PSI - Issue 11

Stefanie A. Campos et al. / Procedia Structural Integrity 11 (2018) 145–152 Stefanie A. Campos et al./ Structural Integrity Procedia 00 (2018) 000–000

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to the hot test simulating the accelerated aging of the reactions. At 14 days, the percentage of hot expansion was 0.22%, but despite that, no cracks were found either in the cold expansion or in the specimens submitted to the hot test. In the analysis of the expansion by the method of the DNIT standard 113, values were obtained that were much higher than those obtained by the other methods, with the expansion rate of 1.8% at 14 days, but this value is due to the parameterization of the standard, with literature, it is observed that this is a low value. In general, low expansibility rates were found, because the reduction in particle size significantly reduces the potential for expansion (Machado et al, 2002). The data obtained in the analysis of the expansibility are in Figure 4.

Fig. 4. Percentage of expansion by age for each analyzed method.

2.2. Methods

To obtain the results related to the substitution of sand for the slag, the trait in volume of 1: 5 (cement: fine aggregate) was adopted, and three experimental traces (cement: fine aggregate: slag) were performed, with the substitution percentages of 10 %, 20% and 30% by volume, resulting in the traits listed in Table 2.

Table 2. Mixture proportions used in this study (in volume) Mixture proportions

Cement

Fine Aggregate Slag

Mix 1 - 0% Mix 2 - 10% Mix 3 - 20% Mix 4 - 30%

1.0 1.0 1.0 1.0

5.0 4.5 4.0 3.5

0.0 0.5 1.0 1.5

The tests were carried out, dividing as to the characterization of the aggregates, of the mortar in the fresh and uncured state. All the tests were performed according to the technical standards of the Brazilian Association of Technical Standards (ABNT). The water / cement factor was determined for each mix, measuring the diameter at three different points after the spreading of the mold until each mortar reached a consistency of 260 ± 5 mm. Also incorporated air content and fresh mass density were obtained. In relation to the determination of the tensile strength in the compression and the flexural traction, prismatic specimens (4x4x16cm) were molded, being molded based on