AUTHOR=Deqing Gan , Hongbao Li , Chao Chen , Hongjian Lu , Youzhi Zhang 

TITLE=An Experimental Study on Strength Characteristics and Hydration Mechanism of Cemented Ultra-Fine Tailings Backfill

JOURNAL=Frontiers in Materials

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2021.723878

DOI=10.3389/fmats.2021.723878

ISSN=2296-8016

ABSTRACT=In order to study the strength characteristics and hydration mechanism of the cemented ultra-fine tailings backfill (CUTB), the uniaxial compressive strength (UCS) test of CUTB and cemented classified tailings backfill (CCTB) with cement-tailing ratio (C/T ratio) of 1:4 and 1:6 and curing ages of 3d, 7d,14d and 28d were carried out. The hydration products and morphology of the cemented paste backfill (CPB) were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results show that: the UCS of the CUTB is significantly than the CCTB in the same conditions, the greater C/T ratio and curing age, the greater of UCS difference value. The UCS growth curve of the CUTB is approximately S-shape, and there is a relationship between the UCS and curing age. The ultra-fine tailings particles in the CUTB have potential activity, in the alkaline environment generated cement hydration, active SiO2 and Al2O3 particles undergo secondary hydration reaction, resulting in the CUTB is no or very little Ca(OH)2 crystals be generated, and the hydration products and morphology are also different.