Major Morris S. & DeEtte A. Anderson Memorial LSU Alumni Professor of Mechanical Engineering
Holder of the John W. Rhea Jr. Professorship in Engineering
3250B Patrick F. Taylor Hall
Department of Mechanical & Industrial Engineering
Louisiana State University
Baton Rouge, LA 70803
Google Scholar Profile - Li (click me)
- Ph.D., Civil Engineering, Southeast University, China, 1997
- M.S., Civil Engineering, Beijing University of Technology, China, 1988
- B.S., Civil Engineering, Hebei University of Technology, China, 1985
My research goal is to advance knowledge and develop enabling technology in stimuli-responsive polymers and polymer composites related to engineering structures and devices.
My research group has been focused on fiber reinforced polymer composite materials and composite structures, and on understanding their constitutive behavior and damage/fracture/healing per engineering mechanics principle. Especially, my research encompasses (1) analytical modeling and experimental studies on impact and crashworthiness of composite structures; (2) analytical modeling and experimental testing of fracture and cohesive law of adhesively bonded composite structures; (3) composite piping system including smart composite piping systems for energy storage and transport; (4) construction materials including solid waste recycling, sealant, and cement-asphalt emulsion composite; (5) fiber reinforced polymer composites; (6) manufacturing, testing, and modeling of advanced grid stiffened composite structures and sandwich structures; (7) modeling, testing, and manufacturing (including additive manufacturing) of shape memory polymer (SMP) based biomimetic self-healing composites, including self-healing ceramic; (8) polymeric artificial muscles; (9) polymeric matrix nanocomposites; (10) repair/rehabilitation/reinforcement/replacement/new construction of damaged composite structures, including reinforced concrete structures; (11) stress and failure analysis of particulate-filled composites, including cement concrete and asphalt concrete; (12) thermomechanical constitutive modeling and experimental testing of SMP composites, including one-way, two-way, and multi-shape SMP composites.
One of my studies focuses on self-healing polymer and polymer composite based on a biomimetic two-step close-then-heal (CTH) strategy for repeatedly healing wide-opened cracks, including self-healing of polymer composites under service conditions such as subjected to tensile stress and/or at low temperature. Step 1: narrowing or closing the macroscopic crack through constrained shape recovery of shape memory polymers (SMPs) (either through constrained expansion of compression programmed SMP matrix, or through constrained shrinkage of dispersed and tension programmed SMP fibers or homochiral polymeric artificial muscles); Step 2: healing the narrowed crack either extrinsically through melting, diffusion, randomization, and cooling of thermoplastic healing agent, or intrinsically through self-healing polymer matrix such as thermosets with dynamic covalent bond exchange chemistry, ionomers, two-way SMPs, etc.
Another example of my research focuses on constitutive modeling of stimuli responsive polymers such as one-way SMPs, two-way SMPs, and polymeric artificial muscles. Specifically, my research has used thermodynamics, statistical mechanics, and solid mechanics principles, and has modeled the constitutive behavior of the various stimuli-responsive polymers and polymer composites, including amorphous SMPs, semi-crystalline SMPs, SMP fibers, SMP based artificial muscles, SMP based syntactic foams, as well as programming at glassy temperatures.
Over the years, my group has also conducted research on adhesively bonded composite joints, including stress analysis, cohesive law models under Mode I, Mode II, and mixed Mode I&II fracture modes, and has studied the effect of adhesive thickness on the energy release rate, cohesive strength, and traction-separation laws. My interest is also in modeling of fracture of structures created through additive manufacturing such as printing of metallic powders by selective laser melting.
L. Lu, J. Fan, and G. Li. Intrinsic Healable and Recyclable Thermoset Epoxy Based on Shape Memory Effect and Transesterification Reaction. Polymer, Vol. 105, pp. 10–18, (October, 2016).
Q. Yang and G. Li. A Top-down Multi-scale Modeling for Actuation Response of Polymeric Artificial Muscles. Journal of the Mechanics and Physics of Solids, Vol. 92, pp. 237–259, (July, 2016).
L. Lu and G. Li. One-way multi-shape memory effect and tunable two-way shape memory effect of ionomer poly(ethylene-co-methacrylic acid). ACS Applied Materials & Interface, Vol. 8, No. 23, pp 14812–14823, (June, 2016).
P. Zhang and G. Li. Recent Advances in Healing-on-Demand Polymers and Polymer Composites. Progress in Polymer Science, Vol. 57, pp. 32-63, (June 2016).
Q. Yang and G. Li. Temperature and rate dependent thermomechanical modeling of shape memory polymers with physics based phase evolution law. International Journal of Plasticity, Vol. 80, pp. 168-186, (May 2016).
S. Sharafi and G. Li. A Multiscale Approach for Modeling Actuation Response of Polymeric Artificial Muscle. Soft Matter, Vol. 11, No. 19, pp. 3833 – 3843, (May 2015).
P. Zhang and G. Li. Healing-on-demand Composites Based on Polymer Artificial Muscle. Polymer, Vol. 64, pp. 29-38, (May, 2015).
A. Shojaei, S. Sharafi, and G. Li. A Multiscale Theory of Self-Crack-Healing with Solid Healing Agent Assisted by Shape Memory Effect. Mechanics of Materials, Vol. 81, 25-40, (February, 2015).
G. Li. Self-Healing Composites: Shape Memory Polymer Based Structures. ISBN-10: 1118452429 and ISBN-13: 978-1118452424, John Wiley & Sons, Inc., West Sussex, UK, (November, 2014).
A. Shojaei and G. Li. Thermomechanical Constitutive Modeling of Shape Memory Polymer Including Continuum Functional and Mechanical Damage Effects. Proceedings of the Royal Society A-Mathematical Physical and Engineering Sciences, Vol. 470, No. 2170, paper number 20140199, (October, 2014).
G. Li and P. Zhang. A Self-healing Particulate Composite Reinforced with Strain Hardened Short Shape Memory Polymer Fibers. Polymer, Vol. 54, No. 18, pp. 5075-5086, (August, 2013).
H. Meng and G. Li. A Review of Stimuli-responsive Shape Memory Polymer Composites. Polymer, Vol. 54, No. 9, pp. 2199-2221 (April, 2013).
A. Shojaei and G. Li. Viscoplasticity Analysis of Semicrystalline Polymers: A Multiscale Approach within Micromechanics Framework. International Journal of Plasticity, Vol. 42, pp. 31-49, (March 2013).
G. Li, O. Ajisafe, H. Meng. Effect of Strain Hardening of Shape Memory Polymer Fibers on Healing Efficiency of Thermosetting Polymer Composites. Polymer, Vol. 54, No. 2, pp. 920-928, (January, 2013).
G. Li, H. Meng, and J. Hu. Healable Thermoset Polymer Composite Embedded with Stimuli-responsive Fibers. Journal of the Royal Society Interface, Vol. 9, No. 77, pp. 3279-3287, (December, 2012).
G. Li and A. Shojaei. A Viscoplastic Theory of Shape Memory Polymer Fibers with Application to Self-Healing Materials. Proceedings of the Royal Society A-Mathematical Physical and Engineering Sciences, Vol. 468, No. 2144, pp. 2319-2346, (August, 2012).
G. Ji, Z. Ouyang, and G. Li. On the Interfacial Constitutive Laws of Mixed Mode Fracture with Various Adhesive Thicknesses. Mechanics of Materials, Vol. 47, pp. 24-32, (April, 2012).
W. Xu and G. Li. Thermoviscoplastic Modeling and Testing of Shape Memory Polymer Based Self-healing Syntactic Foam Programmed at Glassy Temperature. ASME Journal of Applied Mechanics, Vol. 78, No. 6, paper number 061017, (November, 2011).
G. Li and T. Xu. Thermomechanical characterization of shape memory polymer based self-healing syntactic foam sealant for expansion joint. ASCE Journal of Transportation Engineering, Vol. 137, No. 11, pp. 805-814, (November, 2011).
G. Li and W. Xu. Thermomechanical Behavior of Thermoset Shape Memory Polymer Programmed by Cold-Compression: Testing and Constitutive Modeling. Journal of the Mechanics and Physics of Solids, Vol. 59, No. 6, pp. 1231–1250, (June, 2011).
J. Nji and G. Li. A Biomimic Shape Memory Polymer Based Self-healing Particulate Composite. Polymer, Vol. 51, No. 25, pp. 6021-6029, (November, 2010).
G. Ji, Z. Ouyang, G. Li, S.I. Ibekwe, and S.S. Pang. Effects of Adhesive Thickness on Global & Local Mode-I Interfacial Fracture of Bonded Joints. International Journal of Solids and Structures, Vol. 47, No. 18-19, pp. 2445-2458, (September, 2010).
G. Li and N. Uppu. Shape Memory Polymer Based Self-Healing Syntactic Foam: 3-D Confined Thermomechanical Characterization. Composites Science and Technology, Vol. 70, No. 9, pp. 1419-1427, (September, 2010).
M. John and G. Li. Self-Healing of Sandwich Structures with Grid Stiffened Shape Memory Polymer Syntactic Foam Core. Smart Materials and Structures, Vol. 19, No. 7, paper number 075013, (July, 2010).
W. Xu and G. Li. Constitutive Modeling of Shape Memory Polymer Based Self-healing Syntactic Foam. International Journal of Solids and Structures, Vol. 47, No. 9, pp.1306-1316, (May, 2010).
J. Nji and G. Li. A Self-Healing 3D Woven Fabric Reinforced Shape Memory Polymer Composite for Impact Mitigation. Smart Materials and Structures, Vol. 19, No. 3, paper number 035007, (March, 2010).
G. Li and D. Nettles. Thermomechanical Characterization of a Shape Memory Polymer Based Self-Repairing Syntactic Foam. Polymer, Vol. 51, No. 3, pp. 755-762, (February, 2010).
G. Li and M. John. A Self-Healing Smart Syntactic Foam under Multiple Impacts. Composites Science and Technology, Vol. 68, No. (15-16), pp. 3337-3343, (December, 2008).
G. Li and V.D. Muthyala. Impact Characterization of Sandwich Structures with an Integrated Orthogrid Stiffened Syntactic Foam Core. Composites Science and Technology, Vol. 68, No. 9, pp. 2078-2084, (July, 2008).
G. Li and D. Maricherla. Advanced Grid Stiffened FRP Tube Encased Concrete Cylinders. Journal of Composite Materials, Vol. 41, No. 15, pp. 1803-1824, (August, 2007).
G. Li. Experimental Study of FRP Confined Concrete Cylinders. Engineering Structures, Vol. 28, No. 7, pp. 1001-1008, (June, 2006).
G. Li, S. Torres, W. Alaywan, and C. Abadie. Experimental Study of FRP Tube-Encased Concrete Columns. Journal of Composite Materials, Vol. 39, No. 13, pp. 1131-1145, (July, 2005).
G. Li, M. A. Stubbelfield, G. Garrick, J. Eggers, C. Abadie, and B. Huang. Development of Waste Tire Modified Concrete. Cement and Concrete Research, Vol. 34, No. 12, pp. 2283-2289, (December, 2004).
G. Li, D. Mukai, S.S. Pang, J.E. Helms, S.I. Ibekwe, and W. Alaywan. Stiffness Degradation of FRP Strengthened RC Beams Subjected to Hygrothermal and Aging Attacks. Journal of Composite Materials, Vol. 36, No. 7, pp. 795-812, (April, 2002).
G. Li, Y. Li, J.B. Metcalf, and S.S. Pang. Elastic Modulus Prediction of Asphalt Concrete. ASCE Journal of Materials in Civil Engineering, Vol. 11, No. 3, pp. 236 - 241, (August, 1999).
G. Li, Y. Zhao, and S.S. Pang. Four-Phase Sphere Modeling of Effective Bulk Modulus of Concrete. Cement and Concrete Research, Vol. 29, No. 6, pp. 839 - 845, (June, 1999).
G. Li, Y. Zhao, S.S. Pang, and W. Huang. Experimental Study of Cement-Asphalt Emulsion Composite. Cement and Concrete Research, Vol. 28, No.5, pp. 635 - 641, (May, 1998).
“RII Track-1: Louisiana Consortium for Innovation in Manufacturing and Materials (CIMM),” Funded by NSF, (PI: M. Khonsari, Co-PIs: WJ Meng, P. Sprunger, B. Ramachandran, G. Li,), $20,000,000, 08/01/2015-07/30/2020.
“Damage Healing of Polymer Composite Structures under Service Conditions,” Funded by NASA-BoR/EPSCoR, (Science PI: I. Warner, Co-Is: G. Li, S. Ibekwe, and P. Mensah), $1,390,000, 08/17/16-08/16/19.
“A Spider Silk Like Fiber for Vibration Damping,” Funded by NSF, (Single PI: G. Li), $366,992, 09/01/2013-08/31/2017.
“Bio-mimetic Self-healing Composite Sandwich for Impact Tolerant NextGen Aerospace Structures,” Funded by NASA-BoR/EPSCoR, (Science PI: G. Li, Co-Is: S.S. Pang, D. Zhang, Z. Ouyang, and S. Ibekwe), 07/08/2011 – 07/07/2015, $1,410,000.
“Next Generation Composites CREST Center: NextGenC3,” Funded by NSF, (PI: E. Woldesenbet, Co-PIs: G. Li, E. Walker, and K. Crosby), 09/01/2009-08/31/2016, $5,100,000.
“A Self-Healing Smart Syntactic Foam,” Funded by NSF, (Single PI: G. Li), 08/01/2009-07/31/2013, $280,000.
“Smart Adhesively Bonded High-Performance Joints for Composite Structures,” funded by NASA-BoR/EPSCoR, (Science PI: G. Li, Co-PIs: S.S. Pang, M.A. Wahab, M.A. Stubblefield, and K. Lian), 10/01/07-09/30/11, $1,434,000.
“Testing and Modeling of Blast Response of Functionally Graded Composite Armor,” funded by the DoD, (PI: G. Li, Co-PI: E. Woldesenbet, S.I. Ibekwe, Additional Investigators: J.Q. Cheng and Z. Lei), 10/01/06-09/30/10, $300,000.
“Towards Miniaturization of the Naval Nuclear Propulsion Reactors: Novel Processing Routes of Fabricating Microstructures on Pressurized Water Reactors,” funded by the DoE, (Project PI: S.I. Ibekwe, Co-PIs: G. Li, K. Lian, and S.S. Pang), 10/01/2005-09/30/2009, $1,500,000.
“Composite Columns and Poles for Infrastructure and Homeland Security Applications,” funded by BoR and EDO Fiber Science, (PI: G. Li, Co-PI: Y. Ram, Additional investigators: M.A. Wahab, and E. Woldesenbet), 06/01/04-06/30/08, $195,000.