Effect of loading rate on the pullout capacity of offshore bucket foundations in sand. (15th August 2020)

• Record Type: Journal Article
• Authors: Vicent, Ssenyondo; Kim, Sung-Ryul; Van Tung, Do; Bong, Taeho
• Is Part Of: Ocean engineering. Volume 210(2020)
• Publication Date: 2020-08-15
• Subjects: Bucket foundation -- Pullout capacity -- Drainage condition -- Loading rate -- 1 g model tests; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2020.107427
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: A series of 1 g model tests was performed to investigate the effect of loading rate on the vertical pullout capacity of offshore bucket foundations in sand. The bucket model had a length-to-diameter ratio of 1.0. Loading rates varied from 0.004 N/s to 2.05 N/s. The pullout load increased with bucket displacement and loading rate. The loading rate of 0.004 N/s induced drained conditions with negligible suction pressure and high skin resistance. Increasing the loading rate induced high suction pressures inside the bucket. The bucket pullout capacity increased with bucket displacement and loading rate. Suction pressure increased with bucket displacement and loading rate and contributed considerably to the pullout capacity. The bucket resistance to pullout load increased with the increase in loading rate. Equations were proposed to evaluate the drained and undrained pullout capacities of the bucket. Highlights: Vertical pullout capacity of the bucket was investigated by 1-g experimental tests. Drainage conditions changed from drain to undrain with the increase of the loading rate. Pullout capacity of the bucket increased with increase of loading rate. Suction pressure increased with loading rate and majorly contributed to the pullout capacity. Equations have been proposed to estimate the pullout capacity for varying drainage conditions.