Chapter 3 - EXPERIMENTAL PROGRAM
Stress - Displacement (middle) - 28 days 12 1_FRM_0° 2_FRM_0°
10
3_FRM_0° 1_FRM_30°
σ [MPa]
8
2_FRM_30° 1_FRM_45°
6
2_FRM_45° 4
3_FRM_45° 1_FRM_60°
2
2_FRM_60° 1_FRM_90°
0
2_FRM_90° 0
1
2
3
4
5
6
3_FRM_90°
Displacement [mm] Figure 3.2.29 – Stress – Displacement behavior at 28 days.
The same operations were repeated for the samples at 50 days, however in this case, the absolutely casual presence of voids has revealed to be so significant as to disturb the reader’s comprehension. Thus, it was decided to report the tests data obtained from the 50 days samples in Annex A and consider more reliable the ones obtained at 28 days. In particular this decision is even more justified by the table showed below that highlights that all the 50 days specimens are more lightweight than the 28 days specimens due to the higher presence of voids. In conclusion, the behavior showed in Figure 3.2.29 will be considered representative of the FRM vertical casted, however a numerical comparison with the data obtained at 50 days of curing will not be avoided in next sections in order to demonstrate how the voids presence influences the flexural strength.
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