Mechanics, Structures and Materials

Learning Outcomes

The syllabus of each part of the module is given below. Statics-1 • Fundamental concepts of statics (adding/resolving forces, moments), types of load/support. • Equilibrium of rigid bodies. Free body diagrams. Static determinacy. • Trusses: static determinacy, method of joints and method of sections. • Stress, strain, elastic constants, Hooke's law • Beams: shear force and bending moment diagrams, differential relationships • Engineer's Bending Theory. First and second moments of area. • Beam deflection due to bending, moment-curvature relationship. • Differential equation of the deflection curve. Solution by integration. • Shear stress in beams. Shear formula. Shear stress distribution in practical sections. • Torsion of circular section shafts, polar second moment of area. • Buckling of elastic struts. Concept of instability. Euler formula, effective length. Statics-2 • Stress, strain, elastic constants, thermal strain, Hooke's law (2D/3D) • Stresses in thin-walled cylinders subject to internal pressure. • Two-dimensional analysis of stress. • Stress and strain transformation using Mohr circles. • Principle stresses and strains • Yield criteria and safety factors Dynamics • Particle Dynamics: rectilinear and curvilinear motion; motion of projectiles; pulleys; Newton’s Laws; free body diagrams; equations of motion. • Work and Energy for particles: principle of work and energy; Energy Conservation; Power and efficiency • Principle of linear/angular impulse and momentum for particles • Rigid bodies Dynamics in 2D: kinematics relationships, centre of mass, mass moment of inertia and equations of motion, • Work and energy principle for rigid bodies • Principle of linear/angular impulse and momentum for rigid bodies • The fundamental assumptions of lumped parameter mechanical systems, and concepts of equivalent mass, stiffness and damping • Free vibration analysis of a single degree of freedom mechanical system • Steady state forced vibration analysis of a single degree of freedom system • Definition of the Frequency Response Function (FRF) • Mass, stiffness and damping controlled behaviour. Materials • Materials in Engineering: Metals, ceramics, polymers and composites. • Fundamentals: Atomic structure and interatomic bonding; electrons, atoms and molecules; the Periodic table; bonding and interatomic forces; the structure of crystalline solids; basic structures, unit cells; holes and lattices; imperfections in solids; point, linear, planar and volume defects; diffusion. • Mechanical properties: Stress and strain; elasticity; tensile properties; hardness; strengthening mechanisms; recovery, recrystallisation and grain growth. • Microstructures and their control: Phase diagrams; thermal processing; precipitation hardening • Failure of metals: Failure; fracture, brittle and ductile failure; impact and fracture toughness; fatigue; creep. • Non metallic materials and their properties: Ceramics and glasses; main classes, properties and uses; polymers; basic structures and bonding; polymerisation; cross linking; thermoplastics and thermosets; composites; main classes, properties and uses. • Materials in engineering applications: Case studies.

Learning activities include Lectures and Tutorials as well as self-study with the solution of example problems both in a supervised environment and in their own time. The laboratory sessions include: • Statics beam bending lab • Mechanical testing of materials.