Effect of UV-Modified Polyamide Fibers on Mortar Workability and Superplasticizer Demand

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Özteber S., Özenç A. A., Ünverdi M., Özenç F., Eren S., Mardani A.

International Conference on Recent Innovations in Engineering and Technology (ICRIET-2026), Kowloon, Hong Kong, 9 - 10 Temmuz 2026, ss.1-4, (Tam Metin Bildiri)

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Basıldığı Şehir: Kowloon
  • Basıldığı Ülke: Hong Kong
  • Sayfa Sayıları: ss.1-4
  • Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
  • Bursa Uludağ Üniversitesi Adresli: Evet

Özet

Surface modification in fiber-reinforced cementitious composites is a widely utilized pretreatment method to enhance the fiber-matrix bonding strength. Ultraviolet (UV) irradiation stands out as a physical surface modification technique that is easy to apply and does not produce chemical waste; however, the effects of this process on fresh mortar rheology and superplasticizer requirements are not sufficiently addressed in the literature. This study aims to experimentally demonstrate how the required dose of polycarboxylate ether (PCE) changes in standard mortar mixtures containing polyamide fibers subjected to different UV exposure times (0, 5, 10, and 15 minutes). The fiber volume fraction was fixed at 0.4%, and the PCE dosage was incrementally increased until the target flow range of 185±20 mm was achieved. The results indicate that the addition of fibers increased the PCE requirement by approximately 89% compared to the fiber-free reference mixture (from 0.38% to 0.72%), and this increase became more pronounced as the UV exposure time extended. A fifteen-minute UV treatment further increased the PCE demand by 19.4% compared to the un-treated fiber group, raising it to a level of 0.86%. Although UV surface modification has the potential to enhance the interaction of polyamide fibers with the cement matrix, it increases the superplasticizer requirement in fresh mortars. Therefore, in mortar mixtures containing UV-modified polyamide fibers, the PCE dosage must be re-optimized depending on the UV exposure time to ensure the target workability.