大小様々な液状化ひずみ履歴を与えた複数回液状化試験と消散エネルギーを用いた分析  [in Japanese] BEHAVIOR OF MULTIPLE-LIQUEFACTION UNDER SMALL TO LARGE STRAIN LEVELS AND ITS ANALYSIS BASED ON DISSIPATED ENERGY  [in Japanese]

Access this Article

Author(s)

Abstract

2011年の東北地方太平洋沖地震では,過去に発生した液状化地点と同一の地点において液状化現象が確認された.今後想定される大地震の液状化対策を検討するうえで,実際の地震と同様に大小様々な液状化履歴を与えた場合の砂質地盤の複数回液状化特性変化を把握し,その上で予測手法の開発や適切な液状化対策を実施する必要がある.本研究では,豊浦砂で作製した中空円筒供試体に対して,多層リングせん断試験装置で一次元圧縮と定体積繰返しせん断試験を,各液状化段階で大小様々な両振幅せん断ひずみを設定して複数回実施した.その後,得られた応力-ひずみ関係に対して繰返しせん断過程中の消散エネルギーを算定し,直後の液状化段階の液状化強度との相関について検討を行った.

 After the 2011 Off the Pacific Coast of Tohoku Earthquake in Japan, it was found that liquefaction can appear at multiple times in the same sites. This issue created a great concern about the reoccurrence of multiple-liquefaction in the future earthquakes. In this study, a series of cyclic simple shear tests was performed on dry Toyoura sand while keeping the specimen volume constant using a stacked-ring shear apparatus. In order to study the behavior of multiple-liquefaction under small to large strain levels, the same specimen was sheared at different levels of maximum shear strain double amplitude on each liquefaction stage. In addition, in order to investigate how the occurrence of previous liquefaction may affect the soil behavior during future liquefaction stages, an analysis based on dissipated energy was conducted.

Journal

  • Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE))

    Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)) 72(4), I_167-I_176, 2016

    Japan Society of Civil Engineers

Codes

Page Top