics hydrocode ALE3D: HERMES (High Explosive Reaction Mechanical Stimulus) model to assess non-shock ignition, deflagration, and DDT (deflagration-to-detonation transition); Mesoscale modeling to understand structure-property-performance relationships in shock initiation, deconsolidative burning, and fragmentation; Generalized detonation model for weapon assessments over a wide range of explosive types. He has over 40 publications including a book chapter. He is the recipient of the NNSA Defense Programs Award For Outstanding Support of DoD-DOE Joint Munitions Program and Global Security Directorate Award. Keo enjoys working at LLNL where national security intersects S&T.

Selected Publications

  1. (Front Cover) Springer, H.K., Bastea, S., Nichols III, A.L., Tarver, C.M. and Reaugh, J.E., Modeling The Effects of Shock Pressure and Pore Morphology on Hot Spot Mechanisms in HMX. Propellants, Explosives, Pyrotechnics, 43(8), pp.805-817 (2018)
  2. Springer, H.K., Tarver, C.M., Gambino, J.R., White, B.W., Sullivan, K.T. and Gash, A.E., Numerical study on tailoring the shock sensitivity of TATB-based explosives using sub-millimeter features. In AIP Conference Proceedings (Vol. 1979, No. 1, p. 180009). AIP Publishing. (2018).
  3. Reaugh, J.E., White, B.W., Curtis, J.P. and Springer, H.K., A Computer Model to Study the Response of Energetic Materials to a Range of Dynamic Loads. Propellants, Explosives, Pyrotechnics (2018).
  4. Gambino, J.R., Tarver, C.M. and Springer, H.K., Numerical parameter optimizations of the Ignition and Growth model for a HMX plastic bonded explosive. Journal of Applied Physics, 124(19), p.195901 (2018).
  5. Myint, P.C., Gersten, B.T., McClelland, M.A., Nichols III, A.L. and Springer, H.K., Entropy maximization and free energy minimization of multiphase mixtures using particle swarm optimization. In AIP Conference Proceedings (Vol. 1979, No. 1, p. 030006). AIP Publishing (2018).
  6. Springer, H.K., Bastea, S., Gambino, J.R., White, B.W., Sullivan, K.T., Towards Developing Mixture Reactive Flow Models For Additively Manufactured Explosives, Proceedings of the JANNAF 41st PEDCS Joint Subcommittee Meeting (2018). Submitted
  7. Springer, H.K., Bastea, S., Tarver, C.M., Reaugh, J.E., Gresshoff, M., Gee, R.H., Modeling The Effects of Microstructure and Chemical Kinetics on the Short Pulse Shock Initiation Behavior of HMX-Based Explosives, 16th Int. Det. Symp. (2018). Submitted
  8. (Book Chapter) Austin, R.A., Springer, H.K. and Fried, L.E., Grain-scale simulation of shock initiation in composite high explosives. In Energetic Materials (pp. 243-270). Springer, Cham. (2017)
  9. (Cover) Reynolds, J.G., Hsu, P.C., Hust, G.A., Strout, S.A. and Springer, H.K., Hot Spot Formation in Mock Materials in Impact Sensitivity Testing by Drop Hammer. Propellants, Explosives, Pyrotechnics, 42(11), pp.1303-1308 (2017).
  10. Springer, H.K., Sullivan, K.T., Gambino, J.R., White, B.W., Bastea, S., Reeves, R.V., Gash, A.E., “High explosive additive manufacturing modeling: Overview, gaps, and new frontiers”, JANNAF PEDCS Workshop on Additive Manufacturing of Energetic Systems, (2017).
  11. (Cover) Reynolds, J.G., Hsu, P.C., Hust, G.A., Strout, S.A., Hoffman, D.M. and Springer, H.K., Effect of Sandpaper and Grain Size on Non-Shock Initiated Reactions in HMX. Propellants, Explosives, Pyrotechnics, 42(10), pp.1191-1202 (2017).
  12. Springer, H.K., Tarver, C.M. and Bastea, S., Effects of high shock pressures and pore morphology on hot spot mechanisms in HMX. In AIP Conference Proceedings (Vol. 1793, No. 1, p. 080002). (2017).
  13. Gambino, J.R., Springer, H.K., White, B.W., Sullivan, K.T. and Gash, A.E.. Numerical Study of Donor-Acceptor Interface Designs in a Double Cylinder Experiment, Proceedings of the JANNAF 40th PEDCS Joint Subcommittee Meeting (2017).
  14. Hsu, P.C., Zhang, M.X., Pagoria, P., Springer, H.K. and Fried, L., Thermal safety characterization and explosion violence of energetic materials. In AIP Conference Proceedings (Vol. 1793, No. 1, p. 040033). AIP Publishing (2017).
  15. Springer, H.K., Tarver, C.M., White, B.W., Reaugh, J.E., Pfeil, M., Neidert, J.B., “Modeling the shock compaction of debris clouds in delayed detonations”, Proceedings of the JANNAF 30th PSHS Joint Subcommittee Meeting (2017).
  16. McClelland, M.A., Glascoe, E.A., Nichols, A.L., Schofield, S.P. and Springer, H.K.. ALE3D simulation of incompressible flow, heat transfer, and chemical decomposition of Comp B in slow cookoff experiments, 15th Int. Det. Symp. (2015)
  17. Springer, H. K., Vandersall, K. S., Tarver, C. M., Souers, P. C.,  “Investigating shock initiation and detonation in powder HMX with reactive mesoscale simulations”, 15th Int. Det. Symp. (2015)
  18. White, B. W., Springer, H. K., May, C. M., “Investigation of the effects of microstructure and binder properties on impact-induced fragmentation in explosives with meso-scale simulations”, 15th Int. Det. Symp. (2015)
  19. Hsu, P.C., Glascoe, E., Fried, L., Springer, H.K. and Maienschein, J.L., Material Property Characterization of Thermally Damaged HMX-Based Formulations, 15th Int. Det. Symp. (2015)
  20. Willey, T.M., Lauderbach, L., Gagliardi, F., van Buuren, T., Glascoe, E.A., Tringe, J.W., Lee, J.R., Springer, H.K. and Ilavsky, J., "Mesoscale evolution of voids and microstructural changes in HMX-based explosives during heating through the β-δ phase transition." Journal of Applied Physics 118, no. 5 (2015): 055901.
  21. Springer, H.K., Souers, P.C., “Empirical-based development of a generalized detonation model for simulations-based sensitivity studies”, Proceedings of the JANNAF 39th PEDCS Joint Subcommittee Meeting (2015).
  22. White, B.W., Springer, H.K. and Reaugh, J.E., Computational studies of the skid test: Evaluation of the non-shock ignition of LX-10 using HERMES. In Journal of Physics: Conference Series (Vol. 500, No. 19, p. 192021). IOP Publishing (2014)
  23. Springer, H. K., Tarver, C. M., Reaugh, J. E., May, C. M., “Investigating short-pulse shock initiation in HMX-based explosives with reactive meso-scale simulations”, J. Phys.: Conf. Ser. 500 052041 (2014).
  24. Tringe, J. W., Glascoe, E. A., McClelland, M. A., Springer, H. K., et al., “Pre-ignition confinement and deflagration violence in LX-10 and PBX 9501”, J. Appl. Phys. 116, 054903 (2014).
  25. Springer, H.K., Tarver, C.M., Stanfield, J.A., Neidert, J.B., Stowe, D.T., Cogar, J., “Shock-to-detonation transition modeling of the US Army burn-to-violent-reaction rocket motor impact experiments with minimum signature propellants”, Proceedings of the JANNAF 28th PSHS Joint Subcommittee Meeting (2014).
  26. Tringe, J.W., Kercher, J.R., Springer, H.K., Glascoe, E.A., Levie, H.W., Hsu, P., Willey, T.M. and Molitoris, J.D., “Numerical and experimental study of thermal explosions in LX-10 and PBX 9501: Influence of thermal damage on deflagration processes”, J. Appl. Phys. 114, 043504 (2013).
  27. Springer, H. K., Glascoe, E. A., Reaugh, J. E., Kercher, J. R., and Maienschein, J. L., “Mesoscale modeling of deflagration-induced deconsolidation in plastic bonded explosives”, AIP Conf. Proc. 1426, 705 (2012).
  28. Hsu, P.C., Hust, G., May, C.M., Howard, W.M., Chidester, S., Springer, H.K. and Maienschein, J.L., "Study of thermal sensitivity and thermal explosion violence of energetic materials in the LLNL ODTX system." In AIP Conference Proceedings, vol. 1426, no. 1, pp. 559-562. AIP, (2012).
  29. Glascoe, E. A., Springer, H. K., Tringe, J. W., Maienschein, J. L., A comparison of deflagration rates, at elevated pressures and temperatures, with thermal explosion results, AIP Conf. Proc. 1426, (2012).
  30. White, B. W., Springer, H. K., Jordan, J. L., Spowart, J. E., Thadhani, N., “Mesoscale simulations of particle reinforced epoxy-based composite”, AIP Conf. Proc. 1426, 175 (2012).
  31. Nikolaev, S., Phillion, D., Springer, H.K., deVries, W., Jiang, M., Pertica, A., Henderson, J., Horsley, M. and Olivier, S., 2012. Brute Force Modeling of the Kessler Syndrome, Proceedings of the 13th Annual AMOS Conference, (2012)
  32. Springer, H.K., Leininger, L.D., Nichols, A.L., Reaugh, J.E., Stanfield, J.A., Neidert, J.B., “Benchmarking ALE3D modeling with US Army burn-to-violent-reaction sub-scale rocket motor impact experiments”, Proceedings of the JANNAF 27th PSHS Joint Subcommittee Meeting (2012).
  33. Glascoe, E. A., Hsu, P. C., Springer, H. K., et al., “The response of the HMX-based material PBXN-9 to thermal insults: Thermal decomposition kinetics and morphological changes”, Thermochimica Acta, 515:1–2, 58 (2011).
  34. Springer, H. K., Willey, T. M., Friedman, G., Vandersall, K. S., Baer, M. R., “Mesoscale modeling of LX-17 under isentropic compression”, 14th Int. Det. Symp. 1137 (2011).
  35. Lowdermilk, W.H., Rubenchik, A.M. and Springer, H.K.,. Feasibility of High-Power Diode Laser Array Surrogate to Support Development of Predictive Laser Lethality Model, DEPS Conference, (2011)
  36. Tringe, J.W., Glascoe, E.A., Kercher, J.R., Willey, T.M., Springer, H.K., Greenwood, D.W., Molitoris, J.D., Smilowitz, L., Henson, B.F. and Maienschein, J.L., Propagation of Reactions in Thermally-damaged PBX-9501. 14th Int. Det. Symp. 1137 (2011).
  37. Kercher, J.R., Stevens, D.E., Springer, H. K., Georgevich, V.P., 2010, A sub-grid, convective burn model of energetic materials based on the Multiphase framework in ALE3D. Proceedings of the JANNAF, 25th PSHS. (2010)
  38. Springer, H. K., Miller, W. O., Levatin, J. L., Pertica, A. J., and Olivier, S. S., Satellite collision modeling with physics-based hydrocodes: Debris generation predictions of the iridium-cosmos collision event, Proceedings of the 11th Annual AMOS Conference, (2010)
  39. Tringe, J.W., Molitoris, J.D., Smilowitz, L., Kercher, J.R., Springer, H.K., Henson, B.F., Glascoe, E.A., Greenwood, D.W., Garza, R.G., Wong, B.M. and Batteux, J.D., TIME-SEQUENCED X-RAY OBSERVATION OF A THERMAL EXPLOSION. In AIP Conf Proc, 1195, 424-427, (2009).
  40. Goto, D. M., R. Becker, T. J. Orzechowski, H. K. Springer, A. J. Sunwoo, and C. K. Syn. "Investigation of the fracture and fragmentation of explosively driven rings and cylinders." International Journal of Impact Engineering 35, no. 12 (2008): 1547-1556.
  41. Leininger, L. D., Springer, H. K., Mace, J., Mas, E., Modeling the shock initiation of PBX-9501 in ALE3D, Proceedings of the MABS Conference, Oslo, Norway. (2008)