Acoustic nonlinearity of solids with partially liquid-filled cracks

A mechanism of the acoustic nonlinearity of solids with cracks partially fi lled with liquid is proposed. The mechanism is associated with the nonlinea r dependence of capillary pressure in liquid on the distance between the cr ack surfaces. For the aforementioned media, the nonlinear equation of state is obtained, and Young's modulus, Poisson's ratio, and the quadratic nonli nearity parameter are determined. It is shown that the presence of liquid i n cracks may lead to a substantial increase in the acoustic nonlinearity of such media, while the corresponding decrease in both Young's modulus and P oisson's ratio should be fairly small.