AN INVESTIGATION ON THE MECHANICAL PROPERTIES OF STANDARD CURED ALKALI ACTIVATED MORTARS UNDER STATIC AND DYNAMIC LOADINGS

Yıl 2016, Cilt: 18 Sayı: 54, 381 - 398, 01.09.2016

Mert Yücel Yardımcı Serdar Aydın

Öz

In this study, the effects of partial replacement of ground granulated blast furnace slag (YFC) with fly ash (FA), metakaolin (MK) and silica fume (SD) and the silicate modulus of the activator solution on the compressive strength and flexural performance under static and impact loading conditions have been investigated. The reaction forces were recorded by an data acqusision system which is Test results showed that the MK incorporation influenced the mechanical properties negatively while the SD incorporation affected positively. Increasing the Ms ratio of the activator significantly improved the mechanical properties of MK incorporated mixtures. It has been shown that the flexural strength and fracture energy of standard water cured alkali activated mortars under impact loading were 2.54 – 4.89 and 14.20 – 26.93 times more than that of static loading conditions, respectively

Anahtar Kelimeler

Alkali activated cement, low-velocity impact, Ductility index

ALKALİLERLE AKTİVE EDİLMİŞ STANDARD KÜRLÜ HARÇLARIN STATİK VE DİNAMİK YÜKLEME ALTINDAKİ MEKANİK ÖZELİKLERİNİN İNCELENMESİ

Öz

Bu çalışmada, alkalilerle aktive edilmiş bağlayıcıların ana hammaddesi olan yüksek fırın cürufu (YFC) yerine uçucu kül (UK), metakaolin (MK) ve silis dumanı (SD) ikamesinin ve aktivatörün Ms oranının (SiO2/Na2O) alkalilerle aktive edilmiş standart kürlü harçların (AAH), basınç dayanımları, statik ve düşük hızlı darbe yüklemeleri altındaki eğilme performansları üzerindeki etkileri incelenmiştir. Sonuçlar, YFC yerine MK ikamesinin mekanik özellikleri olumsuz yönde, SD ikamesinin ise olumlu yönde etkilediğini göstermiştir. Ms oranındaki artış, MK ikamesi ile üretilen harçların mekanik özelliklerini önemli ölçüde geliştirmiştir. Darbe yükleri altında, standart su kürüne maruz AAH’lerin eğilme dayanımı ve kırılma enerjisinin statik yüklemedekine kıyasla sırasıyla 2,54 – 4,89 ve 14,20 – 26,93 kat daha yüksek olduğunu ortaya konmuştur

Anahtar Kelimeler

Alkalilerle aktive edilmiş bağlayıcılar, Düşük hızlı darbe, Düktilite indeksi

Kaynakça

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