An Investigation on Horizontal Resistance of Piles and Sheet Piles during Earthquakes.

地震期间桩和板桩水平阻力的研究。

• 批准号: 04402040
• 负责人: KIMURA Tsutomu
• 金额: $ 6.91万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-04402040/
• 关键词: earthquakes; pile groups; sheet piles; plasticity index; centrifuge modelling; intermediate soil; liquefaction; 軟弱粘性土; 低塑性; 地盤反力係数

Dynamic centrifuge tests were carried out using a laminar box in which model pile groups were embedded in a soil layr so as to study the dynamic response of piles and soil mass and their dynamic interaction. We used four different soils (low plasticity soil : Ip=2, Intermediate soil : Ip=10, Clay : Ip=30 and Toyoura Sand) to make soil layrs. A random wave simulating the El Centro record was applied to the soil mass. Comclusions derived from these are as follows.1) In case of soils with extremely low plasticity, it was observed that the rigidity of ground was reduced during the early stage of earthquakes and as a result, the amplitude of the acceleration of model pile structures was much smaller.2) The ratio of the observed acceleration spectrum of a model pile structure to the input acceleration spectrum is larger for the higher plasticity soil layr.3)In case of lower plasticity soil layr, less bending moment was observed in model piles during earthquakes but more permanent displacement was measured.Dynamic centrifuge model tests with sheet piles were also conducted applying sinusoidal wave as input motion to the model ground. The observed strains in sheet piles were smaller and observed horizontal irrecoverable displacement of sheet piles were larger for the ground with less resistance for liquefaction.

采用将模型桩群埋入土层的层流箱进行动力离心试验，研究桩与土体的动力响应及其动力相互作用。我们使用四种不同的土壤（低塑性土壤：Ip=2、中级土壤：Ip=10、粘土：Ip=30 和丰浦沙）来制作土层。将模拟 El Centro 记录的随机波应用于土体。由此得出的结论如下： 1)对于塑性极低的土体，观察到地震早期地基刚度降低，导致模型桩结构加速度幅值为2) 对于较高塑性土层，模型桩结构观测到的加速度谱与输入加速度谱的比率较大。3) 在较低塑性土层的情况下，在模型桩过程中​​观察到的弯矩较小地震，但更永久的位移是还进行了板桩动态离心机模型试验，将正弦波作为模型地面的输入运动。对于液化阻力较小的地基，观察到的板桩应变较小，观察到的板桩水平不可恢复位移较大。

项目成果

山内公介,吉迫和生,廣岡明彦,竹村次朗,木村孟: "軟弱地盤における自立矢板壁の地震時挙動" 第29回土質工学研究発表会発表講演集. 2. 1091-1094 (1994)

山内幸介、吉佐子一雄、广冈明彦、竹村次郎、木村萌：“软土地基中自承式板桩墙的地震性能”第29届土壤工程研究会议论文集2. 1091-1094（1994）。

A.Takahashi, K.Yamauchi, A.Hirooka and J.Takemura: "Effects of loading rate on behavior of piles subjected to repeated lateral loading." Proc.50th Annual Conference on the JSCE. vol.II.1855-1856 (1995)

A.Takahashi、K.Yamauchi、A.Hirooka 和 J.Takemura：“加载速率对承受重复侧向荷载的桩的行为的影响。”

井上幸一,渡部要一,未政直晃,竹村次朗,酒井貴之: "裏込め荷重を受ける軟弱地盤中の杭橋台の安定性に関する研究" 第28回土質工学研究発表会発表講演集. 2. 1855-1856 (1993)

Koichi Inoue、Yoichi Watanabe、Naoaki Misama、Jiro Takemura、Takayuki Sakai：“回填荷载作用下软土地基桩台稳定性研究”第 28 届土壤工程研究会议论文集 2. 1855 年 -1856 年（1993 年）。

古荘 伸一郎,木桧 敏明,広岡 明彦,竹村 次朗,木村 孟: "せん断箱を用いた遠心模型振動実験" 第28回土質工学研究発表会発表講演集. (1993)

Shinichiro Furuso，Toshiaki Kokuhi，Akihiko Hirooka，Jiro Takemura，Meng Kimura：“使用剪切箱的离心模型振动实验”第28届土壤工程研究会议论文集（1993）。

K.Inoue, Y.Watabe, T.Sakai, J.Takemura and N.Suemasa: "Stability of piled bridge on soft clay subjected backfill loading." Proc.28th National Conference on SMFE. vol.II.1855-1856 (1993)

K.Inoue、Y.Watabe、T.Sakai、J.Takemura 和 N.Suemasa：“回填荷载作用下软粘土上桩桥的稳定性”。