Title:
Volume Electrical Resistivity of Carbon Fiber Cement Composites
Author(s):
Farhad Reza, Gordon B. Batson, Jerry A. Yamamuro, and Jong S. Lee
Publication:
Materials Journal
Volume:
98
Issue:
1
Appears on pages(s):
25-35
Keywords:
cement; fiber-reinforced concrete; test
DOI:
10.14359/10157
Date:
1/1/2001
Abstract:
The results of some fundamental investigations on the bulk electrical properties of carbon fiber cement composites (CFCCs) are presented with the prospect of developing a new nondestructive testing method to assess the integrity of the composite. The addition of carbon fibers to portland cement-based concrete or mortar improves the structural performance and at the same time significantly decreases the bulk electrical resistivity. This makes CFCC responsive to interrogation by electrical methods. Three different electrode configurations were investigated for their applicability in measuring electrical resistivity of CFCC specimens. The volume electrical resistivity of CFCC specimens was recorded as a function of curing time. The dependence of this electrical resistivity on the water-cement ratio (w/c), sand-cement ratio, volume fraction of carbon fibers in the mixture, and the length of fibers was determined. The reliability of measurements performed using both DC and AC was evaluated. The relationships between resistivity and both temperature and relative humidity were also investigated.