Abstract:
There exists at the present time, a lack of experimental data, to translate by model, the differed behaviour of compacting concrete which constitute a new generation of materials.
To get these data, we must do a big number of tests.
Since its discovery in 1911, the creep of concrete was mainly studied under compressive load. The tensile or bending tests is rare.
The objective of this work is to make experimentally and numerically the deferred interest held before peak load (creep) beams made up with three different self-compacting concrete, solicited four-point bending behavior. Based on the analysis of measured arrows to show the influence of various parameters such as: the fineness of the limestone addition, the report filler / binder, and the rate of loading applied.
To arrive by following the confrontation between the experimental results and estimates of four American and European predictive models chosen for this study namely (ACI 209, B3, EC02, CEB MC90). To predict the flow correctly and verify the ability of the latter to reproduce the experimental deformations obtained for concrete other than ordinary concrete.
Were studied while being based on the analysis of the measured deflections for beams, in order to show the influence of various parameters such as: the fineness of the limestone addition , the report filler / binder, and the rate of loading applied.
A preliminary characterisation of the mechanical behaviour under monotonous loading of these varieties of concretes was realized for the determination of:
* failure load and deflection,
* And Elastic modulus.
The behaviour according to time is studied experimentally under different bending loads. The tests were systematically carried out at the age of 7 days under 20 ± 2 °C with RH = 55 ± 5%. The duration of loading is higher than 80 days for most tests.
We note that in this study, there is no separation between the basic creep and the drying creep.
Important results emerge:
* Loading rate applied and the fineness of the limestone addition have significant
effects on the creep of SCC, as compared to filler / binder its influence is less important.
* Analysis of the results of the comparison shows that even if all regulatory models underestimate the creep models that reproduce the best in the greatest number of cases, the measured deformations are the American models ACI end B3.
