The Effects of Sedimentary Environment on Geo-Technical Properties of Higashi-Osaka@Sensitive Clay
Keiji INOUE, Kohei SAWA, Yosihisa NAKAYAMA, Hisashi MATSUKAWA, Kazuhiko NISHIDA, Tomio TAMANO, Masanobu KANAOKA and Tatsuaki NISHIGATA
Abstract:The undisturbed samples are obtained from the Higashi-Osaka sensitive clay area in the eastern part of Osaka. By the examination of physical, chemical and engineering properties of the clay, it is clear that the sedimentary environment, leaching and consolidation stress history have effects upon the clay properties, as follows. The clay accumulates under two different types of environment, I.e. the upper is non-marine clay and the lower is marine one. The both clay are influenced considerably by leaching and become high sensitive clay. As the properties of bottom clay of the lower is close to those of non-marine clay because of the leaching and the over-consolidation state, the depth distributions of water content, void ratio and so on are bowed. The strength is mainly depended on the overburden pressure. The consolidation properties of the sensitive clay are affected by the methods of loading, I.e. incremental loading and constant rate of strain loading. And the degree of soil structure appears in the overshoot of e-log p curve of constant rate of strain loading. Key Words:Consolidation properties, Leaching, Marine clay, Overshoot, Sensitive clay