Evaluation of time dependent prestress losses in pretensioned concrete member with top and bottom tendons

• Autorzy: Parkhats Vadzim , Krzywoń Rafał

Identyfikatory

DOI

10.21307/ACEE-2019-040

• Języki publikacji: EN

Abstrakty

EN

Prestress losses are usually calculated by bringing the tendons in the cross-section to the single resultant tendon. This solution is correct only for tendons concentrated in one part of the cross-section, while with their wider distribution, for example after the use of upper tendons, it may result in underestimation of losses in the lower tendons and overestimation in the upper tendons. The paper presents formulae to determine time dependent prestress losses separately for the top and bottom tendons of a pretensioned concrete member. Furthermore, variations of stress in the prestressing steel are analysed for two pretensioned concrete members to evaluate the possibility of using the equation (5.46) from the Eurocode 2 for the resultant tendon instead of the deduced formulae. The aim of this study is to show how great the error of estimated loss of prestressing force on the basis of several typical prestressed concrete sections can be.

Słowa kluczowe

EN

creep; prestress loss; pretensioned concrete member; relaxation; shrinkage; stress in prestressing reinforcement; tendons

PL

pełzanie; strata sprężenia; element strunobetonowy; relaksacja; skurcz; naprężenie w zbrojeniu sprężającym; cięgno

• Wydawca: Silesian University of Technology
• Czasopismo: Architecture Civil Engineering Environment
• Rocznik: 2019
• Tom: Vol. 12, no. 3
• Strony: 105--112
• Opis fizyczny: Bibliogr. 9 poz.

Twórcy

autor

Parkhats Vadzim

• MSc; Silesian University of Technology, Faculty of Civil Engineering, Department of Structural Engineering, Akademicka 5, 44-100 Gliwice, Poland

autor

Krzywoń Rafał

• PhD; Silesian University of Technology, Faculty of Civil Engineering, Department of Structural Engineering, Akademicka 5, 44-100 Gliwice, Poland

Bibliografia

• [1] Caro, L. A., Marti-Vargas, J. R., & Serna, P. (2013). Prestressed losses evaluation in prestressed concrete prismatic specimens. Engineering Structures, 48, 704-715.
• [2] Chandoga, M., Halvonik, J., & Pritula, A. (2009). Time depending deformation of pre-post tensioned beams. Architecture Civil Engineering Environment, 2(4), 51-60.
• [3] Comite Euro-International du Beton (CEB), Federation Internationale de la Precontrainte (FIP) (1978). Model Code for Concrete Structures. Paris: CEB, 348 pp.
• [4] EN 1992-1-1 (2004). Eurocode 2: Design of concrete structures - Part 1-1: General rules and rules for buildings. Brussels: CEN.
• [5] Dyduch, K. (2015). Analiza opóźnionych strat sprężenia w konstrukcjach z betonu (Analysis of timedependent prestress losses in concrete structures). In W. Derkowski, P. Gwoździewicz, M. Pańtak, W. Politalski, A. Seruga, & M. Surma (Eds.), Konferencja Naukowo-Techniczna KS2015 Konstrukcje Sprężone. Kraków.
• [6] Bazant Z. P. (1972). Prediction of Concrete Creep Effects Using Age-Adjusted Effective Modulus Method. ACI Journal, 69(4), 212-217.
• [7] Dilger W. H. (1982). Creep Analysis of Prestressed Concrete Structures Using Creep Transformed Section Properties. PCI Journal, 27(1), 89-117.
• [8] Ghali A., Trevino J. (1985). Relaxation of Steel in Prestressed Concrete. PCI Journal, 30(5), 82-94.
• [9] EN 1990:2002+A1 (2005). Eurocode - Basis of structural design. Brussels: CEN.

Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).