1. Full name: Tran Quoc Quan                            2. Sex: Male

3. Date of birth: 15/05/1990                                4. Place of birth: Ha Tinh

5. Admission decision number: 637/QĐ-CTSV  Dated: 16/09/2013

6. Changes in academic process: No

7. Official thesis title: Nonlinear static stability and dynamic response of FGM double curved shallow shells on elastic foundations

8. Major: Engineering Mechanics                       9. Code: 62520101

10. Supervisors: Professor Nguyen Dinh Duc

11. Summary of the new findings of the thesis:

- Proposing the formula to calculate the change in geometric parameters of stiffeners by temperature as well as the general formula to calculate the force and moment components of eccentrically stiffened FGM structures.

- Based on the classical shell theory and the higher order shear deformation shell theory with the geometrical nonlinearity in von Karman–Donnell sense and the Lekhnitskii, this thesis establishes basic equations to investigate the nonlinear static stability and dynamic response of eccentrically stiffened FGM double curved shallow shells on elastic foundation in which the effects of initial geometric imperfection, temperature dependent properties and the thermal stress in both the shells and the stiffeners are taken into account.

- Establishing governing equations to investigate the nonlinear dynamic response and vibration of imperfect FGM thick double curved shallow shells with piezoelectric actuators on elastic foundations subjected to the combination of electrical, thermal, mechanical and damping loading using the higher order shear deformation shell theory.

- Using analytical approach, Garlerkin method and fourth – order Runge – Kutta method to analyze basic equations to study nonlinear static and dynamic stability of FGM double curved shallow shells subjected to mechanical load, thermal load and the combination of these loads. Specifically, the expressions which show the relationship between loads - amplitude deflection, deflection amplitude – time and frequency – amplitude of linear and nonlinear free and forced vibration are obtained. Using static stability criterion to determine the static critical load and using the Budiansky – Roth criterion to determine the critical dynamic load. The expressions of oscillation frequency are also expressed in analytical formulas.

- Using the iterative algorithm to study the nonlinear stability of eccentrically stiffened FGM double curved shallow shells subjected to thermal load when the material properties depend on temperature.

- This thesis also considers the effects of material and geometrical parameters, eccentrically outside stiffeners, elastic foundations, temperature increment, imperfection and mechanical loads on the nonlinear static stability and dynamic response of FGM double curved shallow shells.

12. Practical applicability, if any:

13. Further research directions, if any:

- Investigations on the nonlinear static and dynamic stability of FGM plates, cylindrical panels and double curved shallow shells reinforced by carbon nanotubes.

Studies on the nonlinear static and dynamic stability of FGM plates, cylindrical panels and double curved shallow shells subjected to special loads (electrical load, blast load, hydrostatic pressure,...).

- Investigations on the nonlinear static and dynamic stability of FGM plates, cylindrical panels and double curved shallow shells with varying thickness.

 - Studies on optimization of the geometrical parameters and material properties of FGM structures.

14. Thesis-related publications:

- Tran Quoc Quan, Nguyen Dinh Duc (2017). “Nonlinear thermal stability of eccentrically stiffened FGM double curved shallow shells”. Thermal Stresses, Vol. 40 (2), pp. 211-236.

- Nguyen Dinh Duc, Tran Quoc Quan, Vu Dinh Luat (2015), “Nonlinear dynamic analysis and vibration of shear deformable piezoelectric FGM double curved shallow shells under damping – thermo – electro – mechanical loads”. Composite Structures, Vol. 125, pp. 29-40.

- Nguyen Dinh Duc, Tran Quoc Quan (2015). “Nonlinear dynamic analysis of imperfect FGM double curved thin shallow shells with temperature-dependent properties on elastic foundation”. Journal of Vibration and Control, Vol. 21 (7), pp. 1340-1362.

- Nguyen Dinh Duc, Tran Quoc Quan (2014). “Transient responses of functionally graded double curved shallow shells with temperature-dependent material properties in thermal environment”. European Journal of Mechanics – A/Solids, Vol. 47, pp. 101-123.

- Nguyen Dinh Duc, Tran Quoc Quan (2013). “Nonlinear postbuckling of imperfect eccentrically stiffened P-FGM double curved thin shallow shells on elastic foundations in thermal environments”. Composite Structures, Vol.106, pp. 590-600.

- Nguyen Dinh Duc, Tran Quoc Quan (2013). “Nonlinear postbuckling of imperfect double curved thin FGM shallow shells on elastic foundations subjected to mechanical loads”. Mechanics of Composite Materials, Vol. 49. N5, pp. 493-506.

- Nguyen Dinh Duc, Tran Quoc Quan (2012). “Nonlinear stability analysis of double curved shallow FGM panel on elastic foundation in thermal environments”. Mechanics of Composite Materials, Vol. 48, N4, pp. 435-448.