**INTEREST AREAS**

Micro- and nano-mechanics. Multi-scale materials modeling. 3-D printed interpenetrating phase composites. Metamaterials. Traumatic brain injury (TBI). Biomechanics. Mechanics of soft materials. Nanoparticle- and nanotube-reinforced composites. Cellular materials. Textile and ballistic materials. Dynamic behavior of materials. Indentation/contact mechanics. Impact mechanics. Wave propagation. Higher-order (non-local, gradient) continuum theories. Surface elasticity. Damage and fracture mechanics. Modeling of manufacturing processes. Applied mathematics.

**EDUCATION**

- Ph.D. Mechanical Engineering (with a minor in Mathematics), University of Wisconsin-Madison, May 1998
- M.Sc. Engineering Mechanics, University of Wisconsin-Madison, May 1997

**EXPERIENCE**

Dr. Xin-Lin Gao is currently a professor of Mechanical Engineering at Southern Methodist University (SMU). His other experience includes teaching at University of Texas at Dallas for 3 years, at Texas A&M University for 7 years, at Michigan Tech for 4 years, and working at the Air Force Institute of Technology and the Air Force Research Lab for about 2.5 years. He was a visiting professor at University of Paris-East in May-June 2010 and has been a chair professor (visiting) at East China University of Science and Technology (ECUST) in Shanghai. He was elected an ASME Fellow in Dec. 2010.

**RESEARCH**

He has conducted research in a variety of areas in mechanics and materials and is an author/co-author of 123 published/accepted journal papers, three book chapters, and 138 conference publications. The topics covered in his publications include micro- and nanomechanics, multi-scale materials modeling, polymer and metal matrix nanocomposites, higher-order elasticity and plasticity theories, cellular and lattice materials, indentation/contact mechanics, impact mechanics, wave propagation, traumatic brain injury, metamaterials, 3D printed materials, fabric-reinforced composites, textile materials, pressure vessel design, metal cutting simulations, and computational mechanics (finite element method, Green’s function method, variational principles, matrix method for spatial frames, Voronoi tessellation, Monte Carlo method, and molecular dynamics simulations). His work has been funded by NSF, Army, AFOSR, AFRL, DOE, and industries. He has been a reviewer for 114 international journals, 10 publishers and 14 funding organizations and has organized 27 symposia at major technical conferences. He served as the Chair of the ASME/Boeing Structures and Materials Best Paper Award Committee in 2006 and 2007 and is the current Chair of the Structures and Materials Technical Committee of ASME. He serves on the editorial boards of six journals.

**BOOKS AND SPECIAL ISSUES EDITED**

- Li, S. and Gao, X.-L. (2013). Handbook of Micro- and Nanomechanics. Pan Stanford Publishing Co., April 2013. (1206 pages)
- Gao, X.-L. and Li, S. (2012). Special Issue on Mechanics of Heterogeneous Solids and Composite Materials, ASME Journal of Engineering Materials and Technology, Vol. 134, No. 3, July 2012.
- Gao, X.-L. and Zhang, J. (2009). Special Issue on Nonlinear Behaviors of Materials, Mechanics of Advanced Materials and Structures, Vol. 16, No. 7, October 2009.
- Gao, X.-L. (2008). Special Issue on Micro- and Nanomechanics, Mechanics of Advanced Materials and Structures, Vol. 15, No. 8, December 2008.
- Sharma, P. and Gao, X.-L. (2008). Special Issue on Scale Effects in Mechanics, Mathematics and Mechanics of Solids, Vol. 13, No. 3-4, May 2008.

**BOOK CHAPTERS**

- Ding, Y. Y., Akbari, M., Gao, X.-L., Ai, L. and Kovacevic, R. (2018). Use of a robotized laser powder-feed metal additive manufacturing system for fabricating metallic metamaterials. Manufacturing Techniques for Materials: Engineering and Engineered, eds. T. S. Srivatsan, T. S. Sudarshan and K. Manigandan, Chapter 3, pp. 51-66, CRC Press, Boca Raton, FL, March 2018.
- Gao, X.-L. (2013). Strain Gradient Solutions of Eshelby-Type Inclusion Problems. Handbook of Micro- and Nanomechanics, eds. S. Li and X.-L. Gao, Chapter 11, pp. 395434, Pan Stanford Publishing Co., Singapore, April 2013.
- Li, K. and Gao, X.-L. (2011). Micromechanical modeling of three-dimensional open-cell foams. Advances in Soft Matter Mechanics, eds. S. Li and B. Sun, Chapter 8, pp. 213-258, Springer-Verlag and Higher Education Press, Berlin and Beijing, Nov. 2011.

**CITATIONS: 5326, with an h-index of 35 and an i10-index of 81 (AS OF 7/10/2018) Google Scholar**

**RECENT JOURNAL PUBLICATIONS**

- 123. Ai, L. and Gao, X.-L. (2018). An analytical model for star-shaped re-entrant lattice structures with the orthotropic symmetry and negative Poisson’s ratios. Int. J. Mech. Sci. (in press) (available online on June 30, 2018) (DOI: 10.1016/j.ijmecsci.2018.06.027)
- 122. Zhang, G. Y., Gao, X.-L. and Ding, S. R. (2018). Band gaps for wave propagation in 2-D periodic composite structures incorporating microstructure effects. Acta Mech. (in press) (accepted in May 2018).
- 121. Li, Y. Q. and Gao, X.-L. (2018). Modeling of head injuries induced by golf ball impacts. Mech. Adv. Mater. Struct. (published online on March 20, 2018) (DOI: 10.1080/15376494.2018.1446570)
- 120. Gao, X.-L. and Li, Y. Q. (2018). The upper triangular decomposition of the deformation gradient: possible decompositions of the distortion tensor. Acta Mech. 229, 1927-1948.
- 119. Zhang, G. Y., Gao, X.-L., Bishop, J. E. and Fang, H. E. (2018). Band gaps for elastic wave propagation in a periodic composite beam structure incorporating microstructure and surface energy effects. Compos. Struct. 189, 263-272.
- 118. Ai, L. and Gao, X.-L. (2018). Three-dimensional metamaterials with a negative Poisson’s ratio and a non-positive coefficient of thermal expansion. Int. J. Mech. Sci. 135, 101-113.
- 117. Ai, L. and Gao, X.-L. (2017). Micromechanical modeling of 3-D printable interpenetrating phase composites with tailorable effective elastic properties including negative Poisson’s ratio. J. Micromech. Molecular Phys. 2, 1750015-1~21. (DOI: 10.1142/S2424913017500151)
- 116. Li, Y. Q., Gao, X.-L., Horner, S. E. and Zheng, J. Q. (2017). Analytical models for the impact of a solid sphere on a fluid-filled spherical shell incorporating the stress wave propagation effect and their applications to blunt head impacts. Int. J. Mech. Sci. 130, 586-595.
- 115. Zhang, G. Y., Gao, X.-L. and Guo, Z. Y. (2017). A non-classical model for an orthotropic Kirchhoff plate embedded in a viscoelastic medium. Acta Mech. 228, 3811-3825.
- 114. Ai, L. and Gao, X.-L. (2017). Metamaterials with negative Poisson’s ratio and non-positive thermal expansion. Compos. Struct. 162, 70-84.
- 113. Zhang, G. Y., Gao, X.-L. and Tang, S. (2017). A non-classical model for circular Mindlin plates incorporating microstructure and surface energy effects. Procedia IUTAM 21, 48-55.
- 112. Wen, J.-F., Gao, X.-L., Xuan, F.-Z. and Tu, S.-T. (2017). Autofrettage and Shakedown Analyses of an Internally Pressurized Thick-Walled Spherical Shell Based on Two Strain Gradient Plasticity Solutions. Acta Mech. 228, 89-105.
- 111. Gao, X.-L. (2016). Extended Hill’s lemma for non-Cauchy continua based on the simplified strain gradient elasticity theory. J. Micromech. Molecular Phys. 1, 1640004-1~13.
- 110. Gao, X.-L. and Zhang, G. Y. (2016). A non-classical Mindlin plate model incorporating microstructure, surface energy and foundation effects. Proc. Royal Soc. A 472: 20160275-1~25.
- 109. Wen, J.-F., Tu, S.-T., Xuan, F.-Z., Zhang, X.-W. and Gao, X.-L. (2016). Effects of stress level and stress state on creep ductility: evaluation of different models. J. Mater. Sci. Tech. 32, 695-704.
- 108. Ai, L. and Gao, X.-L. (2016). Evaluation of effective elastic properties of 3-D printable interpenetrating phase composites using the meshfree radial point interpolation method. Mech. Adv. Mater. Struct. (published on-line on September 20, 2016) (DOI: 10.1080/15376494.2016.1143990)
- 107. Kulkarni, S., Gao, X.-L., Horner, S. E. and Mortlock, R. F. and Zheng, J. Q. (2016). A transversely isotropic visco-hyperelastic constitutive model for soft tissues. Math. Mech. Solids 21, 747-770.
- 106. Li, X. G., Gao, X.-L. and Kleiven, S. (2016). Behind helmet blunt trauma induced by ballistic impact: a computational model. Int. J. Impact Eng. 91, 56-67.
- 105. Gao, X.-L. and Zhang, G. Y. (2016). A non-classical Kirchhoff plate model incorporating microstructure, surface energy and foundation effects. Continuum Mech. Thermodynamics 28, 195-213.
- 104. Zhang, G. Y., Gao, X.-L. and Wang, J. Z. (2015). A non-classical model for circular Kirchhoff plates incorporating microstructure and surface energy effects. Acta Mech. 226, 4073-4085.
- 103. Li, Y. Q., Li, X. G. and Gao, X.-L. (2015). Modeling of Advanced Combat Helmets under ballistic impact. ASME J. Appl. Mech. 82, 111004–1~9.
- 102. Gao, X.-L. and Su, Y.-Y. (2015). An Analytical study on peeling of an adhesively bonded joint based on a viscoelastic Bernoulli-Euler beam model. Acta Mech. 226, 3059–3067.
- 101. Gao, X.-L., Wen, J.-F., Xuan, F.-Z. and Tu, S.-T. (2015). Autofrettage and shakedown analyses of an internally pressurized thick-walled cylinder based on strain gradient plasticity solutions. ASME J. Appl. Mech. 82(4), 041010-1~12.
- 100. Gao, X.-L. and Zhang, G. Y. (2015). A microstructure- and surface energy-dependent third-order shear deformation beam model. Z. angew. Math. Phys. 66, 1871-1894.
- 99. Gao, X.-L. (2015). A new Timoshenko beam model incorporating microstructure and surface energy effects. Acta Mech. 226, 457–474.
- 98. Zhou, S. S. and Gao, X.-L. (2015). Solutions of the generalized half-plane and half-space Cerruti problems with surface effects. Z. angew. Math. Phys. 66, 1125–1142.
- 97. Zhou, S. S. and Gao, X.-L. (2014). A non-classical model for circular Mindlin plates based on a modified couple stress theory. ASME J. Appl. Mech. 81, 051014-1~8.
- 96. Shaat, M., Mahmoud, F. F., Gao, X.-L. and Faheem, A. F. (2014). Size-dependent bending analysis of Kirchhoff nano-plates based on a modified couple-stress theory including surface effects. Int. J. Mech. Sci. 79, 31-37.
- 95. Ma, H. M. and Gao, X.-L. (2014). A new homogenization method based on a simplified strain gradient elasticity theory. Acta Mech. 225, 1075–1091.
- 94. Gao, X.-L. and Mao, C. L. (2014). Solution of the contact problem of a rigid conical frustum indenting a transversely isotropic elastic half-space. ASME J. Appl. Mech. 81, 041007-1~12.
- 93. Su, Y.-Y. and Gao, X.-L. (2014). Analytical model for adhesively bonded composite panel-flange joints based on the Timoshenko beam theory. Compos. Struct. 107, 112-118.
- 92. Wen, J.-F., Tu, S.-T., Gao, X.-L. and Reddy, J. N. (2014). New model for creep damage analysis and its application to creep crack growth simulations. Mater. Sci. Tech. 30, 32-37.
- 91. Kulkarni, S. and Gao, X.-L. (2014). A predictive study of effective properties and progressive failure of tri-axially woven SiCf-SiC composites. Int. J. Automotive Compos. 1, 39-51.
- 90. Liu, M. Q. and Gao, X.-L. (2014). Solution of the Eshelby-type anti-plane strain polygonal inclusion problem based on a simplified strain gradient elasticity theory. Acta Mech. 225, 809–823.
- 89. Gao, X.-L. and Mahmoud, F. F. (2014). A new Bernoulli-Euler beam model incorporating microstructure and surface energy effects. Z. angew. Math. Phys. 65, 393–404.
- 88. Ma, H. M. and Gao, X.-L. (2013). Strain gradient solution for a finite-domain Eshelby-type anti-plane strain inclusion problem. Int. J. Solids Struct. 50, 3793-3804.
- 87. Gao, X.-L., Huang, J. X. and Reddy, J. N. (2013). A non-classical third-order shear deformation plate model based on a modified couple stress theory. Acta Mech. 224, 2699–2718.
- 86. Kulkarni, S., Gao, X.-L., Horner, S. E. , Zheng, J. Q. and David, N. V. (2013). Ballistic helmets – their design, materials, and performance against traumatic brain injury. Compos. Struct. 101, 313-331.
- 85. Wen, J.-F., Tu, S.-T., Gao, X.-L. and Reddy, J. N. (2013). Simulations of creep crack growth in 316 stainless steel using a new creep-damage model. Eng. Fract. Mech. 98, 169-184.
- 84. Gao, X.-L. and Zhou, S. S. (2013). Strain gradient solutions of half-space and half-plane contact problems. Z. angew. Math. Phys. 64, 1363-1386.
- 83. Liu, M. Q. and Gao, X.-L. (2013). Strain gradient solution for the Eshelby-type polygonal inclusion problem. Int. J. Solids Struct. 50, 328-338.
- 82. Zhou, S. S. and Gao, X.-L. (2013). Solutions of half-space and half-plane contact problems based on surface elasticity. Z. angew. Math. Phys. 64, 145-166.
- 81. David, N. V., Gao, X.-L. and Zheng, J. Q. (2013). Creep of a Twaron®/natural rubber composite. Mech. Adv. Mater. Struct. 20, 464-477.
- 80. Su, Y.-Y. and Gao, X.-L. (2013). An analytical study on peeling of an adhesively bonded joint based on the Timoshenko beam theory. Mech. Adv. Mater. Struct. 20, 454-463.
- 79. Gao, X.-L. and Ma, H. M. (2012). Strain gradient solution for the Eshelby-type anti-plane strain inclusion problem. Acta Mech. 223, 1067-1080.
- 78. Zhou, S. S., Gao, X.-L. and Griffith, G. W. (2012). Analysis and structural optimization of a three-layer composite cladding tube under thermo-mechanical loads. ASME J. Eng. Mater. Tech. 134, 031001-1~12.
- 77. Gogineni, S., Gao, X.-L., David, N. V. and Zheng, J. Q. (2012). Ballistic impact of Twaron CT709® plain weave fabrics. Mech. Adv. Mater. Struct. 19, 441-452.
- 76. Gao, X.-L. and Liu, M. Q. (2012). Strain gradient solution for the Eshelby-type polyhedral inclusion problem. J. Mech. Phys. Solids 60, 261-276.
- 75. Wang, X. and Gao, X.-L. (2011). On the uniform stress state inside an inclusion of arbitrary shape in a three-phase composite. Z. angew. Math. Phys. 62, 1101-1116.
- 74. Ma, H. M., Gao, X.-L. and Reddy, J. N. (2011). A non-classical Mindlin plate model based on a modified couple stress theory. Acta Mech. 220, 217-235.
- 73. Zhou, S. S., Gao, X.-L. and He, Q.-C. (2011). A unified treatment of axisymmetric adhesive contact problems using the harmonic potential function method. J. Mech. Phys. Solids 59, 145-159.
- 72. Ma, H. M. and Gao, X.-L. (2011). Strain gradient solution for the finite-domain Eshelby-type plane strain inclusion problem and Eshelby’s tensor for a cylindrical inclusion in a finite elastic matrix. Int. J. Solids Struct. 48, 44-55.
- 71. David, N. V., Gao, X.-L. and Zheng, J. Q. (2011). Stress relaxation of a Twaron®/ natural rubber composite. ASME J. Eng. Mater. Technol. 133, 011001-1~9.
- 70. Sun, L.-H., Ounaies, Z., Gao, X.-L., Whalen, C. A. and Yang, Z.-G. (2011). Preparation, characterization and modeling of carbon nanofiber reinforced epoxy nanocomposites. J. Nanomaterials 2011, 307589-1~8.
- 69. Gao, X.-L. and Ma, H. M. (2010). Strain gradient solution for Eshelby’s ellipsoidal inclusion problem. Proc. Royal Soc. A 466, 2425-2446.
- 68. Gao, X.-L. and Ma, H. M. (2010). Solution of Eshelby’s inclusion problem with a bounded domain and Eshelby’s tensor for a spherical inclusion in a finite spherical matrix based on a simplified strain gradient elasticity theory. J. Mech. Phys. Solids 58, 779-797.
- 67. Ma, H. M., Gao, X.-L. and Benson Tolle, T. (2010). Monte Carlo modeling of the fiber curliness effect on percolation of conductive composites. Appl. Phys. Lett. 96, 061910-1~3.
- 66. David, N. V., Gao, X.-L. and Zheng, J. Q. (2010). Constitutive behavior of a Twaron®/natural rubber composite. Mech. Adv. Mater. Struct. 17, 246-259.
- 65. Ma, H. M. and Gao, X.-L. (2010). Eshelby’s tensors for plane strain and cylindrical inclusions based on a simplified strain gradient elasticity theory. Acta Mech. 211, 115-129
- 64. Ma, H. M., Gao, X.-L. and Reddy, J. N. (2010). A non-classical Reddy-Levinson beam model based on a modified couple stress theory. Int. J. Multiscale Comput. Eng. 8, 167-180.
- 63. David, N. V., Gao, X.-L. and Zheng, J. Q. (2009). Ballistic resistant body armor: contemporary and prospective materials and related protection mechanisms. Appl. Mech. Rev. 62, 050802-1~20.
- 62. David, N. V., Gao, X.-L. and Zheng, J. Q. (2009). Modeling of viscoelastic behavior of ballistic fabrics at low and high strain rates. Int. J. Multiscale Comput. Eng. 7, 295-308.
- 61. Gao, X.-L. and Ma, H. M. (2009). Green’s function and Eshelby’s tensor based on a simplified strain gradient elasticity theory. Acta Mech. 207, 163-181.
- 60. Li, K., Gao, X.-L., Fielding, J. C. and Benson Tolle, T. (2009). Modeling of electrical conductivity of nickel nanostrand filled polymer matrix composites. J. Comput. Theoretical Nanoscience 6, 494-504.
- 59. Gao, X.-L., Park, S. K. and Ma, H. M. (2009). Analytical solution for a pressurized thick-walled spherical shell based on a simplified strain gradient elasticity theory. Math. Mech. Solids 14, 747-758.
- 58. Gu, H., Gao, X.-L. and Li, X. (2009). Molecular dynamics study on mechanical properties and interfacial morphology of aluminum matrix nanocomposites reinforced by Beta-silicon carbide nano-particles. J. Comput. Theoretical Nanoscience 6, 61-72.
- 57. Ma, H. M., Gao, X.-L. and Reddy, J. N. (2008). A microstructure-dependent Timoshenko beam model based on a modified couple stress theory. J. Mech. Phys. Solids 56, 3379-3391. (The most cited article published in Elsevier’s Journal of the Mechanics and Physics of Solids since 2008 as of 12/31/2013)
- 56. Park, S. K. and Gao, X.-L. (2008). Micromechanical modeling of honeycomb structures based on a modified couple stress theory. Mech. Adv. Mater. Struct. 15, 574-593.
- 55. Park, S. K. and Gao, X.-L. (2008). Variational formulation of a modified couple stress theory and its application to a simple shear problem. Z. angew. Math. Phys. 59, 904-917.
- 54. Ma, H. M. and Gao, X.-L. (2008). A three-dimensional Monte Carlo model for electrically conductive polymer matrix composites filled with curved fibers. Polymer 49, 4230-4238.
- 53. Gao, X.-L. (2008). Analytical solution for the stress field around a hard spherical particle in a metal matrix composite incorporating size and finite volume effects. Math. Mech. Solids 13, 357-372.
- 52. Gao, X.-L. and Park, S. K. (2007). Variational formulation of a simplified strain gradient elasticity theory and its application to a pressurized thick-walled cylinder problem. Int. J. Solids Struct. 44, 7486-7499.
- 51. Ghosh, D., Subhash, G., Sudarshan, T. S., Radhakrishnan, R. and Gao, X.-L. (2007). Dynamic indentation response of fine-grained boron carbide. J. Am. Ceram. Soc. 90, 1850-1857.
- 50. Li, K., Gao, X.-L. and Wang, J. (2007). Dynamic crushing behavior of honeycomb structures with irregular cell shapes and non-uniform cell wall thickness. Int. J. Solids Struct. 44, 5003-5026.
- 49. Gao, X.-L. (2007). Strain gradient plasticity solution for an internally pressurized thick-walled cylinder of an elastic linear-hardening material. Z. angew. Math. Phys. 58, 161-173.
- 48. Park, S. K. and Gao, X.-L. (2006). Bernoulli-Euler beam model based on a modified couple stress theory. J. Micromech. Microeng. 16, 2355-2359.
- 47. Gao, X.-L. (2006). An expanding cavity model incorporating strain-hardening and indentation size effects. Int. J. Solids Struct. 43, 6615-6629.
- 46. Li, K., Gao, X.-L. and Roy, A.K. (2006). Micromechanical modeling of viscoelastic properties of carbon nanotube-reinforced polymer composites. Mech. Adv. Mater. Struct. 13, 317-328.
- 45. Gao, X.-L. (2006). A new expanding cavity model for indentation hardness including strain-hardening and indentation size effects. J. Mater. Research 21, 1317-1326.
- 44. Gao, X.-L., Jing, X.N. and Subhash, G. (2006). Two new expanding cavity models for indentation deformations of elastic strain-hardening materials. Int. J. Solids Struct. 43, 2193-2208.
- 43. Li, K., Gao, X.-L. and Subhash, G. (2006). Effects of cell shape and strut cross-sectional area variations on the elastic properties of three-dimensional open-cell foams. J. Mech. Phys. Solids 54, 783-806.
- 42. Gao, X.-L. (2006). Strain gradient plasticity solution for an internally pressurized thick-walled spherical shell of an elastic linear-hardening material. Mech. Adv. Mater. Struct. 13, 43-49.
- 41. Subhash, G., Liu, Q. and Gao, X.-L. (2006). Quasi-static and high strain-rate uniaxial compressive response of polymeric structural foams. Int. J. Impact Engr. 32, 1113-1126.
- 40. Jing, X.N., Zhao, J.H., Subhash, G. and Gao, X.-L. (2005). Anisotropic grain growth with pore drag under applied loads. Mater. Sci. Eng. A 412, 271-278.
- 39. Liu, Q., Subhash, G. and Gao, X.-L. (2005). A parametric study on crushability of open-cell structural polymeric foams. J. Porous Mater. 12, 233-248.
- 38. Li, K., Gao, X.-L. and Roy, A.K. (2005). Micromechanical modeling of three-dimensional open-cell foams using the matrix method for spatial frames. Composites: Part B 36, 249-262.
- 37. Li, K., Gao, X.-L. and Subhash, G. (2005). Effects of cell shape and cell wall thickness variations on the elastic properties of two-dimensional cellular solids. Int. J. Solids Struct. 42, 1777-1795. (One of the 50 most cited articles published in IJSS between 2004 and 2008 as of 10/25/2009)
- 36. Gao, X.-L. and Li, K. (2005). A shear-lag model for carbon nanotube-reinforced polymer composites. Int. J. Solids Struct. 42, 1649-1667. (One of the 50 most cited articles published in IJSS between 2004 and 2008 as of 10/25/2009)(No. 15 of the SciVerse ScienceDirect Top 25 for 2009-2010 Academic Year – IJSS; No. 18 of the SciVerse ScienceDirect Top 25 for Jan.-Dec. 2011 – IJSS)
- 35. Gao, X.-L. (2004). On the complex variable displacement method in plane isotropic elasticity. Mech. Res. Comm. 31, 169-173.
- 34. Gao, X.-L. and Li, K. (2003). Finite deformation continuum model for single-walled carbon nanotubes. Int. J. Solids Struct. 40, 7329-7337.

(Updated on 7/10/2018)