Abstract In the present note, constitutive equations for air-water-solid three-phase porous materials were formulated considering thermodynamics in the context of continuum mechanics. In the formulation, the complementary energy function was used and the internal variable was adopted that manifests the inelastic strain. Then, a linear three-phase elastic model was analyzed in detail and the material parameters were identified based on drained, unjacketed tests and the suction-saturation relation. It is well known that, for partially saturated soils, Bishop’s effective stress, generalized Bishop’s effective stress and the skeleton stress concepts, etc. are used. From the present study, it was found that the skeleton stress with Biot’s coefficient can be reasonably derived for air-water-solid three-phase materials. In addition, a saturation-matric suction relation was obtained by the constitutive model that includes the interaction between the solid skeleton and the fluids.

中文翻译：

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三相多孔材料本构模型的建立与骨架应力

摘要 在本说明中，空气-水-固体三相多孔材料的本构方程在连续介质力学的背景下考虑到热力学。在公式中，使用了补充能量函数，并采用了表现非弹性应变的内部变量。然后，详细分析了线性三相弹性模型，并基于排水、无夹套试验和吸饱和度关系确定了材料参数。众所周知，对于部分饱和的土，采用Bishop有效应力、广义Bishop有效应力和骨架应力等概念。从目前的研究中发现，对于气-水-固三相材料，可以合理地推导出具有Biot系数的骨架应力。此外，