01664072

Component

Electrical resistivity measurements are being increasingly used as measurements for concrete acceptance in practice. It has been shown that these measurements are sensitive to temperature. This paper examines the influence of temperature on electrical resistivity measurements in concrete. Two commonly used approaches for temperature corrections were evaluated: a linear temperature correction approach (α) and an activation energy based temperature correction approach (Ea-cond). These approaches were compared with each other and their predictive capabilities were assessed using measured data from various concrete mixtures. It was found that for cases of low temperature sensitivity, the predictions obtained with α and with Ea-cond were very similar. However, the Ea-cond approach was found to provide more accurate corrections than corrections using α for measurements conducted at lower temperatures and for systems with higher temperature sensitivities. For saturated concrete specimens, both the linear (α) and activation energy (Ea-cond) approaches are acceptable while the use of Ea-cond approach provides better predictive capabilities in sealed concrete specimens, especially at low temperatures. Average values for Ea-cond were found to be 29.8 kJ/mol for sealed specimens and 15.8 kJ/mol for saturated specimens, and corresponding average values of α are 3.25 %/°C and 2.00 %/°C, respectively. The saturated values are closer to what may be expected of a pore solution on its own.

This paper was sponsored by TRB committee AFN20 Standing Committee on Properties of Concrete.

18-00848

English

15p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Activation (Chemistry); Admixtures; Concrete; Electrical resistivity; Energy; Linearity; Measurement; Sensitivity analysis; Service life; Temperature

Highways; Materials; I30: Materials

Transportation Research Board Annual Meeting 2018 Paper #18-00848

TRIS, TRB, ATRI

Jan 8 2018 10:12AM