Effect of sitting time on the breakout force of mat foundation on soft marine clay seabed. (15th August 2021)

• Record Type: Journal Article
• Authors: Zhang, Qi; Fang, Tianyi; Ye, Guanlin; Liu, Guojun; Wang, Rong; Tian, Yinghui
• Is Part Of: Ocean engineering. Volume 234(2021)
• Publication Date: 2021-08-15
• Subjects: Breakout force -- Mat foundation -- Field test -- Numerical analysis -- Effective stress; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2021.108770
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: Jack-up offshore platform mat foundation has lower requirements on the bearing capacity on clay seabed than spudcan foundation, which is more suitable for the soft clay seabed. It is of great significance to reveal the mechanism of breakout force of mat foundation to ensure the safety and stability of offshore platform. In this study, field tests with different consolidation times were conducted to investigate the breakout force of mat foundation on soft marine clay seabed. Field results show that the suction generated by negative pore pressure in the seabed soil accounted for most of the breakout force, generally up to 90%. Then, the effects of consolidation time, preloading and uplift rate on the effective stress and breakout force were numerically studied. Numerical results show that the breakout force has a linear relationship with the consolidation degree of seabed soil. Under the same degree of consolidation, the breakout force per unit area increases with the increase of preloading. The uplift process changes from drained to undrained as the uplift rate increases. Highlights: Field tests were conducted to study the breakout force of mat foundation. Suction generated by negative pore pressure accounted for most of the breakout force. Breakout force has a linear relationship with the consolidation degree of seabed soil. Uplift process of mat foundation changes from drained to undrained as uplift rate increases.