Residual compressive strength of fire-damaged mortar after post-fire-air-curing


Karahan O.

FIRE AND MATERIALS, cilt.35, ss.561-567, 2011 (SCI İndekslerine Giren Dergi)

  • Cilt numarası: 35 Konu: 8
  • Basım Tarihi: 2011
  • Doi Numarası: 10.1002/fam.1074
  • Dergi Adı: FIRE AND MATERIALS
  • Sayfa Sayısı: ss.561-567

Özet

The effects of cooling regimes and post-fire-air-curing on compressive strength of mortar were investigated. Mortars were made with CEN reference sand, CEM I 42.5R cement and natural spring water. The sandcement and watercement materials' ratios were chosen as 3.0 and 0.50 for all mixtures, respectively. At 28 days, the specimens were heated to maximum temperatures of 400, 600, 800 and 1000 degrees C. Specimens were then allowed to cool in the air, furnace and water. After cooling, the specimens were air-recured. Compressive strength test was carried out before air-recuring and after 7 days of air-recuring. The highest reduction in compressive strength was observed at 1000 degrees C regardless of cooling regime. Gradual cooling regime in air and furnace without post curing showed almost no difference in terms of compressive strength reduction for four elevated temperatures. Shock cooling in water caused significant reduction in compressive strength compared with both gradual cooling regimes without post curing. After air and furnace cooling regimes, 7 days air-recured specimens showed further reduction in compressive strength for four elevated temperatures. Specimens cooled in water and subjected to 7 days air-recuring showed significant strength gain approximately 39, 100 and 130% for 400, 600 and 800 degrees C elevated temperature, respectively. Copyright (C) 2010 John Wiley & Sons, Ltd.