Highly Nonlinear Solitary Waves to Estimate Orientation and Degree of Anisotropy in Rocks

This paper delves into the use of highly nonlinear solitary waves for the nondestructive identification and characterization of anisotropy in rocks. The nondestructive testing approach proposed expands upon a technique developed recently by some of the authors for the nondestructive characterization of engineering materials and structures. The technique uses the characteristics of solitary waves propagating in a periodic array of spherical particles in contact with the rock to be characterized. The features of the waves that bounce off the chain rock interface are used to infer some properties of the geomaterial under consideration. Numerical models and experimental validation were conducted to explore the feasibility of the method and to standardize the methodology for future widespread applications.

Coupling mechanism of highly nonlinear solitary waves with damaged composite material plates

The coupling interaction between nonlinear solitary waves in one-dimensional granular chains and damaged composite material plates is considered. Based on Hertz contact law and meso-mechanical model of stiffness reduction of composite material plates when the fiber breakage is the main damage mode, the coupled differential equations of particle chains and damaged composite material plates are derived. By solving the differential equations with Runge–Kutta method to get the velocity and displacement curves of particles and analyzing the delays and amplitude ratios of reflected waves, it is found that the damage quantity, fiber volume fraction, and thickness of damaged composite material plates as well as gravity have an effect on solitary waves. The preliminary research results provide a theoretical basis for nondestructive testing of damaged composite material plates by using solitary waves.