engleski

Deformational Properties of High Strength Concrete Predicted According to Eurocode 2

This study deals with experimental results of deformational properties of high strength concrete in comparison with values predicted according to Eurocode 2 (ENV 1992-1-1). Observed deformational properties are modulus of elasticity, shrinkage and creep. Four different mixtures of concrete were made, each represented by at least 16 samples. Time dependent properties as creep and shrinkage were conducted during 48 days after loading or finish of curing (7th day), at early age of hardened concrete. Modulus of elasticity was tested at the time of loading specimens for creep experiment, at the age of 28 days and at the age of six months and more. As obtained strengths tested on cylinders were higher then 50 MPa (up to 72 MPa), these concretes were considered as high strength concretes. This kind of high strength concrete was made only with the addition of superplasticizer to ingredients of normal strength concrete. This type of concrete is very often in use recenly. The test results obtained from this research were compared with equations given in different recommendations, models and codes such as ACI 209R-92, Eurocode and Model Code 90. This comparison shows that current equations are not applicable to our results. It also shows that expressions given in Eurocode 2 don't evaluate quantity of cement in the concretes of the same consistency in the proper way. The results of these tests stress the importance to determine experimentally deformational properties using the locally available materials for the specific high strength concrete.

deformational properties; high strength concrete; modulus of elasticity; shrinkage; creep

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