Course Details

Prestressed Concrete

Academic Year 2024/25

BL011 course is not part of any programme in the faculty

Course Guarantor

Institute

Language of instruction

Czech

Credits

5 credits

Semester

winter

Forms and criteria of assessment

course-unit credit and examination

Offered to foreign students

Not to offer

Course on BUT site

Lecture

13 weeks, 2 hours/week, elective

Syllabus

1. Basic concept of prestressing. Behaviour of non-prestressed and prestressed concrete beams. Material properties of concrete. 2. Prestressing tendons and bars. Prestressing technology, basic terminology. Pretensioned concrete. 3. Post-tensioning operations, technology, prestressing systems. 4.-5. Losses of prestressing of pretensioned and post-tensioned concrete. Construction and serviceability stages. 6. Effects of prestressing. Equivalent load method. Concordant tendon, transformation of tendon. 7. Design of prestressing - load balanced method. Allowable stresses. Crack resistance. 8. Structural analysis of step-by-step built structures, non-homogeneity of structures. Creep analysis. 9. Ultimate limit state of prestressed members loaded by axial force and bending moment, decompression state, initial state of stress. 10. Prestressed members loaded in shear and torsion, stress analysis, proportioning. 11. Anchorage zone analysis, calculation model, check of resistance, proportioning. 12. Serviceability limit states (SLS). Crack resistance, tensile stresses in the concrete after cracking. 13. Control of crack width of prestressed members. Control of deflection.

Exercise

13 weeks, 2 hours/week, compulsory

Syllabus

1. Post-tensioned bridge beam - design: Load, design of a cross section, material characteristics, types of anchors, structural principles, design of prestressing force and its eccentricity. 2. Verification of prestressing force design via loads effects compensation method, design of cables and their trajectory. 3. Effects of prestressing on the structures - examples. 4. Post-tensioned bridge beam - design (continuation): Effects of load, initial (anchoring) stress, immediate changes of prestressing. 5. Simplified calculation of time-dependent changes of prestressing. Time behaviour of prestressing force magnitude. 6. Correction. 7. Serviceability limit states – limit state of stress and cracks limitation (decompression). 8. Ultimate limit state – bending moment. 9. Ultimate limit state - shear, design of shearing reinforcement. 10. Verification of anchors, design of reinforcement in the anchoring area, drawing of active and passive reinforcement. 11. Serviceability limit states – deflection of a beam. Correction. 12. Effects of prestressing on the structures (continution): Effect of prestressing on the structures progressively erected - examples. 13. Design submission. Credit.