prof. Ing. Jindřich Petruška, CSc.

Institute of Solid Mechanics, Mechatronics and Biomechanics

Students will be able to analyze common problems of strength and elasticity, to choose an appropriate method of evaluation of stress, deformation and safety via either analytical solution or preparation of input data for a numerical solution or proposal of an experimental method. They will be able to distinguish and assess basic types of failures of engineering structures.

Mathematics: linear algebra, matrix notation, functions of one and more variables, differential and integral calculus, ordinary and partial differential equations. Ability of application of mathematical software (Maple) is required as well.
Basic knowledge of statics (especially equations of statical equilibrium and free body diagrams) and mechanics of materials (stress and strain tensors, elasticity theory of bars, failure criteria for ductile and brittle materials).

The course is taught through lectures explaining the basic principles and theory of the discipline. Exercises are focused on practical topics presented in lectures.

The course-unit credit is granted under conditions of active participation in seminars and passing seminar tests of basic knowledge (at least 10 ECTS points out of 20 must be gained). The points gained in seminar tests are included in the final evaluation of the course.
Final exam: Written part of the examination plays a decisive role, where the maximum of 80 ECTS points can be reached. It consists of a written theoretical test evaluated with max. 30 points and solution of two computational problems (50 pts max.). The problems concern typical profile areas of the subject. The lecturer will specify exact demands like types problems during the semester preceding the examination.
Final evaluation of the course is obtained as the sum of ECTS points gained in seminars and at the examination. To pass the course, at least 50 points must be reached.

English

The aim of the course is to enlarge the students' knowledge on possibilities of assessment of safety of engineering structures. Students should get broader knowledge on failure criteria, especially under conditions of cyclic loading and existence of cracks in the body. They should also become capable to solve stresses and deformations in various model bodies analytically, and obtain basic information on possibilities of stress evaluation by means of both numerical methods (FEM) and experimental approaches.

This subject is included into study plan of the 3rd year of general bachelor's study as a compulsory-optional one. It is recommended as a prerequisite of branches M-ADI, M-ENI, M-FLI, M-IMB, M-MET or M-VSR.

Attendance at practical training is obligatory. Head of seminars carry out continuous monitoring of student's presence, their activities and basic knowledge.

Programme N-ENG-A: Mechanical Engineering, Master's
branch ---: no specialisation, 7 credits, compulsory

12 hours, compulsory

– Evaluation of stresses and deformations in bars under combined loads.
- Application of failure criteria for bars under combined loading.
- Stress state in a point of a body, principal stresses, failure criteria under multiaxial stress states.
- Criterion of unstable crack propagation, LEFM, estimation of the residual life.
- Limit state of fatigue fracture, endurance strength.
- Fatigue failure under non-symmetrical stress cycle.
- Fatigue under combined loading, safety under non-proportional loading.
- Thick-walled cylindrical vessels – stress-strain analysis.
- Rotating discs – stress-strain analysis.
- Axisymmetric plates – stress-strain analysis.
- Axisymmetric membrane shells – stress-strain analysis.
- Bending theory of cylindrical shells – stress-strain analysis.
- Course-unit credit.