Open AccessResearch on Rebound Rate of Nano-Scale Admixture Wet-Mix Shotcrete
Author(s) -
Feng Ning,
Cai Xu Yue,
Yanqin Bai,
Jian Tong Ding,
Feng Zhang
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/678/1/012109
Subject(s) - shotcrete , materials science , fineness , rebound effect (conservation) , composite material , metallurgy , geotechnical engineering , engineering , electrical engineering , efficient energy use
High rebound rate and low construction efficiency are outstanding problems for traditional shotcrete. To solve these problems, Nano-scale admixture (NSA) was used to prepare high performance wet-mix shotcrete. Tests of sidewall rebound rate and overall rebound rate were carried out to study the effect of NSA. A total of eight mixtures were measured to assess the effect of impact factors such as active admixture variety (silica fume and NSA), NSA content (7.5%, 10% and 12.5%) and NSA fineness (128nm, 137nm and 147nm) on rebound rate. The results indicated that the sidewall rebound rate and overall rebound rate of shotcrete were reduced by 17% and 25% respectively when NSA replaced silica fume at the same content, which was about 10% with respect to the total amount of cementing materials. Rebound rate decreased as NSA content increased from 7.5% to 12.5%. Rebound rate also could be reduced when particle size of NSA deceased from 147nm to 128nm. The results confirmed the role of NSA in reducing rebound rate of shotcrete. NSA could promote the adhesion between shotcrete and receiving surface, improve the cohesion in mixtures, which could keep such as coarse aggregate, synthetic fiber from being rebounded out of cementing paste. Therefore, the rebound rate was reduced.