Advertisement

Structural Effects of Time Dependent Behaviour of Concrete

Part of the International Centre for Mechanical Sciences book series (CISM, volume 316)

Abstract

The procedures for the linear viscoelastic analysis of R.C. and P.C. structures with particular emphasis to bridge-structures are presented. After a brief discussion of the fundamental properties of the constitutive linear viscoelastic law, based on the superposition integral, the two simplified models, namely the classical model and the Dischinger model are presented and widely discussed, stating their stress-strain laws of differential type. The numerical algorithms and the approximate techniques allowing to express in a convenient way for the applications the integral constitutive law are then introduced and a particular discussion is devoted to the algebraic approximate procedures. The homogeneous structures are then examinated and the basic theorems of linear viscoelasticity are deduced, showing the results deriving from an exact analysis when loads or imposed deformations or additional restraints are applied to the structure. As regards the non homogeneous structures the very important class related to the homogeneous viscoelastic structures with elastic restraints is studied. With reference to bridge structures this class is very important as it includes the cable-stayed bridges or the bridge beams with P.C. or steel-concrete transverse sections. The problem of the evaluation the state of stress in cable stayed bridges or in P.C. or steel concrete sections is approached by means of the unified procedure, stated by the author and called Reduced Relaxation Function Method, which is here applied in its direct or inverse form.

The method is explained in its fundamental aspects and approximate solutions of particular simplicity are suggested, defining the upper and lower bounds for the exact solution. In a wide number of actual cases these bounds are very close so that the approximate solutions can be recommended for practical purposes. Three numerical examples, related to cable stayed bridges and to a steel-concrete section are then discussed showing the marked effects of creep on the long term state of stress of this kind of bridge structures.

Keywords

Reinforce Concrete Creep Deformation Stress Path Homogeneous Structure Relaxation Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Troxell, G.E., Raphael, J.M., Davis, R.W.: Long Time Creep and Shrinkage tests of Plain and Reinforced Concrete, ASTM Proceedings, 58 (1958), 1–20.Google Scholar
  2. 2.
    Reichart, T.W.: Creep and Drying Shrinkage of Lightweight and Normal Weight Concretes, National Bureau of Standards, U.S.A. NBS Monograph 74 (1964), 1–30.Google Scholar
  3. 3.
    Hansen, T.C., Mattock, A.H.: Influence of Size and Shape of Member on Shrinkage and Creep of Concrete: ACI Journal 63 (1966) 267–289.Google Scholar
  4. 4.
    L’Hermite, R., Mamillan, M.: Retrait et Fluage des Betons,_ Annales ITBTP, Supplement 21, 1968.Google Scholar
  5. 5.
    L’Hermite, R., Mamillan M., Lefèvre, C.: Nouveaux Résultats de Recherches sur la Deformation et la Rupture du Béton, Annales ITBTP 18 (1965) 325–360.Google Scholar
  6. 6.
    Wei-Wen Yu, Winter, G,: Instantaneous and Long-Time Deflections of Reinforced Concrete Beams Under Working Loads, ACI Journal 57 (1960) 29–50.Google Scholar
  7. 7.
    Mamillan, M., Savin, V.: Etude Expérimentale sur le Fluage du Béton. Verification, du Principe de Superposition, Materiaux et Constructions, RILEM, Vol. 14, 81 (1981) 177–189.Google Scholar
  8. 8.
    Hanson, J.A.,: A 10-year Study of Creep Properties of Concrete, Concrete Laboratory Report N. Sp-38, U.S. Department of the Interior, Bureau of Reclamation, Denver, Colorado, 1953.Google Scholar
  9. 9.
    FIP (Federation Interantional de la Precontrainte) - CEB (Comité Eurointernational du Béton): Code Modèle pour les Structures en Béton. CEB Bulletin d’Information N. 124, 1978.Google Scholar
  10. 10.
    AASHTO, Standard Specifications for Highways Bridges, 11th Edn. 1467, AASHTO, Washington, D.C. 1973.Google Scholar
  11. 11.
    Italian Ministry of Public Works: Italian Building Code for R.C. and P.C. Structures, 1985, (in italian).Google Scholar
  12. 12.
    EH-82 Instruction para el Proyecto y la Ejecución de Obras de Hormigon en Masa o Armado, Comision Permanente del Hormigon, Madrid, 1986.Google Scholar
  13. 13.
    Mc Henry, D.: A new Aspect of Creep in Concrete and its Applciation to Design, Proceedings ASTM, 43 (1943) 1069–1086.Google Scholar
  14. 14.
    Ross, A.D.: Creep of Concrete under variable Stress, ACI Journal, Vol. 54 (1958) 739–758.Google Scholar
  15. 15.
    Maslov, G.N., Thermal Stresses in Concrete Masses with Account of Concrete Creep (in Russian), Gosenergoizdat, 28 (1940) 175–188.Google Scholar
  16. 16.
    ACI (American Concrete Institute) Committee 209: Prediction of Creep, Shrinkage and Temperature Effects in Concrete Structures, in: Designing for Effects of Creep, Shrinkage and Temperature in Concrete Structures. ACI Publication SP27–3 (1971) 41–93.Google Scholar
  17. 17.
    Rüsch, H., Jungwirth, D., Hilsdorf, H.,: Kritische Sichtung der Verfahren zur Berücksichtigung der Einflüsse von Kriechen und Schwinden des Betons, Beton und Stahlbetonbau, H. 68 (1973) 49–60; 76–86; 152–158.Google Scholar
  18. 18.
    Nowacki, W.: Theorie du Fluage, Eyrolles, Paris, 1965.Google Scholar
  19. 19.
    Persoz, B.: Introduction à l’Etude de la Rheologie, Dunod, Paris, 1960.Google Scholar
  20. 20.
    Bland, D.R.: Theory of Linear Viscoelasticity, Pergamon Press, Oxford, 1960.MATHGoogle Scholar
  21. 21.
    Dischinger, F.: Untersuchungen über die Knicksichereit, die Elastische Verformung und das Kriechen des Betons bei Bogenbrücken, Der Bauingenieur H. 18 (1937) 487–520; 539–552; 595–621. H. 20 (1939) 53–63; 286–294; 426–437; 563–572.Google Scholar
  22. 22.
    Whitney, C.S.: Plain and Reinforced Concrete Arches, ACI Journal Vol. 28 (1932) 479–519.Google Scholar
  23. 23.
    Glanville, W.H.: The Creep or Flow of Concrete under Load, Studies in Reinforced Concrete, part III, Dept. Scientific and Industrial Research, Building Research Technical Paper N. 12, London (1930).Google Scholar
  24. 24.
    FIP-CEB Manual on Structural Effects of Time-dependent Behaviour of Concrete, CEB Bulletin d’Information N. 142–142bis, Georgi Publishing Co. Saint-Saphorin, CH 1984.Google Scholar
  25. 25.
    Rösch, H., Jungwirth, D: Stahlbeton Spannbeton, Band 2, Werner Verlag, Düsseldorf 1976.Google Scholar
  26. 26.
    Branson, D.E.: Deformation of Concrete Structures, Mc Graw-Hill, New York, 1977.Google Scholar
  27. 27.
    Trost, H.: Auswirkungen des Superposition Prinzips auf Kriech und Relaxation Probleme bei Beton und Spannbeton, Beton und Stahlbetonbau H. 62 (1967) 230–238.Google Scholar
  28. 28.
    Bazant, Z.P.: Prediction of Concrete Creep Effects Using Age-Adjusted Effective-Modulus method, ACI Journal, Vol. 69 (1972) 212217.Google Scholar
  29. 29.
    Mola, F.: Methods for the analysis of linear viscoelastic structures, Studi e Ricerche Vol. 3 Italcementi Bergamo (Italy) (in italian) (1981).Google Scholar
  30. 30.
    Mola, F.: Linear viscoelastic analysis of non homogeneous structures, Studi e Ricerche vol. 8 Italcementi Bergamo (Italy) (in italian) (1986) 119–196.Google Scholar
  31. 31.
    Mola, F., Malerba, P.G., Pisani, M.A. Creep and Shrinkage Effects on the Cable-Stayed Bridges Behaviour, Proceedings of the International Conference on Cable-Stayed Bridges, Vol. 1, Bangkok, Thailand, (1986) 657–667.Google Scholar
  32. 32.
    Mola, F., Malerba, P.G., Pisani, M.A.! Structural non homogeneity and additional restraints effects on the long term behaviour of precast R.C. or P.C. Bridges, Proceedings of the Symposium of the Italian R.C. and P.C. Association, Vol. 2, Stresa Italy (1987) 505519 (in italian).Google Scholar
  33. 33.
    Mola, F.: Applications of the Reduced Relaxation Function Method to the Analysis of homogeneous viscoelastic structures, Studi e Ricerche Vol. 4 Italcementi Bergamo (Italy) (in italian) (1982) 211–235.Google Scholar

Copyright information

© Springer-Verlag Wien 1991

Authors and Affiliations

  • F. Mola
    • 1
  1. 1.Politechnic of MilanMilanItaly

Personalised recommendations