Development of a Multi-Purpose Shear Test System─Torsional Shear Apparatus

• Main Authors: Chen-yuan Lee, 李程遠
• Other Authors: Yii-Wen Pan
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/54106205805094189113

碩士 === 國立交通大學 === 土木工程系 === 91 === Slope failure often occurs in soft rock due to the low strength of the material. This project aims to study the material mechanics of the soft rock relevant to common slope failure in soft rock. Unlike brittle rock, soft rock often contains few joints. Unless for slope failure resulted from structural instability, relevant material characteristics of soft rock related to slope failure might include (1) degradation, (2) strain softening, (3) creep, and (4) local stress failure. It is more appropriate for using residual strength instead of peak strength in modeling the progressive failure of slope stability in soft rock. Conventional tests of shear strength for geo-materials, to various extents, may not obtain the correct residual strength of material. This project has designed and built a servo-controlled ring shear apparatus appropriate for testing the mechanical behavior and properties of soft rock. Using the ring shear test, the residual strengths can be obtained. The equipment was designed to conduct torsional shear tests under various conditions including constant normal force, constant volume, and constant stiffness, especially for soft rock specimen. The purpose is to obtain residual shear strength under various conditions using a same set of equipment. A series of experiments were carried out to verify the design objectives and to obtain the residual strength of a soft rock. It was confirmed the designed equipment could be operated according to the designed purposes.