THE EFFECT OF AGGREGATE MAXIMUM SIZE ON IMPACT RESISTANCE OF FIBER REINFORCED CONCRETE

In this study, the effect of maximum size of aggregate on impact resistance of fiber reinforced concrete were investigated. Using crushed limestone aggregate with 10, 15, 20 and 25 mm of maximum size, 8 different normal-steel fiber reinforced concretes were produced. Water/cement ratio and cement dosage of concrete mixtures are 0.5 and 400 kg/m3, respectively. Hooked-end bundled steel fibers with l/d ratio of 65 and 1.0% fiber volume were used in fiber concretes. After 28 days standard curing, compressive strength, split tensile strength and ultrasonic pulse velocity tests were performed on 150/150/150 mm cube specimens. Additionally, impact resistances of concrete specimens were determined using impact test apparatus described in ACI 544.3R-93. 150x300 mm cylinders were prepared for impact resistance tests. After 28 days curing, these specimens were cut and 150x64 mm special discs were prepared. Impact resistance test were performed on these special discs. Experimental results were evaluated corresponding to presence of steel fiber and aggregate maximum size

ABRASION RESISTANCE ESTIMATION OF HIGH STRENGTH CONCRETE

This study gives the results of a laboratory investigation undertaken to determine the relationship between mechanical properties (compressive and flexural strengths) and abrasion resistance of 65-85 MPa high strength concretes incorporating silica fume, fly ash and silica fume-fly ash mixtures as supplementary cementing materials. A series of six different concrete mixtures including a control high strength concrete mixture (C1), and five high strength concrete mixtures (C2, C3, C4, C5, C6) incorporating supplementary cementing materials, were manufactured. The compressive strength, flexural strength, and abrasion resistance were determined for each mixture at 28-days. Mathematical expressions were suggested to estimate the abrasion resistance of concrete regarding their compressive strength and flexural strength

YÜKSEK DAYANIMLI BETONDA AŞINMA DİRENCİNİN TAHMİNİ

Bu çalışmada, silis dumanı ve/veya uçucu kül içeren basınç dayanımı 65-85 MPa olan yüksek dayanımlı betonların, aşınma direnci ile mekanik özelikleri (basınç ve eğilme dayanımı) arasındaki ilişkiyi belirleyebilmek amacıyla yapılan deneysel çalışma sonuçları sunulmuştur. Bir adet yüksek dayanımlı beton kontrol karışımı (C1) ve beş adet katkı içeren yüksek dayanımlı beton karışımı olmak üzere (C2, C3, C4, C5, C6), toplam altı adet beton karışımı hazırlanmıştır. Tüm karışımların 28 günlük basınç dayanımları, eğilme dayanımları ve aşınma dirençleri belirlenmiştir. Betonların basınç ve eğilme dayanımına bağlı olarak aşınma direncini tahmin eden matematiksel eşitlik önerilmiştir