Karma lifli kendiliğinden yerleşen hafif betonun taze ve sertleşmiş özellikleri üzerinde lif hacminin ve mikro lif tipinin etkisi
Küçük Resim Yok
Tarih
2025
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
İnönü Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
İnovatif çimento esaslı bir kompozit olan kendiliğinden yerleşen betonun (KYB), özellikle pomza kaynakları bakımından zengin olan ülkemizde hafif ağırlıklı bir beton olarak üretilmesinin avantajlı olacağı açıktır. Ayrıca gevrek bir malzeme olan betonun çekme dayanımının iyileştirilmesi amacıyla betona çelik lifler eklenmesi son zamanlarda sıklıkla çalışılan konulardandır. Bu tez çalışması kapsamında, hibrit lifli kendiliğinden yerleşen hafif beton (KYHB) tasarlanması ve bu inovatif betonun taze ve sertleşmiş özelliklerinin incelenmesi planlanmaktadır. Bu amaçla, çelik lif ile birlikte polipropilen (PP) ve poli-vinil alkol (PVA) liflerin KYHB karışımlarına hacimce farklı oranlarda (%1.25, %1, %0.75) ve farklı kombinasyonlarda ilave edildiği hibrit lif takviyeli KYHB karışımları ile lifsiz kontrol numunesi dahil toplamda 13 adet karışım tasarlanmıştır. Deneysel çalışmada, lif hacmi, lif tipi ve lif kombinasyonu değişken parametre olarak esas alınmış ve karışımların taze (birim hacim ağırlık,çökme-yayılma, T500 ve J-halkası) ve sertleşmiş beton (basınç dayanımı, yarmada çekme dayanımı, eğilmede çekme dayanımı, elastisite modülü ve kılcal su emme) özellikleri araştırılmıştır. Sonuç olarak, hacimce lif miktarı ve lif kombinasyonu artmasının işlenebilirliği olumsuz etkilemesinin yanında, karışımlara eklenen sentetik lif miktarının hacimce artması ile numunelerin basınç dayanımlarının arttığı görülürken, PP içeren KYHB numunelerin elastisite modülü değerlerinin PVA içeren numunelerinkine göre daha düşük olduğu tespit edilmiştir. Ayrıca, karışımlardaki toplamda hacimce lif oranı ve lif kombinasyonları (ikili ve üçlü hibrit) arttıkça yarmada çekme dayanımının olumlu yönde etkilendiği ve tokluk değeri yüksek olan lifli KYHB numunelerinin daha belirgin çoklu çatlak davranışı sergilediği gözlemlenmiştir. Bütün bunlara ilaveten, PVA lifli KYHB numunelerinin kılcal su emme katsayılarının PP lif takviyesi içeren numunelerinkine kıyasla daha fazla olduğu görülmüştür.
It is clear that it would be advantageous to produce self-compacting concrete (SCC), an innovative cement-based composite, as a lightweight concrete, especially in our country, which has a rich pumice resources. Moreover, adding steel fibers to concrete in order to improve the tensile strength of concrete, which is a brittle material, has been frequently studied recently. Within the scope of this thesis study, it is planned to design hybrid fiber self-compacting lightweight concrete (SCLC) and examine the fresh and hardened properties of this innovative concrete. For this purpose, hybrid fiber-reinforced SCLC mixtures including polypropylene (PP) and poly-vinyl alcohol (PVA) fibers together steel fibers at different volume ratios (1.25%, 1%, 0.75%) and different combinations (binary, ternary) as well as Control sample without fiber were designed at a total of 13. In experimental study, fiber volume, fiber type and fiber combination were taken as variable parameters and the properties of fresh (unit weight, slump-sprawl, T500 and J-ring) and hardened concrete (compressive strength, splitting tensile strength, flexural tensile strength, modulus of elasticity and capillary water absorption) of the mixtures were investigated. In conclusion, it was found that the increase in the amount of fiber by volume and fiber combination negatively affected the workability, and the compressive strength of the samples increased with the increase in the amount of synthetic fiber added to the mixtures by volume. The elasticity modulus values of the SCLC samples containing PP were lower than those of the samples containing PVA. In addition, it was observed that as the total volumetric fiber ratio and fiber combinations (binary and ternary hybrid) in the mixtures increased, the splitting tensile strength was positively affected and fiber reinforced SCLC samples with high toughness values exhibited more pronounced multiple crack behavior. In addition to all these, it was observed that the capillary water absorption coefficients of SCLC samples with PVA fiber were higher than those of the samples containing PP fiber reinforcement.
It is clear that it would be advantageous to produce self-compacting concrete (SCC), an innovative cement-based composite, as a lightweight concrete, especially in our country, which has a rich pumice resources. Moreover, adding steel fibers to concrete in order to improve the tensile strength of concrete, which is a brittle material, has been frequently studied recently. Within the scope of this thesis study, it is planned to design hybrid fiber self-compacting lightweight concrete (SCLC) and examine the fresh and hardened properties of this innovative concrete. For this purpose, hybrid fiber-reinforced SCLC mixtures including polypropylene (PP) and poly-vinyl alcohol (PVA) fibers together steel fibers at different volume ratios (1.25%, 1%, 0.75%) and different combinations (binary, ternary) as well as Control sample without fiber were designed at a total of 13. In experimental study, fiber volume, fiber type and fiber combination were taken as variable parameters and the properties of fresh (unit weight, slump-sprawl, T500 and J-ring) and hardened concrete (compressive strength, splitting tensile strength, flexural tensile strength, modulus of elasticity and capillary water absorption) of the mixtures were investigated. In conclusion, it was found that the increase in the amount of fiber by volume and fiber combination negatively affected the workability, and the compressive strength of the samples increased with the increase in the amount of synthetic fiber added to the mixtures by volume. The elasticity modulus values of the SCLC samples containing PP were lower than those of the samples containing PVA. In addition, it was observed that as the total volumetric fiber ratio and fiber combinations (binary and ternary hybrid) in the mixtures increased, the splitting tensile strength was positively affected and fiber reinforced SCLC samples with high toughness values exhibited more pronounced multiple crack behavior. In addition to all these, it was observed that the capillary water absorption coefficients of SCLC samples with PVA fiber were higher than those of the samples containing PP fiber reinforcement.
Açıklama
Anahtar Kelimeler
İnşaat Mühendisliği, Civil Engineering
