PSI - Issue 64

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Rawan Ramadan et al. / Procedia Structural Integrity 64 (2024) 1927–1934 Author name / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 3. Effect of adding different percentages of PA fibers on the DR-SH of cement paste at 45°C.

3.2. Autogenous shrinkage (AUTO-SH) The same trend as DR-SH is observed in Fig. 4. With an increase in the percentage of PA fibers, there is a concurrent decrease in AUTO-SH. The most significant reduction occurs when 2% PA fibers are incorporated, showing an 18.9% decrease compared to the control mix. This decline is primarily attributable to the moisture-retaining properties of PA fibers within the matrix, which contribute to reducing AUTO-SH, mainly associated with moisture release. Moreover, in the first stage, PA fibers absorb water during the hydration process and subsequently release it into the matrix during a later period (Saradar et al. 2018; Kouta et al. 2020).

Fig. 4. Effect of adding different percentages of PA fibers on the AUTO-SH of cement paste at 45°C.