A unified lateral soil reaction model for monopiles in soft clay considering various length-to-diameter (L/D) ratios

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F20%3A10415798" target="_blank" >RIV/00216208:11310/20:10415798 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Rsb3J0McBQ" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Rsb3J0McBQ</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.oceaneng.2020.107492" target="_blank" >10.1016/j.oceaneng.2020.107492</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A unified lateral soil reaction model for monopiles in soft clay considering various length-to-diameter (L/D) ratios

Popis výsledku v původním jazyce

Large-diameter monopiles are the most commonly used foundation to support offshore wind turbines. Early designs usually adopted pile diameters (D) between 4 and 6 m, which is recently extended to 8 m and will target 10 m in the future. It is increasingly evident that the existing design method (i.e., API&apos;s p-y model) can significantly under-predict the lateral stiffness and capacity of large-diameter monopiles in soft clay, due to ignoring the soil resistances from base shear and base moment which become more pronounces as L/D reduces. In this study, a two-spring approach is proposed, aiming to predict the lateral behaviour of monopiles with varied L/D ratios in a unified manner. In light of the soil flow mechanisms around monopiles, the pure lateral soil resistance above the rotation point (RP) is quantified using a p-y model, while the resistances below the RP including the base shear and base moment are integrated into a moment-rotation spring (characterized by a M-R-theta(R) model) at the RP. It can naturally recover to a p-y model while analyzing flexible piles, where theta(R) = 0 at RP. Formulations of the &apos;p-y + M-R-theta(R)&apos; model (including diameter-related p-y and M-R-theta(R) models, and the depth of the RP) are proposed based on the results of a series of well-calibrated 3D numerical models. The proposed model has satisfactorily reproduced a number of field and centrifuge test results on laterally loaded monopiles with a wide range of L/D ratios (including flexible, semi-rigid and rigid piles), using a unified set of parameters. Compared to the standard p-y model, the adoption of the proposed &apos;p-y + M-R-theta(R)&apos; model is shown to substantially reduce design conservatism.

Název v anglickém jazyce

A unified lateral soil reaction model for monopiles in soft clay considering various length-to-diameter (L/D) ratios

Popis výsledku anglicky

Large-diameter monopiles are the most commonly used foundation to support offshore wind turbines. Early designs usually adopted pile diameters (D) between 4 and 6 m, which is recently extended to 8 m and will target 10 m in the future. It is increasingly evident that the existing design method (i.e., API&apos;s p-y model) can significantly under-predict the lateral stiffness and capacity of large-diameter monopiles in soft clay, due to ignoring the soil resistances from base shear and base moment which become more pronounces as L/D reduces. In this study, a two-spring approach is proposed, aiming to predict the lateral behaviour of monopiles with varied L/D ratios in a unified manner. In light of the soil flow mechanisms around monopiles, the pure lateral soil resistance above the rotation point (RP) is quantified using a p-y model, while the resistances below the RP including the base shear and base moment are integrated into a moment-rotation spring (characterized by a M-R-theta(R) model) at the RP. It can naturally recover to a p-y model while analyzing flexible piles, where theta(R) = 0 at RP. Formulations of the &apos;p-y + M-R-theta(R)&apos; model (including diameter-related p-y and M-R-theta(R) models, and the depth of the RP) are proposed based on the results of a series of well-calibrated 3D numerical models. The proposed model has satisfactorily reproduced a number of field and centrifuge test results on laterally loaded monopiles with a wide range of L/D ratios (including flexible, semi-rigid and rigid piles), using a unified set of parameters. Compared to the standard p-y model, the adoption of the proposed &apos;p-y + M-R-theta(R)&apos; model is shown to substantially reduce design conservatism.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Ocean Engineering

ISSN

0029-8018

e-ISSN

—

Svazek periodika

212

Číslo periodika v rámci svazku

September

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

15

Strana od-do

107492

Kód UT WoS článku

000554925500001

EID výsledku v databázi Scopus

2-s2.0-85087379342