Effect of natural pozzolans as mineral admixture on the performance of cemented-paste backfill of sulphide-rich tailings


ERÇIKDI B. , CİHANGİR F. , KESİMAL A. , DEVECİ H. , ALP İ.

WASTE MANAGEMENT & RESEARCH, cilt.28, sa.5, ss.430-435, 2010 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 28 Konu: 5
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1177/0734242x09351905
  • Dergi Adı: WASTE MANAGEMENT & RESEARCH
  • Sayfa Sayıları: ss.430-435

Özet

This paper presents the effect of the natural pozzolans as mineral additives on the short- and long-term strength and stability performance of cemented paste backfill (CPB) samples. Prior to their use in CPB studies, the natural pozzolans - the volcanic tuffs (Akkus Trass [AT] and Fatsa Trass [FT]) and pumice (KP) - were tested for their pozzolanic characteristics. These tests revealed that the pozzolanic activity of the natural pozzolans is closely inter-related with their content of reactive silica and, accordingly, KP has the highest pozzolanic activity. The addition, or increasing the amount, of natural pozzolans in the binder phase resulted in a slower rate of strength development of CPB samples. The deterioration in stability of CPB samples prepared from Portland cement (PC) alone (i.e. a strength loss of 24.6%) occurred following 56 days. The replacement of PC with FT and AT led to even higher losses in strength. However, the addition of KP (up to 30 wt%) mitigated, to a certain extent, long-term strength and stability problems with the losses in strength of CPB samples consistently lower than 20%. It can be inferred that the performance of the natural pozzolans as a mineral additive in CPB is dependent intimately on their pozzolanic characteristics.