Stability of Suction Foundation against Eccentric Loading

吸力基础抗偏载稳定性

• 批准号: 15360254
• 负责人: ZEN Kouki
• 金额: $ 9.79万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15360254/
• 关键词: Suction foundation; bearing capacity; 海洋基礎; 中空円筒基礎; 傾斜荷重; 模型実験; 有限要素解析

In this study, model test and finite element analysis were performed to clarify the mechanism of bearing capacity of suction foundation against inclined loading. The main findings for the bearing capacity against inclined loading condition are followed ;1)Horizontal bearing capacity of suction foundation increases with decreasing ratio of inner diameter and outer diameter. In case of D/B=1.1 and vertical bearing capacity=44.1N, the horizontal bearing capacity decreases about 40 and 50% compared to a standard foundation.2)Horizontal bearing capacity increases as D/B increases and relative density increases.3)Wedge of strain field is generated around and below a suction foundation. Especially, strain is concentrated adjacent to a foundation.4)Sliding failure is shown in ground under the foundation if D/B is small. However, wedge failure is shown as D/B and inclined angle increase. The pull out failure is shown between sliding failure and wedge failure.5)In same loading condition, displacement of foundation increases with increasing D/B and decreasing ration of inner and outer diameter.In addition, the model test is performed to evaluate the bearing capacity mechanism against eccentric loading. the main findings of suction foundation against eccentric loading are followed ;1) Vertical bearing capacity decreases with increasing eccentric distance of loading.2) Bearing capacity decreases as the ratio of inner and outer diameter increases.3) The shearing ratio of resistance for suction foundation is determined by the sharp of foundation.4) Tip resistance is developed at beginning of loading. After that, suction foundation lactates around the tip of foundation and lateral resistance are gradually developed.5) In the case of small eccentric distance, large strain field are shown adjacent to foundation compared to large eccentric distance.Finally, the pull out test using clayey ground is performed to clarify the mechanism of generating suction and failure mode.

本研究通过模型试验和有限元分析，阐明了吸力基础抗倾斜荷载的承载机理。倾斜荷载条件下承载力的主要发现如下：1）吸力基础的水平承载力随着内径与外径之比的减小而增大。当D/B=1.1，竖向承载力=44.1N时，水平承载力比标准基础下降约40%和50%。2）水平承载力随着D/B的增加和相对密度的增加而增加。3）吸力基础周围和下方产生应变场楔形。特别是，应变集中在地基附近。4)如果D/B较小，则地基下方的地面会出现滑动破坏。然而，楔块失效表现为D/B和倾斜角增加。拔出破坏表现为介于滑动破坏和楔形破坏之间。5)相同荷载条件下，基础位移随着D/B的增大和内外径比的减小而增大。另外，通过模型试验评价了偏载承载力机理。吸力基础抗偏心荷载的主要发现如下：1）竖向承载力随着荷载偏心距的增加而减小。2）承载力随着内径与外径之比的增大而减小。3）吸力基础的阻力剪切比由基础的锐度决定。4）在加载开始时产生尖端阻力。此后，基础尖端周围的吸力基础乳状体和侧向阻力逐渐发展。5）在小偏心距离的情况下，与大偏心距离相比，在基础附近表现出大的应变场。最后，进行了粘土地基的拔出试验，以阐明产生吸力的机理和破坏模式。

项目成果

伊藤達也, 善功企, 陳光斉, 笠間清伸: "粘土地盤におけるサクション基礎の引抜き時の破壊モードについて"第38回地盤工学研究発表会発表講演集. (CD-ROM). 1603-1604 (2003)

Tatsuya Ito，Gonggi Shan，Guangqi Chen，Kiyonobu Kasama：“关于粘土地基吸力基础拔出时的破坏模式”第38届岩土工程研究会议论文集（CD-ROM）1603-1604。

出口信太郎, 善功企, 陳光斉, 笠間清伸: "周辺地盤の密度の違いに着目したサクション基礎の支持力特性と破壊モード"第38回地盤工学研究発表会発表講演集. (CD-ROM). 1601-1602 (2003)

Shintaro Deguchi，Gonggi Zen，Guangqi Chen，Kiyonobu Kasama：“关注周围地面密度差异的吸力基础的支撑能力特征和破坏模式”第38届岩土工程研究会议论文集（CD-ROM）1601 -1602。 ）

Experimental and Analytical Studies on Bearing Capacity of Suction Foundation

吸力基础承载力试验与分析研究

• 发表时间: 2003
• 期刊: Proceeding of The Thirteenth International Offshore and Polar Engineering Conference
• 作者: C.Lertsima;T.Chaisomphob;E.Yamaguchi;楮佐古 智広;Kouki ZEN et al.
• 通讯作者: Kouki ZEN et al.

伊藤達也, 善功企, 陳光斉, 笠間清伸: "サクション基礎の引抜き抵抗力の支持力公式"土木学会第58回年次学術講演会講演概要集. (CD-ROM, DISC1). 547-548 (2003)

Tatsuya Ito、Gonggi Shan、Guangqi Chen、Kiyonobu Kasama：“吸力基础抗拔力的支撑能力公式”日本土木工程师学会第 58 届学术年会摘要（CD-ROM，DISC1）。 548（2003）

伊藤達也, 善功企, 陳光斉, 笠間清伸: "加圧密地盤におけるサクション基礎の引抜き抵抗力に関する模型実験"土木学会西部支部研究発表会講演概要集. 第1分冊. A-250-A-251 (2004)

伊藤达哉、山功基、陈光启、笠间清信：《压实致密地基中吸力地基抗拉拔模型实验》日本土木工程学会西部分会讲座摘要第 1 卷 A-250。 -A-251 (2004))