Roles

Dr. Mohamed Ali Hjaji is a faculty member in the Department of Mechanical and Industrial Engineering, specializing in Applied Mechanics at the College of Engineering. He joined the Mechanical Engineering Department as an Assistant Lecturer on July 1, 2000. He has taught various courses in Applied Mechanics, including Statics (GE121), Strength of Materials (ME204), Stress Analysis I and II (ME205, ME303), Mechanical Vibrations 1 and 2 (ME325, ME425), Mechanics of Machines 1 and 2 (ME306, ME406), and Mechanics of composite materials (ME524).

Dr. Al-Hajjaji has supervised numerous undergraduate thesis projects in various fields, such as:

1. Bending vibrations of Euler-Bernoulli beams and Timoshenko beams subjected to various harmonic bending loads, including the development of a finite element to find static and dynamic responses and natural frequencies and modes of these beams.
2. Dynamic torsional analysis of non-rotating columns.
3. Structural analysis of a steel frame for a two-story smart vertical parking.
4. Thermal buckling of composite material columns.
5. Static analysis of composite laminated beams under various bending loads.
6. Dynamic analysis of antisymmetric composite laminated beams subjected to various harmonic excitations.
7. Laminated plates under hygrothermal loads.
8. Torsional vibration analysis of constrained structural members.
9. Failure analysis of composite laminates.
10. Vibrational analysis and mathematical modeling of a quarter vehicle suspension system.

Currently, Dr. Mohamed Al-Hajjaji is an Associate Professor at the University of Tripoli and has numerous scientific publications in his field of expertise. Some examples include:

1. Study of static and dynamic analysis of structural members with thin-walled closed and open cross-sections under various static and dynamic forces. These studies investigate the coupled longitudinal-bending and torsional deformations, their effects on static and dynamic responses, and the extraction of natural frequencies and modes.
2. Symmetric Sandwich beams: Dynamic axial-transverse coupled analysis of symmetric sandwich beams under harmonic bending forces. The research involved deriving governing equations of motion for sandwich beams under harmonic bending forces and obtaining closed-form solutions for axial-transverse steady-state conditions, which were used as exact shape functions in finite element analysis for obtaining quasi-static and dynamic responses.
3. Coupled dynamic analysis of torsion and twisting in thin-walled open-section symmetric beams subjected to torsional and warping moments. This research derived exact solutions for static responses and developed a finite element to study coupled torsional and twisting responses.
4. Composite laminated materials:  The published papers studying the dynamic response of symmetric laminated composite beams under various harmonic forces.
5. Finite element Formulation: Several papers published on static and dynamic analysis of various structural members, including columns and beams with isotropic and orthotropic composite materials, as well as symmetric sandwich beams. These studies derived exact closed-form solutions for static and dynamic analyses for different structural members. The closed-form solutions were developed for use as exact shape functions in finite element models of beams and other structural members. 

Careers

Prior to joining the University of Tripoli, Al-Hajji worked for many years at the Industrial Research Center. He joined the University of Tripoli in the Applied Mechanics Division of the Mechanical and Industrial Engineering Department.

Research Interests

Dr. Hjaji is classified as research active, and he has published in a range of peer reviewed, internationally recognised, journals. These include the Journal of Mechanical Engieering and others. 

External Activities

Participation in the referee of some scientific papers