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Research Article: Tawashi & AlAmoudi 65

Table 2. SCC fresh properties:
Cement
J-ring
Mixture quantity W/C Superplasticizer Slump Flow (sec) (DJ %) Segregation Test

(%)
SF (cm)
(SR%)

( kg/m 3 )
SCC-HRW-550 550 0.39 2.0 58 5.40 86 6.42
SCC-HRW-500 500 0.39 2.5 52 4.86 96 4.06
SCC-HRW-450 450 0.39 2.5 - - - -
Allowed 55-65 - ≥80% ≤15%
plasticizer by reducing the ratio W/C up to 13%.
Strength of SCC Samples on the Uni-Axial Thus, there is an improvement in the SCC
Compression concrete in terms of strength and strain
The laboratory tests result of SCC cylindrical behavior. Figure 4.
samples produced locally at uni-axial
compression [14] show the contribution of the

Fig. 4. Fracture Test of SCC Cylindrical Samples

According to laboratory tests, an increase in the This can be explained by the change in the
strength of concrete containing plasticizer HRW molecular structure of SCC mixtures when the
(high reduction water) by 2% of the cement ratio W/C is stable. So, it is better to use a higher
weight up to 12% has been noted, compared to quantity of cement for a lower plasticizer
the reference sample, which has the same percentage, and stability by a ratio of W/C.
proportions of materials but without a Since the concrete molecular structure is made
plasticizer. The plasticizer in all concrete up of two components, aggregates and paste.
mixtures contributed to an increase in the Aggregates are generally classified into two
operability and a decrease in the W/C ratio. The groups, fine and coarse, and occupy about 70%
percentage up in the strength was due to the of the mix volume. The paste is composed of
quantity of cement used, the type of plasticizer, cement, water, and entrained air and ordinarily
the percentage of plasticizer, and the W/C ratio constitutes 30% of the remaining volume.
[15] . The decrease in the compression strength The major change in the molecular structure of
was observed by using a lower quantity of the mixture under the influence of the
cement with a higher percentage of plasticizer. superplasticizer is on the cement paste, which

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