This is a review of the papers written by the author with co-researchers, which have been published in Soils & Foundations and related publications. The contents of the papers are related to experimental and theoretical aspects of geomechanics, namely, the constitutive modeling of cohesive and sandy soils, the governing equations of three-phase materials, and analyses of the behavior of geomaterials and grounds. The following topics are included in the papers: effective stress, skeleton stress, constitutive models of clayey and sandy soils and soft rocks, material instability, strain localization, consolidation, bearing capacity, excavation problems, governing equations of multi-phase geomaterials, liquefaction, unsaturated soil, seepage-deformation coupled analysis, gas hydrate-contained soil, internal erosion, the material point method (MPM), and X-ray CT for geomaterials.(c) 2023 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Society. This is an open access article under the CC BY -NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).