Course code LauZ3162

Credit points 3

Total Hours in Course81

Number of hours for lectures16

Number of hours for seminars and practical classes8

Number of hours for laboratory classes8

Independent study hours49

Date of course confirmation05.12.2012

Responsible UnitInstitute of Mechanics and Design

Dr. sc. ing.

prof.
## Aivars Kaķītis

Dr. sc. ing.

lect.
## Mārtiņš Dauvarts

Bc. sc. ing.

LauZ3127 [GLAU3127] Strength of Materials II

The aim of the study course is to acquire basic knowledge about the strength of materials and methods of its determination, as well as about the methods of calculation of the basic elements of structures. In this part of the course, calculations of structural deformations, combined loads, statically indeterminate systems, buckling, dynamic and impact loads are mastered.

Knowledge - students learn the principles of engineering calculations of strength, durability and deformation of materials and structures. Assessment - tests and defense of individual works.

Skills - students are able to creatively use the principles and methods and techniques of material resistance in the calculation of strength, stability and deformation of engineering structures. Assessment - defense of individual and laboratory works.

Competence - students are able to independently solve engineering problems, create calculation schemes for real structures and perform the necessary calculations for equipment design work. Assessment - defense of individual and laboratory works.

1. Energy methods for deformation calculation. Castilliano's theorem, its applications - 2h.

2. Mohr’s integral, its use in deformation calculations - 2h.

3. Vereshchagin’s method, its use in deformation calculations - 2h.

4. Calculation of elastic displacements in bending, examples - 2h (Practical work).

5. Determination of elastic displacements - 2h (Laboratory work).

6. Test on the calculation of elastic displacements

7. Compound loads. Unsymmetrical bending. Stress and strain calculations - 2h.

8. Determination of deformations in unsymmetrical bending - 2h (Laboratory work).

9. Compound loads. Bending + torsion - 2h.

10. Calculation of drive shaft under load bending + torsion - 2h (Practical work).

11. Determination of stress state in composite load bending + torsion - 2h. (Laboratory work).

12. Statically indeterminate systems. Canonical equations of the force method - 2h.

13. Single and double statically indeterminate systems. Examples of solutions - 2h. (Practical work).

14. Buckling. Euler's formula for determining critical force, its use. Coefficient φ method for determining the dimensions of the bar in buckling - 2h.

15. Strength calculation in buckling. - 2h (Practical work).

16. Research of the buckling process. - 2h (Laboratory work).

17. Estimation of inertial forces in calculations. Dynamic and impact loads. Material fatigue. Durability calculations - 2h.

18. Test on calculation of durability of structures.

The course ends with an exam. In order to pass the exam, independent work and laboratory works must be defended and tests must be written.

During the independent work students study in depth the topics discussed in the lectures and perform independent work:

1. Independent work: Calculate the bending deformation of the beam at a given point using two methods.

2. Independent work: Calculate the dimensions of the drive shaft under load bending + torsion.

3. Independent work: Calculate once statically indeterminate flat frame strength.

4. Independent work: Calculate the strength of the beam in buckling.

A successful assessment can be obtained in the test if there are no significant errors in the calculations and the process of the calculations is explained. The student receives high marks if the tasks performed in the laboratory and independent works are completed, well-designed and the student is able to answer the questions.

1. Ziemelis I., Kaķītis A., Dominieks L. Materiālu pretestība. Jelgava: LLU, 2008. 376 lpp.

2. Russell Hibbeler. Statics and Mechanics of Materials. Pearson; 5th edition, 2016. 936 p.

1. Materiālu pretestība: mācību grāmata augstskolu tehnisko specialitāšu studentiem / E. Lavendelis. Rīga: Zvaigzne, 1986, 340 lpp.

Lekcijas un e-studiju materiāli

The study course is included in the Compulsory part of the Bachelor’s study program “Agricultural Engineering”. 3rd study year 5th semester.