The development of double hardening elasto-plastic constitutive model and the systematization of geomaterial mechanics based on the model

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04408
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Geotechnical engineering
• Research Institution: Nagoya University
• Principal Investigator: Nakano Masaki 名古屋大学, 工学研究科, 教授 (00252263)
• Co-Investigator(Kenkyū-buntansha): 山田 正太郎 名古屋大学, 工学研究科, 准教授 (70346815) ; 野田 利弘 名古屋大学, 減災連携研究センター, 教授 (80262872) ; 酒井 崇之 名古屋大学, 工学研究科, 助教 (20773592)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 地盤工学 / 地盤材料力学 / 弾塑性構成式 / 材料定数

Outline of Final Research Achievements

Constitutive models for describing the mechanical behavior of soils have been separated into the models for clayey soils and ones for sandy soils. In this study, to integrate a different kind of constitutive models, a new framework in elasto-plastic theory for soils called “combined elasto-plastic constitutive model” is proposed. This framework allows the SYS Cam-clay model, which can describe the mechanical behavior of naturally deposited clayey soils, and the non-associated Drucker-Prager model, which has mainly simulated the undrained shear behavior of sandy soils, to simultaneously work within a single model.
We also implemented the developed constitutive model into a soil-water coupled finite deformation code with the inertial term. This code enabled us to simulate ground disasters such as liquefaction and evaluate the effects of several countermeasures against the disasters.

Free Research Field

地盤工学

Academic Significance and Societal Importance of the Research Achievements

地盤工学分野では，長年の間，粘土と砂の構成式は別々に扱われてきたが，これらを統合可能な数理モデルが開発されたことによって，地盤材料力学の体系化に大きな前進があった．また，同モデルを実装した水～土連成解析コードによって，地震時の液状化現象や軟弱粘土地盤の荷重載荷による変形・破壊問題など，地盤災害の予測やそれを回避するための対策効果の検討が単一の理論体系の下で実施できるようになった．