The effect of animal and synthetic fibers on the physico-mechanical durability and microstructure properties of natural hydraulic lime-based mortars

Demircan R. K., Tayeh B. A., ÇELİK D. N., KAPLAN G., Tobbala D. E.

Materials Today Communications, cilt.35, 2023 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 35
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1016/j.mtcomm.2023.106041
  • Dergi Adı: Materials Today Communications
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
  • Anahtar Kelimeler: Durability, Horsehair fiber, NHL mortar, Salt crystallization, Synthetic fiber
  • Gazi Üniversitesi Adresli: Evet

Özet

This paper aims to study the effect of adding horsehair (HH), polypropylene (PF), carbon (CF), basalt (BF) and glass fibers (GF) on the physico-mechanical durability and microstructure properties of natural hydraulic lime-based mortars (NHL). The studied fibers were added to the mixture at 0.3 %, 0.6 %, and 1.2 % by weight of NHL and compared with plain NHL mortar. The workability (flow diameter test), physical (dry bulk density and water absorption), compressive strength (fc) and flexural strength (ff) (at 7 and 28 days) were tested. The durability was tested by water penetration depth (Wd), NaCl and Na2SO4 salt crystallization and exposure to the wetting-drying (W-D) cycles in Na2SO4, as proved by XRD. Scanning electron microscopy (SEM) of samples after 28 days of curing. From the results, it can be concluded that HH3 (0.3 % fiber) has the highest dry density (1794 kg/m3), fc and ff at 28-days (13.3 and 4.2 MPa), and resistance of all salt crystallization tested, smallest water absorption percentage (16.2 %), and water penetration depth (38.23 mm) of all mortars. On the other hand, it can be noted that adding synthetic types of fibers reduced the dry density and increased water absorption. The XRD explained that immersion or exposure to (W-D) cycles of Na2SO4 has a worse effect on hydration than NaCl exposure. The SEM shows that fiber-filled lime mortar's mechanical properties and durability are improved through the conductive network, especially HH, which had a large diameter with a rough surface and indicated a sufficient level of adhesion with the matrix.