1. Full name : Hoang Van Tung
2. Sex: Male
3. Date of birth: 01/05/1981
4. Place of birth: Ninh Binh
5. Admission decision number: 2385/SĐH Dated 29/6/2007. The decision of Director of Vietnam National University, Hanoi.
6. Changes in academic process:
7. Official thesis title: Elastic stability of functionally graded plates and shells
8. Major: Mechanics of Solids
9. Code: 62 44 21 01
10. Supervisors: Ass. Prof. Dr. Sci. Nguyen Dinh Duc, Ass. Prof. Dr. Dao Van Dung
11. Summary of the new findings of the thesis:
1) The thesis uses an analytical approach to investigate nonlinear stability including the buckling and postbuckling behaviors of structures made of functionally graded materials (FGM) in case of temperature independent material properties. In addition, the thesis employs an iterative algorithm to determine buckling loads and postbuckling curves when material properties are temperature dependent.
2) The thesis investigates the nonlinear stability of FGM rectangular plates subjected to mechanical, thermal and combined thermomechanical loads with and without temperature dependence of material properties and taking into account initial geometrical imperfection of the plates.
3) The thesis investigates the nonlinear stability of FGM cylindrical panels subjected to mechanical, thermal and thermomechanical loads by using the classical shell theory and including the initial geometrical imperfection of the panels.
4) The thesis studies the nonlinear stability of FGM circular cylindrical shells by using both the classical shell theory and improved Donnell shell theory.
5) The thesis uses the classical shell theory to investigate axisymmetric nonlinear response of FGM shallow spherical shells taking temperature effects into consideration.
6) The thesis analyzes the effects of material and geometrical properties, boundary conditions, temperature dependence of material properties, imperfection, temperature conditions on the mechanical, thermal and thermomechanical nonlinear stability of FGM plate and shell structures.
12. Practical applicability, if any:
Functionally graded materials are novel composite materials made from mixture of ceramic and metal constituents have capacity of high performance temperature resistance and are widely used in structural components of aircraft, missile, aerospace vehicles and nuclear plants. This thesis, which investigates the buckling and postbuckling behaviors of common engineering structures such as plates, shells and panels made of functionally graded materials, provides scientific predictions for designers of these structures. In addition, obtained results of the thesis may be used as useful reference for calculation, safe and optimal design for nuclear power factories which will be built in Vietnam in near future.
13. Further research directions, if any:
After this, we will study nolinear static stability of FGM structures taking into account the effects of elastic foundations, higher order shear deformation, non-steady temperature conduction and the complexity in the geometry of structures. Furthermore, we will investigate dynamic response including dynamic stability and vibration of FGM plate, shell and panel structures.
14. Thesis-related publications:
Nguyen Dinh Duc, Hoang Van Tung (2008), “Thermal buckling of functionally graded cylindrical panels ”, Proceedings of the International Conference on Computational Solid Mechanics, CSM-2008, Ho Chi Minh City, pp.77-87.
Nguyen Dinh Duc, Hoang Van Tung (2008), “Thermal buckling of imperfect functionally graded cylindrical shells according to Koiter model ”, Proceedings of the International Conference on Computational Solid Mechanics, CSM-2008, Ho Chi Minh City, pp.88-99.
Hoang Van Tung, Nguyen Dinh Duc (2008), “Thermal buckling of imperfect functionally graded cylindrical shells according to Wan-Donnell model”, Vietnam Journal of Mechanics, VAST, Vol. 30, No.3, pp.185-194.
Nguyen Dinh Duc, Hoang Van Tung (2009), “Thermal buckling of laminated plates comprising functionally graded materials”, Tuyển tập công trình Hội nghị Cơ học toàn quốc Kỷ niệm 30 năm Viện Cơ học và 30 năm Tạp chí Cơ học , Hà Nội, pp.30-39.
Hoang Van Tung, Nguyen Dinh Duc (2010), “Thermoelastic stability of thick imperfect functionally graded plates”, Vietnam Journal of Mechanics, VAST, Vol.32, No.1, pp.47-58.
Hoang Van Tung, Nguyen Dinh Duc (2010), “Nonlinear analysis of stability for functionally graded plates under mechanical and thermal loads”, Composite Structures,Vol. 92, pp.1184-1191.
Nguyen Dinh Duc, Hoang Van Tung (2010), “Nonlinear response of pressure-loaded functionally graded cylindrical panels with temperature effects”, Composite Structures,Vol. 92, pp.1664-1672.
Nguyen Dinh Duc, Hoang Van Tung (2010), “Nonlinear analysis of stability for functionally graded cylindrical panels under axial compression”, Computational Materials Science, Vol.49, No.4, pp.313-316.
Nguyen Dinh Duc, Hoang Van Tung (2010), “Mechanical and thermal postbuckling of shear deformable FGM plates with temperature dependent properties”, Journal of Mechanics of Composite Materials, Vol.46, No.5, pp.679-700.
Dao Huy Bich, Hoang Van Tung, “Nonlinear axisymmetric response of functionally graded shallow spherical shells under uniform external pressure including temperature effects”, Submitted to International Journal of Mechanical Sciences.
Dao Huy Bich, Nguyen Xuan Nguyen, Hoang Van Tung, “Postbuckling of functionally graded cylindrical shells based on improved Donnell equations”, Submitted to International Journal of Non-Linear Mechanics.