The Seepage and Soil Plug Formation in Suction Caissons in Sand Using Visual Tests

Liquan Xie,Tiantian Lin,Shili Ma

doi:10.3390/app10020566

Abstract

The rapid development of offshore wind energy in China is becoming increasingly relevant for movement toward green development. This paper presents the results of visual tests of a suction caisson used as foundation for offshore wind turbines. The distribution of hydraulic gradients of sand at the mudline in the caisson was obtained to find out the relationship with the heights of soil plugs. The relationship equation was proposed and obtained by using quadratic regression, guiding project designs, and construction. It was found that there was no soil plug in the caisson when small suction was applied during the suction penetration. The relationship between the heights of the soil plugs and the hydraulic gradient of the soil was proposed and obtained by using quadratic regression to predict (roughly) the height of soil plugs in suction caissons in sand during suction penetration. The influence of settlement outside caissons on the soil plug was found to decrease as the buried depth rose.

Highlights

In the past few decades, it has become increasingly important to rapidly develop the offshore wind industry, which provides practical sources of energy with a low carbon footprint [1,2]
This paper presents the results of visual tests of a suction caisson used as a foundation for offshore offshore wind turbines
The seepage field can be visualized where the carmine stain flows along streamlines in the soil around the suction caisson

Summary

Introduction

In the past few decades, it has become increasingly important to rapidly develop the offshore wind industry, which provides practical sources of energy with a low carbon footprint [1,2]. The suction caisson, being installed economically and efficiently into soil deposits, has been increasingly used as a competitive foundation for offshore wind turbines in deep water [4,5]. The induced seepage flow through highly permeable sand into the caisson interior can create some negative effects To investigate these effects, a number of studies have been completed, and they show that the seepage facilitates the installation process at the caisson tip and along the inner wall [10,11,12,13]. This paper presents the results of visual tests of a suction caisson used as a foundation for offshore offshore wind turbines. Obtained by using quadratic regression, guiding project designs, and construction

Experimental Program

Visual Seepage Paths

Hydraulic

D E as follows: F expressed

Conclusions