Fundamental Theroy and Experimental Research

Experimental study on static pressure sedimentation for bucket foundation in silty clay

Expand
  • 1. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300350, China; 2. School of Civil Engineering, Tianjin University, Tianjin 300350, China

Received date: 2015-08-31

  Online published: 2018-06-05

Supported by

This work was supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (51321065) , the Program of Introducing Talents of Discipline to Universities (B14012), the International Science & Technology Cooperation Program of China(2012DFA70490)and Tianjin Regional Demonstration Program for Marine Economical Innovation and Development (cxsf2014-15).

Abstract

Successful installation of bucket foundations, a common foundation in ocean engineering, is a prerequisite for normal use. Static pressure sedimentation tests on the bucket foundations with different length-to-diameter ratios are performed in homogeneous silty clay to determine the change of pressure inside and outside the cylinder wall and the cylinder end during the static pressure sedimentation process. The results show that the inner pressure is in the form of double broken line. The outer pressure increases linearly, and the lateral extrusion of the wall is the main reason for the inner pressure generation. The soil squeezing effect in the interior wall is much significant than the exterior wall. The soil squeezing extent of the exterior is small on the upper portion and large on the lower portion of the foundation, which has a linear relationship with the IFR. The tip resistance is directly related to the strength of the soil. According to the standard, based on the undrained shear strength and the CPT, the lateral and tip resistance can be calculated accurately. Due to the difference of soil squeezing effect, ? and kf will take larger value when the inner resistance is calculated. The major part of resistance is tip resistance, and then lateral resistance becomes the major during installation. The resistance and the development of soil plug are not sensitive to the speed range of 0.1-0.2 cm/s. The soil squeezing effect and resistance characteristic of bucket foundations with length-to-diameter ratio between 1 and 2 are similar.

Cite this article

LIAN Ji-jian, MA Yu-xiang, WANG Hai-jun, WANG Peng-wen, JIANG Xing-yu, . Experimental study on static pressure sedimentation for bucket foundation in silty clay[J]. Rock and Soil Mechanics, 2017 , 38(7) : 1856 -1862 . DOI: 10.16285/j.rsm.2017.07.002

Outlines

/