01594629

Component

A rapid concrete cylinder test (RCCT) has been developed to assess alkali silica reactivity of aggregates in concrete. In RCCT method, a cylindrical concrete specimen (3 by 6 inches) is immersed in a soak solution of equal chemistry with pore solution (leach-proof condition) and the length change measured through LVDT and data acquisition system at 60°C. The automatic data collection system under constant temperature and leach-proof condition enhance reliability of the RCCT method. Cylinders made with highly reactive borosilicate glass balls were tested first to validate the proposed method as a proof of concept. Concrete mixes made of aggregates with varying degree of reactivity were tested by the RCCT at multiple levels of alkalinity (i.e., 3.0, 4.5, 6.7, and 8.9 lb/yard3 10 ). A favorable comparison between the RCCT and ASTM C 1293 has been observed. RCCT with relatively low alkali loading (e.g., 4.5 lb/yard3 11 ) as opposed to high alkali loadings (i.e., 6.7–8.9 lb/yard3 12 ) in the current ASTM C 1293 method can effectively be used to pass/fail a concrete mix in a relatively short time (i.e., 28 days). The usefulness of the RCCT method to determine optimum fly ash content to control ASR has also been attempted. Although the data is limited at this time, RCCT method has shown promises to do fly ash optimization in order to develop safe ASR-resistant mixes. The RCCT has the ability to emerge as a potential method to test job mix and work is under progress to explore this possibility

This paper was sponsored by TRB committee AFN30 Standing Committee on Durability of Concrete.

01584066

16-6171

English

18p

2016

Transportation Research Board 95th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Alkali silica reactions; Concrete; Cylinders (Geometry); Silica

Highways; Materials

Transportation Research Board Annual Meeting 2016 Paper #16-6171

TRIS, TRB, ATRI

Jan 12 2016 6:43PM