کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1455514 989049 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Cemented paste backfill of sulphide-rich tailings: Importance of binder type and dosage
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی صنعتی و تولید
پیش نمایش صفحه اول مقاله
Cemented paste backfill of sulphide-rich tailings: Importance of binder type and dosage
چکیده انگلیسی

In this study, the influence of binder type and dosage on the mechanical properties and microstructure of cemented paste backfill (CPB) was investigated using ordinary Portland cement (OPC), Portland composite cement (PCC) and sulphate resistant cement (SRC). The CPB samples of OPC and PCC were observed to lose their unconfined compressive strengths (UCSs) after 56 days. This could be associated with the sulphide moiety of the tailings, i.e. the attack on hydration products by sulphate and acid internally generated via the oxidation of pyrite present. In this respect, those CPB samples of sulphate resistant-based cements (SRC and a mix of OPC and SRC) maintained good long-term strengths and stability (i.e. no loss of strength). Increasing binder dosage (5–7 wt.%) improved the UCSs of CPB samples up to 1.9-fold with no loss of strength at >5 wt.%. Decreasing water-to-cement ratio appeared to produce a beneficial effect on the UCSs of CPB samples. SEM studies have provided further insight into the microstucture of CPB and confirmed the deleterious formation of gypsum as the expansive phase. These findings have demonstrated the practical importance of binder type/dosage and water-to-cement ratio for the short- and long-term mechanical performance of CPB.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cement and Concrete Composites - Volume 31, Issue 4, April 2009, Pages 268–274
نویسندگان
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