Title: Fiber-Reinforced Cement for Piezoelectricity and Pyroelectricity

Author(s): S. Wen and D. D. L. Chung

Publication: Symposium Paper

Volume: 216

Issue:

Appears on pages(s): 115-128

Keywords: cement; concrete; dielectric; fiber; piezoelectric; pyroelectric; sensing; thermoelectric

DOI: 10.14359/12895

Date: 10/1/2003

Abstract:
Fiber-reinforced cement for piezoelectricity and pyroelectricity is introduced, as these phenomena are useful for the sensing of strain and temperature. The use of short steel fibers (8 µm diameter), together with polyvinyl alcohol, as admixtures greatly enhances these effects, thereby attaining longitudinal piezoelectric coupling coefficient 3 x 10-" mN (10kHz), and pyroelectric coefficient 6 x 10$ C/mz.K (10 kHz). The piezoelectric effect is comparable in magnitude to that of PZT. However, due to the high value (2,500) of the relative dielectric constant, the piezoelectric voltage coefficient and pyroelectric voltage are comparable to or even lower than those of plain cement paste or carbon fiber (15 µm diameter) cement paste. Carbon fiber cement paste and plain cement paste are comparable in the piezoelectric coupling coefficient, piezoelectric voltage coefficient and pyroelectric voltage, though the pyroelectric coefficient is higher for carbon fiber cement paste than plain cement paste.