Interpretation of osmotic consolidation phenomena through local measurements of displacement and cation concentration
Swelling clays such as bentonite are layered minerals composed of negatively charged clay crystals. Cations in the pore water are attracted to the negatively charged mineral crystals. The difference in ionic concentration between the crystals (inside the interlayer) and the pore water generates osmotic pressure, which causes water to move between the crystal layers and […]
Receiving a prize "Kakehashi-sho by the selection committee of Tanaka prize"
I received the "Tanaka Award Selection Committee Kakehashi Prize" from the Japan Society of Civil Engineers in recognition of the content of my lectures on Applied Project IV, which I taught during my tenure at the University of Tokyo.（https://committees.jsce.or.jp/tanaka_sho/node/70）I was very deeply moved by the opportunity to be involved in the conception of the lecture. […]
The 6th Workshop on "Bentonite"at Waseda Univ.
On January 20, I attended the 6th Bentonite Study Group held at Waseda University. I found myself discussing for four hours straight in a group where we could discuss for the pursuit of truth without hesitation. It was a very meaningful time, as we found new insights and issues.
Attending a debriefing meeting of Prof Zhang's laboratory
I participated in the interim presentation of the thesis of the Graduate School of Nagoya Institute of Technology's Geotechnical Engineering Group in the Zhang Laboratory.It was the first time in a long time that I had a stimulating time listening to the presentations of other laboratories. I may have made a little bit of an […]
New laboratory members!!
Three undergraduate students have been assigned to our lab. They are the opening members!We believe that there is some kind of fate in being assigned to a laboratory. We hope to learn and absorb a lot of things and enjoy our research activities together.The first hybrid seminar was held today. Unfortunately, due to poor arrangements […]
Workshop on "Bentonite"at Waseda Univ. & Experiment at UTokyo
On October 13, I attended a bentonite study group at Waseda University. Young researchers? The discussion among young researchers is heated and stimulating! I would like to do my research well and provide good information. The next day, October 14, I will be conducting experiments at the Soils and Geotechnical Laboratory of the University of […]
Constitutive modeling of expansive soils considering the surface phenomena of mineral crystals
Swelling clays are widely found throughout the world, and are also widely distributed in Japan, mainly in strata from the Neogene period onward. On the other hand, bentonite, a typical swelling clay, is a candidate buffer material for radioactive waste disposal facilities. However, swelling clays are considered as special soils for which no design method […]
Ice-water-soil coupled mixture theory and Isogeometric FEM
When water in the ground transforms into ice, force equilibrium, conservation of mass, and conservation of energy with consideration of latent heat exist for the three phases of soil, water, and ice, and there are interactions among them. In this study, the governing equations for such a soil-water-ice three-phase mixture are formulated. The above mixture […]
Elastoplastic constitutive model for unsaturated soils
Surface tension acts at the interface between water and air. The surface tension attracts soil particles in unsaturated soil, making the soil stronger and stiffer.In order to consider the effect of surface tension (suction) on deformation strength characteristics, this study proposes an elastoplastic model in which the normal consolidation line, which defines the soil existence […]
Modified stress considering the fabric of soil particles and the elastoplastic constitutive model
As an aggregate of particles, soil changes its particle structure as a result of stress history. Even if the stress state and density are the same, the soil exhibits various behaviors depending on the differences in particle structure. The fabric tensor, which represents the directional distribution of the particle contact normal, is known as an […]