Course detail

Selected problems of concrete structures I (KON)

FAST-CL53Acad. year: 2019/2020

Static analysis of concrete structures and their parts. Plasticity method, lower-bound theorem, upper-bound theorem. Truss analogy for the analysis of concrete structures, material properties.
Truss analogy application for reinforcement design of some structures and details. Analysis of beams loaded in shear, variable angle truss model, modern theories of interaction of internal forces acting on concrete section.
Compression field theory, modified compression field theory.
Physical principles of creep, shrinkage and ageing of concrete drying up of concrete, solution of state of stress from temperature load. Principles of linearity (stress, temperature), and superposition, stress history. Creep models – assumptions, mathematical functions, properties. Ageing of concrete. Integral and differential equations, affinity of creep, stress history. Non-homogeneity of structures. Force method for creep analysis.
Structural analysis of step-by-step constructed structures. The influence of prestressing, step-by-step construction, and rheological effects on structures.
Some simplified and numerical methods for creep analysis and their combination by FEM.
Design of concrete structures exposed to fire. The behaviour of materials during effects of fire. Design approaches. Simplified and updated computational methods for structures exposed to the fire.

Language of instruction

Czech

Number of ECTS credits

4

Guarantor

prof. RNDr. Ing. Petr Štěpánek, CSc., dr. h. c.

Department

Institute of Concrete and Masonry Structures (BZK)

Learning outcomes of the course unit

A student gains these knowledge and skills:
• Understanding of the principles of concrete plasticity and its application in concrete structures design.
• Knowledge of the modern methods of design of the members stressed by shear and torsion, optionally in interaction with others types of internal forces.
• Understanding of the principles of rheological effects of concrete and mastering the methods for analysis of these effects on constructions.
• Understanding of the methods for analysis of long-term effects of concrete and composite structures in view of the rheological properties of concrete.

Prerequisites

structural mechanics, numerical methods, concrete structures, prestressed concrete

Co-requisites

Not applicable.

Planned learning activities and teaching methods

Not applicable.

Assesment methods and criteria linked to learning outcomes

Not applicable.

Course curriculum

1. The interrelation of design and structural model. Plastic analysis. Strut and tie model. Proportioning of nodes, struts and ties.
2. Truss analogy - Reinforcement design of brackets, corbels and discontinuity zones.
3. Variable angle truss model, interaction of internal forces acting on concrete cross-section.
4. Hybrid structures. Influence of rheology of concrete on structural behaviour. Drying of concrete, shrinkage, autogenous shrinkage, physical principal of rheological phenomena. Effects of creep and shrinkage on structural behaviour, non-homogeneity of structures. Colonnetti’s theorems.
5. Components of concrete strain. Delayed strain caused by stress. Principle of linearity (stress, temperature) and superposition, stress history, ageing of concrete.
6. Simplified and numerical methods for the analysis of rheological effects on structures – effective modulus methods, effective time method.
7. Time discretization method, its combination with finite element method.
8. Structural analysis of progressively constructed prestressed structures. Closed form solution using force method. The practical implications of creep and shrinkage on structures.
9. Temperature effects on concrete - calculation of temperature stress acting on the structure.
10. Experimental structural analysis, model similarity.
11. Design of concrete structures exposed to fire. The effect of the fire to the structure. Determination of fire resistance.
12. The behaviour of materials during effects of fire. Design approaches.
13. Updated computational methods of structures exposed to the fire.

Work placements

Not applicable.

Aims

Understanding of the principle of concrete plasticity and its application in design of concrete structures.
To provide the students with the modern methods of design of the members loaded in shear and torsion, optionally in interaction with other components of internal forces.
Understanding of the principles of rheological effects of concrete and mastering the methods for analysis of these effects on structures.
Understanding of the methods for analysis of long-term effects of concrete and composite structures in view of the rheological properties of concrete.

Specification of controlled education, way of implementation and compensation for absences

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

Recommended optional programme components

Not applicable.

Prerequisites and corequisites

Not applicable.

Basic literature

BAŽANT, Zdeněk P. a L´Hermite, Robert: Mathematical Modelling of Creep and Shrinkage of Concrete. New York: John Wiley and Sons, 1988. ISBN 0471920576. (EN)
ŠMERDA, Zdeněk a KŘÍSTEK, Vladimír: Creep and Shrinkage of Concrete Elements and Structures. Praha: SNTL, 1988. (CS)
COLLINS, Michael P. and MITCHELL, Denis: Prestressed Concrete Structures. New Jersey: Prentice Hall, 1991. ISBN 0-13-691635-X. (EN)
NAVRÁTIL, Jaroslav: Prestressed Concrete Structures. Brno: CERM, 2006. ISBN 80-7204-462-1. (EN)
HSU, Tomas. T. C. a MO, Y. L.: Unified Theory of Concrete Structures. Chichester, UK: John Wiley & Sons, 2010. ISBN: 978-0-470-68874-8. [http://onlinelibrary.wiley.com/doi/10.1002/9780470688892.ch1/summary] (EN)
GHALI, Amin, FAVRE, Renaud a ELBADRY, Mamdouh: Concrete Structures. Stresses and Deformations: Analysis and Design for Sustainability. London: Spon Press, 2012. ISBN 978-0-415-58561-3. (EN)

Recommended reading

ZŮDA, Karel: Výpočet staticky neurčitých mostních konstrukcí z předpjatého betonu. Praha: SNTL, 1971. (CS)
ŠMERDA, Zdeněk a KŘÍSTEK, Vladimír: Dotvarování a smršťování betonových prvků a konstrukcí. Praha: SNTL, 1978. (CS)
VOVES, Bohuslav: Navrhování konstrukcí z předpjatého betonu v příkladech. Praha: SNTL, 1980. (CS)
SCHLAICH, Jorg, SCHAFER, Kurt a JENNEWEIN, Mattias: Towards a Consistent Design of Reinforced Concrete Structure. PCI Journal, Vol. 32, No. 3, 1987. ISSN: 0887-9672. [http://www.pci.org/publications/journal/archive.cfm?bv=1&season=May-June&year=1987] (EN)
MUTTONI, Aurelio, SCHWARTZ, Joseph a THÜRLIMANN, Bruno: Design and Detailing of Reinforced Concrete Structures. Switzerland: Swiss Federal Institute of Technology, 1989. (EN)
FIB Recommendations: Practical Design of Structural Concrete. London: SETO, 1999. (EN)
NAVRÁTILl, Jaroslav: Vybrané statě z betonových konstrukcí I (studijní opora v elektronické podobě). Brno: VUT, 2008. (CS)
NAVRÁTIL, Jaroslav: Předpjaté betonové konstrukce. Brno: CERM, 2008. ISBN 978-80-7204-561-7. (CS)
PROCHÁZKA, Jaroslav, ŠTEFAN, Radek a VAŠKOVÁ, Jitka: Navrhování betonových a zděných konstrukcí na účinky požáru. Praha: ČVUT, 2010. ISBN 978-80-01-04613-5. (CS)
Fib: Model Code 2010 - Final draft, Volume 2.. Lausanne: International Federation for Structural Concrete (fib), 2012. ISBN 978-2-88394-106-9. (EN)
Fib: Model Code 2010 - Final draft, Volume 1.. Lausanne: International Federation for Structural Concrete (fib), 2012. ISBN 978-2-88394-105-2. (EN)

Type of course unit

 

Lecture

26 hours, optionally

Teacher / Lecturer

prof. RNDr. Ing. Petr Štěpánek, CSc., dr. h. c.

Syllabus

1. The interrelation of design and structural model. Plastic analysis. Strut and tie model. Proportioning of nodes, struts and ties. 2. Truss analogy - Reinforcement design of brackets, corbels and discontinuity zones. 3. Variable angle truss model, interaction of internal forces acting on concrete cross-section. 4. Hybrid structures. Influence of rheology of concrete on structural behaviour. Drying of concrete, shrinkage, autogenous shrinkage, physical principal of rheological phenomena. Effects of creep and shrinkage on structural behaviour, non-homogeneity of structures. Colonnetti’s theorems. 5. Components of concrete strain. Delayed strain caused by stress. Principle of linearity (stress, temperature) and superposition, stress history, ageing of concrete. 6. Simplified and numerical methods for the analysis of rheological effects on structures – effective modulus methods, effective time method. 7. Time discretization method, its combination with finite element method. 8. Structural analysis of progressively constructed prestressed structures. Closed form solution using force method. The practical implications of creep and shrinkage on structures. 9. Temperature effects on concrete - calculation of temperature stress acting on the structure. 10. Experimental structural analysis, model similarity. 11. Design of concrete structures exposed to fire. The effect of the fire to the structure. Determination of fire resistance. 12. The behaviour of materials during effects of fire. Design approaches. 13. Updated computational methods of structures exposed to the fire.

Exercise

26 hours, compulsory

Teacher / Lecturer

prof. RNDr. Ing. Petr Štěpánek, CSc., dr. h. c.

Syllabus

1. Deep wall beam - solving by truss analogy method. 2. Short bracket (corbel) - solving by truss analogy method. 3.- 4. Calculating of the effects of creep on concrete structures - principle of superposition. 5.- 6. Assessment of the limit of normal stresses from the operating effects of prestressing on the bridge structure - the use of force method for creep calculation. 7. Correction. 8.- 9. Calculation of stress in the concrete sections of composite columns by time discretization analysis (basic method TDA). 10. Correction. 11. Possibility of modelling of the creep effect on concrete structures - practical exercises. 12. Final correction. 13. Design submission. Credit.