ISSN: 0149-6115
Page Count: 13

Shear Banding in a Sedimentary Soft Mudstone Subjected to Plane Strain Compression

Hayano, K
Research associate,Institute of Industrial Science (IIS), University of Tokyo,

Maeshiro, T
Engineer,Electric Power Development. Co. Ltd.,

Tatsuoka, F
Professor,University of Tokyo,

Sato, T
Research associate,Institute of Industrial Science (IIS), University of Tokyo,

Wang, L
Research Engineer,Chuo Kaihatsu Corporation,

Kodaka, T
Research associate,Kyoto University,

(Received 30 June 1997; accepted 25 September 1998)

Abstract

A plane strain compression (PSC) testing system to observe shear banding in softrock was developed. The deformation characteristics of shear band in a sedimentary soft mudstone were evaluated by locally measuring axial and lateral deformations of specimens in drained PSC tests. Shear deformation and dilatancy of shear band that occurred between the peak stress state and the start of the residual stress state were on the order of 1 and 0.5 mm. Dilatancy of the shear band continued during the residual stress state, resulting in a high-residual friction angle mobilized along the shear band. Shear band deformation characteristics of two other sedimentary softrocks were obtained from axial strains measured locally in triaxial compression tests based on the stress-state dilatancy relationship obtained from the PSC tests.

Keywords:
sedimentary soft mudstone, shear band, plane strain compression, local deformation measurements, shear deformation, dilatancy

Paper ID: GTJ11317J
DOI: 10.1520/GTJ11317J
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