Czech

5

Institute of Concrete and Masonry Structures (BZK)

Understanding of the behavior of prestressed concrete structures.
Knowledge of calculation of effect of prestressing on statically determinate structures and statically indeterminate structures.
Knowledge of pre-tensioning technology and post-tensioning technology.
Design and construction of prestressed concrete structural members and structural systems, analysis and detailing:
- design of tendon trajectory and magnitude of prestressing force (methods of design)
- calculation of losses
- assessment by ultimate limit state and serviceability limit state.

structural mechanics, theory of elasticity, plasticity, concrete members and concrete structures

do not required

Teaching methods depend on the type of course unit as specified in the article 7 of BUT Rules for Studies and Examinations. Education runs in the forms of lectures and trainings. Character of the lectures is based on definition of basic principles, problems and methodology. In the trainings the main subject matters are trained on individually defined projects (examples).

To gain the credit, the students should elaborate individually defined design and calculate specified task. The students are obliged to consult the design continuously in the given terms and submit it to the fixed date. The presences in training lessons are checked. An exam consists both of the written part, in which the task is elaborated, and the theoretical part. To pass the exam successfully, both parts should be accomplished.

1. Introduction, basic concept of prestressing. Behaviour of non-prestressed and prestressed concrete beams. Material properties of concrete.
2. Material properties of prestressing tendons and bars, manufacturing, mechanical properties, types. Prestressing technology, basic terminology. Pretensioned concrete.
3. Post-tensioning operations, technology, prestressing systems.
4. Losses of prestressing. Frictional loss, anchorage set loss.
5. Losses of prestressing due to elastic concrete deformation, relaxation of prestressing reinforcement, creep and shrinkage. Construction and serviceability stages.
6. Effects of prestressing. Equivalent load method, statically determinate and indeterminate structures, concordant tendon, linear transformation of tendon.
7. Design of prestressing - load balanced method. Allowable stresses, allowable zone of prestressed tendon, and line of pressure. Crack resistance.
8. Structural analysis of step-by-step built structures, non-homogeneity of structures. Creep analysis – analytic solution.
9. Ultimate limit state (ULS) of prestressed members loaded by axial force and bending moment, decompression state, initial state of stress. Secondary effects of prestressing at ULS of the structures.
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.

Not applicable.

Understanding of the behaviour of prestressed concrete structures. Design of prestressed concrete structural members and structural systems, analysis and detailing.

Extent and forms are specified by guarantor’s regulation updated for every academic year.

Not applicable.

Not applicable.

VOVES, Bohumír: Navrhování konstrukcí z předpjatého betonu v příkladech. Praha: SNTL, 1980. (CS)
LIN, T. Y. a BURNS, Ned H.: Design of Prestressed Concrete Structures. New York: John Wiley & Sons, 1981. ISBN 0471018988. (EN)
COLLINS, Michael P. a MITCHELL, Denis: Prestressed Concrete Structures. New Jersey: Prentice Hall, 1991. ISBN 0-13-691635-X. (EN)
ROMBACH, Günter: Spannbetonbau. Berlin: Ernst und Sohn, 2010. ISBN 978-3-433-02911-4. (DE)

KLUSÁČEK, Ladislav, PANÁČEK, Josef a ŠTĚPÁNEK, Petr: Betonové konstrukce. Předpjatý beton podle ČSN 73 1201. Brno: VUT, 1991. ISBN 80-214-0267-9. (CS)
GERWICK, Ben C.: Construction of Prestressed Concrete Structures. USA: John Wiley and Sons, 1997. ISBN 978-0-471-18113-2. (EN)
NAVRÁTIL, Jaroslav a ZICH, Miloš.: Předpjatý beton (průvodce předmětem v elektronické podobě). Brno: VUT, 2006. (CS)
NAVRÁTIL, Jaroslav: Předpjaté betonové konstrukce. Brno: CERM, 2008. ISBN 978-80-7204-561-7. (CS)
NAVRÁTIL, Jaroslav a ŠTĚPÁNEK, Petr: Předpjaté stavební konstrukce. Modul M01 (část studijní opory v elektronické podobě). Brno: VUT, 2009. (CS)
PROCHÁZKA, Jaroslav a kol.: Navrhování betonových konstrukcí podle norem ČSN EN 1992 (EUROKÓDU 2). Část 2: Předpjatý beton. Praha: ČBS Servis, 2010. ISBN 978-80-87158-21-0. (CS)

13 hours, compulsory

1. Effect of prestressing on statically determinate structures. Students are to solved tasks individually.
2. Effect of prestressing on statically indeterminate structures. Students are to solved tasks individually.
3.- 4. Project: Design and assessment of prestressed roof girder. Action and combination of loads, design of cross-section, characteristics of materials, types of prestressing steels, structural requirements.
5.– 6. Continuation of project. Design of eccentricity and magnitude of prestressing force, design of amount of prestressed strands.
7. Continuation of project. Immediate (short-term) losses of prestress.
8. Continuation of project. Long-term (time dependent) losses of prestress.
9.– 10. Continuation of project. Verification of design by serviceability limit state – stress limitation, crack control.
11. Continuation of project. Verification of design by ultimate limit state – bending moment.
12. Continuation of project. Scheme of girder reinforcement by prestressing strands.
13. Project and tasks submission. Credit.