Title: Internal Curing Effect of Concrete Containing Colloidal Nano Silica (CNS)

Author(s): Cihang Huang

Publication: Web Session

Volume:

Issue:

Appears on pages(s):

Keywords:

DOI:

Date: 3/28/2022

Abstract:
In this study, the internal curing effect of the colloidal nano silica (CNS) was investigated. It is hypothesized that incorporating the CNS can improve the curing quality of the concrete materials by preventing the excessive loss of water. Therefore, a series of tests were designed and conducted. The water retention properties of the fresh mixtures with various dosages of CNS were firstly evaluated. Then, the internal humidity of the prepared concrete was monitored by the humidity sensors, and the drying shrinkage of the mortar sample was also recorded. A conventional internal curing agent, lightweight aggregates, was also used to compare with the CNS. The sorptivity analysis was carried out to compare the influence of the CNS on the pore structure of the concrete. The result of the experiments shows that the addition of the CNS could efficiently increase the water-holding ability of the fresh mixture, while the internal humidity of the concrete sample could be maintained at a higher level even after 28 days, which could perform better than the lightweight aggregate. The drying shrinkage of the mortar with CNS was reduced by improving the curing quality, and a finer pore structure can be expected based on the sorptivity test. The outcome of this study proves the internal curing effect of the CNS. It provides insight into the effectiveness of using CNS as an internal curing agent compared with conventional internal curing aggregates.