Validation of the fib 2010 and RILEM B4 models for predicting creep in concrete

• Autorzy: Fanourakis G.
• Języki publikacji: EN

Abstrakty

EN

Creep strain, a requirement of the concrete design process, is a complex phenomenon that has proven difficult to model. Although laboratory tests may be undertaken to determine the creep, these are generally expensive and not a practical option. Hence, empirical code-type prediction models are used to predict creep strain. This paper considers the accuracy of both the relatively new international fibModel Code 2010 and RILEMModel B4, when compared with the actual strains measured on a range of concretes under laboratory-controlled conditions. Both models investigated under-estimated the creep strain. In addition, the MC 2010 Model, which yielded an overall coefficient of variation (ωall) of 50.4%, was found to be more accurate than the RILEM B4 Model (with a ωall of 102.3%).

PL

Odkształcenia pełzania, których znajomość jest niezbędna w procesie projektowania, są złożone i trudne do przewidywania. Można przeprowadzić testy laboratoryjne w celu określenia pełzania, jednak są one generalnie kosztowne. W związku z tym w projektowaniu stosowane są modele empiryczne dostępne w normach. W artykule analizowano dokładność stosunkowo nowego międzynarodowego modelu pełzania przedstawionego w Model Code 2010 i RILEM B4, w porównaniu z rzeczywistymi odkształceniami pełzania mierzonymi w betonach dojrzewających w warunkach laboratoryjnych. Model MC 2010, który przyniósł całkowity współczynnik zmienności (ωall) wynoszący 50.4%, okazał się być dokładniejszy niż RILEM B4 (z ωall 102.3%).

Słowa kluczowe

EN

creep; concrete; codes; MC2010; RILEM B4

PL

pełzanie; beton; normy; MC2010; RILEM B4

• Wydawca: Silesian University of Technology
• Czasopismo: Architecture Civil Engineering Environment
• Rocznik: 2017
• Tom: Vol. 10, no. 3
• Strony: 95--101
• Opis fizyczny: Bibliogr. 25 poz.

Twórcy

autor

Fanourakis G.

• Department of Civil Engineering Technology, University of Johannesburg, PO Box 17011, Doornfontein, 2028, South Africa

Bibliografia

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