Evaluation of the neutralization performances of the industrial waste products (IWPs) in sulphide-rich environment of cemented paste backfill.

The purpose of this research is to examine the neutralization performances of CaO-rich industrial waste products (IWPs) in the sulphide-rich environment of cemented paste backfill (CPB). A total of 205 CPB samples were prepared by using four different IWPs (type-C fly ash (C-FA), blast furnace slag (BFS), calcitic limestone (CL) and dolomitic limestone (DL)) as 5, 10 and 15 wt% substitute for sulphide-rich tailings. These CPB samples were cured and subjected to the acid (pH) and sulphate (SO) tests during 7-360 days of curing periods.

Utilisation of construction and demolition waste as cemented paste backfill material for underground mine openings.

This study presents the utilisation of finely ground construction and demolition waste (CDW) as partial replacement (5-15 wt.%) to sulphide tailings on the short- and long-term strength, durability (i.e.

Core size effect on the dry and saturated ultrasonic pulse velocity of limestone samples.

This study presents the effect of core length on the saturated (UPVsat) and dry (UPVdry) P-wave velocities of four different biomicritic limestone samples, namely light grey (BL-LG), dark grey (BL-DG), reddish (BL-R) and yellow (BL-Y), using core samples having different lengths (25-125mm) at a constant diameter (54.7mm). The saturated P-wave velocity (UPVsat) of all core samples generally decreased with increasing the sample length.

Assessment of strength properties of cemented paste backfill by ultrasonic pulse velocity test.

Ultrasonic pulse velocity (UPV) test is one of the most popular non-destructive techniques used in the assessment of the mechanical properties of concrete or rock materials. In this study, the effects of binder type/dosage, water to cement ratio (w/c) and fines content (<20 μm) of the tailings on ultrasonic pulse velocity (UPV) of cemented paste backfill (CPB) samples were investigated and correlated with the corresponding unconfined compressive strength (UCS) data. A total of 96 CPB samples prepared at different mixture properties were subjected to the UPV and UCS tests at 7, 14, 28 and 56-days of curing periods.

Strength and ultrasonic properties of cemented paste backfill.

This paper presents the strength (UCS) and ultrasonic pulse velocity (UPV) properties of cemented paste backfill (CPB) produced from two different mill tailings (Tailings T1 and T2). A total of 240 CPB samples with diameter×height of 5 × 10 cm and 10 × 20 cm prepared at different binder dosages (5-7 wt.%) and water-to-cement ratios (3.

Effect of desliming of sulphide-rich mill tailings on the long-term strength of cemented paste backfill.

This paper presents the effect of desliming on the short- and long-term strength, stability and rheological properties of cemented paste backfill (CPB) produced from two different mill tailings. A 28-day unconfined compressive strength (UCS) of ≥1.0 MPa and the maintenance of stability over 224 days of curing were selected as the design criteria for the evaluation of paste backfill performance.

Utilization of water-reducing admixtures in cemented paste backfill of sulphide-rich mill tailings.

This study presents the effect of three different water-reducing admixtures (WRAs) on the rheological and mechanical properties of cemented paste backfill (CPB) samples. A 28-day strength of > or = 0.7 MPa and the maintenance of the stability (i.

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

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.

Utilization of industrial waste products as pozzolanic material in cemented paste backfill of high sulphide mill tailings.

In this study, the potential use of the industrial waste products including waste glass (WG), fly ash (FA), granulated blast furnace slag (GBFS) and silica fume (SF) as pozzolanic additive for the partial replacement of ordinary Portland cement (OPC) in cemented paste backfill (CPB) of sulphide-rich mill tailings was investigated. The influence of these industrial waste products on the short- and long-term mechanical performance of CPB was demonstrated. The rate of development of strength of CPB samples tended to slow down when the pozzolanic wastes were incorporated or increased in dosage in the binder phase.