Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime

Details Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime

2006-01-06

arxiv.org/abs/cond-mat/0601120v1

Physics

Condensed Matter

Materials Science

14 pages, 15 figures

Scientific paper

Members of a wide class of geomaterials are known to display complex and fascinating nonlinear and nonequilibrium dynamical behaviors over a wide range of bulk strains, down to surprisingly low values, e.g., 10^{-7}. In this paper we investigate two sandstones, Berea and Fontainebleau, and characterize their behavior under the influence of very small external forces via carefully controlled resonant bar experiments. By reducing environmental effects due to temperature and humidity variations, we are able to systematically and reproducibly study dynamical behavior at strains as low as 10^{-9}. Our study establishes the existence of two strain thresholds, the first, epsilon_L, below which the material is essentially linear, and the second, epsilon_M, below which the material is nonlinear but where quasiequilibrium thermodynamics still applies as evidenced by the success of Landau theory and a simple macroscopic description based on the Duffing oscillator. At strains above epsilon_M the behavior becomes truly nonequilibrium -- as demonstrated by the existence of material conditioning -- and Landau theory no longer applies. The main focus of this paper is the study of the region below the second threshold, but we also comment on how our work clarifies and resolves previous experimental conflicts, as well as suggest new directions of research.

Affiliated with

Also associated with

No associations

Rating

Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-110828