Non-linear finite element analysis of shear critical high strength concrete beams

• Autorzy: Sagaseta J. , Vollum R.
• Języki publikacji: EN

Abstrakty

EN

Experimental evidence shows that the bond between the aggregate and cement paste can be sufficiently strong in highstrength concretes for cracks to pass through the aggregate. Cracks that pass through coarse aggregate are smooth and significantly reduce the potential for shear transfer through aggregate interlock action. Current design methods for shear do not take the aggregate type into consideration. This paper describes a series of non-linear finite element analyses the authors carried out to assess the influence of crack roughness on the shear strength of beams. The models incorporated both smeared and discrete cracking elements. The numerical models were validated with data from 22 beams tested at Imperial College London. In general, the ultimate load, crack patterns and relative crack displacements were satisfactorily reproduced. The reduction in strength due to aggregate fracture was found to be greatest in slender beams without stirrups and insignificant in short span beams where the cracks tended to open rather than slide.

PL

Badania doświadczalne wskazują, że w betonie wysokiej wytrzymałości siły przyczepności pomiędzy kruszywem i zaczynem cementowym mogą być na tyle duże aby zarysowanie powstawało w kruszywie. Rysy przechodzące przez kruszywo są gładkie i znacząco redukują zdolność do przenoszenia sił tnących poprzez zazębianie się kruszywa. W artykule przedstawiono nieliniowe analizy numeryczne, przeprowadzone przez autorów w celu oceny wpływu charakteru zarysowania na nośność na ścinanie belek. Analizy wykonano zarówno dla modelu z rozmytym jak i dyskretnym obrazem zarysowania. Modele numeryczne zostały porównane z wynikami badań 22 belek. Największe obniżenie nośności na ścinanie spowodowane zniszczeniem kruszywa obserwowano w belkach smukłych, nie zbrojonych strzemionami.

Słowa kluczowe

EN

aggregate interlock; high-strength concrete; non-linear finite element analysis; shear design

PL

zazębianie kruszywa; beton o dużej wytrzymałości; analiza nieliniowa metodą elementów skończonych; projektowanie nośności na ścinanie

• Wydawca: Silesian University of Technology
• Czasopismo: Architecture Civil Engineering Environment
• Rocznik: 2009
• Tom: Vol. 2, no. 4
• Strony: 95--105
• Opis fizyczny: Bibliogr. 17 poz.

Twórcy

autor

Sagaseta J.

autor

Vollum R.

• Ecole Polytechnique Federale de Lausanne (EPFL),

Bibliografia

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