Electric conductivity, piezoresistivity and piezoconductivity of orthotropi
c materials are studied theoretically on the basis of electrostatic theory
and the classical thin laminate theory. The correlation between piezoresist
ivity and piezoconductivity in the Cauchy strain is derived. Finally, a lam
inate theory of piezoconductivity for a composite laminate under a state of
plane stress is put forward. (C) 1999 Elsevier Science Ltd. All rights res
erved.