Multiscale modeling of the effective elastic properties of fluid-filled porous materials

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:162

Article

Liu, Mingchao^1,2,3  Wu, Jian^1,2  Gan, Yixiang³  Hanaor, Dorian A. H.⁴  Chen, C. Q.^1,2 

[1] Tsinghua Univ, Dept Engn Mech, CNMM, Beijing 100084, Peoples R China

[2] Tsinghua Univ, AML, Beijing 100084, Peoples R China

[3] Univ Sydney, Sch Civil Engn, Sydney, NSW 2006, Australia

[4] Tech Univ Berlin, Inst Mat Sci & Technol, D-10623 Berlin, Germany

关键词: Porous materials;    Effective elastic properties;    Micromechanical model;    Double- porosity;    Fluid diffusion;   

DOI  :  10.1016/j.ijsolstr.2018.11.028

来源: Elsevier

【 摘 要 】

Fluid-filled porous materials are widely encountered in natural and artificial systems. A comprehensive understanding of the elastic behavior of such materials and its dependence on fluid diffusion is therefore of fundamental importance. In this work, a multiscale framework is developed to model the overall elastic response of fluid-filled porous materials. By utilizing a two-dimensional micromechanical model with porosity at two scales, the effects of fluid diffusion and the geometric arrangement of pores on the evolution of effective properties in fluid-filled porous materials are investigated. Initially, for a single-porosity model the effective elastic properties of the dry and fluid-filled porous materials with ordered pores are obtained theoretically by considering a geometrical factor, which is related to the distribution of pores in the matrix. Model predictions are validated by finite element simulations. By employing a double-porosity model, fluid diffusion from macro- to micro-scale pores driven by a pressure gradient is investigated, and the resulting time-dependent effective elastic properties are obtained for both constant pressure and constant injection rate conditions. It is found that the presence and diffusion of pressurized pore fluid significantly affect the elastic response of porous materials, and this must be considered when modeling such materials. It is expected that the proposed theoretical model will advance the understanding of the fluid-governed elastic response of porous materials with implications towards the analysis of geophysical, biological and artificial fluid-filled porous systems. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

Free