Effect of humidity and interlayer cation on frictional strength of montmorillonite

Hiroshi Tetsuka1, Ikuo Katayama2, Hiroshi Sakuma3 and Kenji Tamura3, (1)Hiroshima University, Earth and Planetary Systems Science, Higashi-Hiroshima, Japan, (2)Hiroshima University, Higashi-Hiroshima, Japan, (3)National Institute for Materials Science, Tsukuba, Japan