Materials and Structures

, 35:28 | Cite as

Size effect of test specimens on tensile splitting strength of concrete: general relation

  • Vl. Kadleček
  • S. Modrý
  • Vl. KadlečekJr.
Scientific Reports

Abstract

A broad experimental program was carried out on cubes, cylinders and prisms (loaded transversally or longitudinally) of sizes usually used in laboratory testing. For casting, concrete mixes of various compositions were used. The 1600 results obtained were evaluated by mathematical statistical methods. The volume of test specimens was substituted either by the size of the corresponding fracture area or by the size of the highly stressed volume (HSV) in their loaded cross-section. The absolute values of the tensile splitting strength were converted to relative values (depending on the basic size of the fracture area or on the highly stressed volume). For mathematical expression of the relationships between these quantities, an exponential function was used. This relation enables to convert the test results obtained on specimens of different sizes and shapes to the strength of the basic size specimen. This is important for the test results obtained on samples taken from finished structures, as these samples are usually of different sizes.

Keywords

Stressed Volume Test Specimen Fracture Area Coarse Aggregate Tensile Splitting Strength 

Résumé

Un vaste programme expérimental, dans le cadre duquel des essais ont été effectués sur des cubes, des cylindres et des prismes (chargés de façon transversale ou longitudinale) a été réalisé avec des dimensions habituelles pour des essais en laboratoire. Pour la confection des éprouvettes, des mélanges de béton de composition différente ont été utilisés. Les 1 600 résultats obtenus ont été évalués par des méthodes de statistique mathématique. Le volume des éprouvettes d'essais a été remplacé soit par la taille de la surface de la section de rupture correspondante, soit par la taille du volume de plus grande contrainte (HSV) dans la section chargée. Les valuers absolues de la résistance en traction par fendage ont été converties en valuers relatives (dépendantes de la taille de base de la surface de la section de rupture ou de celle du volume de plus grande contrainte). Pour effecteur le calcul mathématique concernant la relation entre ces valeurs. une fonction exponentielle a été utilisée. Cette relation permet d'appliquer les résultats d'essais obtenus sur les éprouvettes de tailles et de formes différentes à la résistance de l'éprouvette de taille de base. C'est ce qui est important en ce qui concerne les résultats des essais obtenus sur les échantillons extraits de constructions achevées, ces demiers ayant dans la plupart des cas des tailles différentes.

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Copyright information

© RILEM 2002

Authors and Affiliations

  • Vl. Kadleček
    • 1
  • S. Modrý
    • 1
  • Vl. KadlečekJr.
    • 2
  1. 1.Klokner InstituteCzech Technical UniversityPragueCzech Republic
  2. 2.Technical and Testing Institute for ConstructionsPragueCzech Republic

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