時代の要請に応える土の繰返しせん断変形特性試験の確立を

摘要

A need for research on the test method of cyclic shear deformation characteristics meeting the demands of the times is presented. Following the brief review on the development of the conventional method, the limitation of the conventional method is shown to be up to 0.1% strain or a little larger with several evidences. This strain range is much smaller than required at present because very large earthquake motion is used in the design. At the same time, method for processing the test data is discussed and is shown not to be relevant when considering the large strain. Then, shortages in the constitutive models are discussed from two standpoints; the one is definition of the skeleton or backbone curve and the other is consideration of the initial stress. Finally, some suggestions to develop a new testing method that responds the demands of the times are shown.%1995年兵庫県南部地震が設計分野に与えた影響はいrnくつかあるが，そのうちもっとも大きなものの一つは，rnそれまでの設計指針等で考慮していた地震力が小さかっrnたという認識であろう。これに対して土木分野ではレベrnル2地震動が考慮されるようになった。この様なことrnもあり，土木，建築の分野を問わず，最近は地盤の地震rn応答解析が多く行われるようになってきている。