METHOD OF CYCLIC SHEAR TEST AT LARGE STRAINS TO DETERMINE DEFORMATION CHARACTERISTICS

Abstract

 A standard test method is proposed for the cyclic shear test considering the recent trend that design earthquake motions become large. At first, various test conditions that can be used in the current test specification are examined, which are drained and undrained, stress control and strain control, and number of loading cycles, etc. It is found that these conditions hardly affect the cyclic shear deformation characteristics up to strain of 0.06%, but results by different test conditions are different to each other at strains larger than 0.06%. Cyclic shear deformation characteristics are also depends on operator's decision at large strains. A test method under the undrained condition, strain controlled amplitude, and three effective loading cycles is proposed as cyclic shear test considering previously discussed effects and matching with constitutive models. Finally, preferable data output is suggested when other test conditions are used.