Beyza FURTANA, Erkut YALÇIN, Baha Vural KÖK, Mehmet YILMAZ

EVA Bazlı Reçine Modifikasyonun Reolojik Özellikler Bakımından SBS Modifikasyonunu ile Karşılaştırılması

Esnek üstyapıların en üst tabakasında kullanılan ve en çok gerilmeye maruz kalan aşınma tabakası artan trafik miktarı ve yüklerinden ötürü çoğunlukla modifiye bağlayıcılarla imal edilmektedir. Aşınma tabakasının polimer tipi katkı maddeleriyle modifiye edilmesi kaçınılmaz bir durum haline gelmiştir. Son zamanlarda bitümlü karışım içinde kullanılan bitüm stiren-butadien-stiren (SBS) polimeri ile modifiye edilmektedir. Bu konuda oldukça başarılı uygulamalar söz konusudur. Ancak SBS’ye olan talep her zaman temin edilebilmesini zorlaştırmakta ve alternatif katkı maddelerinin kullanımını gündeme getirmektedir. Bu çalışmada etilen-vinil-asetat (EVA) bazlı reçinenin (EBR) bitümlü bağlayıcının reolojik özelliklerine olan etkisi araştırılmış ve SBS modifikasyonu ile karşılaştırılmıştır. Sonuçta tekerlek izi ve kohezyon özellikleri bakımından %4 EBR modifikasyonunun %3 SBS modifikasyonu ile benzer performans sergilediği, düşük ve yüksek sıcaklık özelliklerinin birlikte değerlendirilmesi durumunda ise %4,7 EBR modifikasyonunun %3 SBS modifikasyonnu ile benzer performansa sahip olduğu tespit edilmiştir.

Anahtar Kelimeler:

SBS, EVA Bazlı Reçine, Modifikasyon, Reolojik Özellikler

New Experimental Approaches to Sand Hardening by Microbial Biocalcification

In recent years there has been a rapid growth in the construction sector in order to meet the need for housing with the increase in population. This growth led to the rapid development of the cement industry. In the process of increasing industrialization, biotechnological processes are becoming more important. The most important alternative of the cement industry is the microbial bio-calcification processes. In this process, cement-like structures are produced by bacteria at room temperature conditions. Microbial bio-calcification processes have attracted the interest of researchers especially in the process of self-healing in recent years as an alternative and nature-friendly solution to the cement processes that are being produced at high temperatures. This study presents a comparative study for sand hardening by microbial bio-calcification process. Different production surfaces was used for sand hardening with Sporosarcina pasteurii such as agar plates, filter paper and polyurethane support materials. The effect of different CaCl2 concentrations (25 mM, 50 mM and 100 mM) and sand thickness (1mm, 5mm and 10 mm) was also tested. CaCO3 was determined by FTIR and measured by chemical analysis. In addition, the hardness and integrity of the samples were observed. Agar and polyurethane support materials were found to be more effective in terms of support material for sand hardening. Increased thickness reduced the hardness and 50 mM CaCl2 concentration was found to be optimum for these types of processes. This study shows the effects of sand hardness on innovative, environmentally friendly and biotechnological approach optimization.

Keywords:

Bio-calcification Bio-cement, Agar, Polyurethane, Filter paper,

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