University of Stavanger

uis.no

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Jasna Bogunović Jakobsen

23.10.2017

http://nn.wikipedia.org/wiki/Uburen#mediaviewer/File:Lysefjordbroen_sett_fra_Sokkanuten.jpg

Research within the Coastal Highway Route E39 project

University of Stavanger

Project supported by NPRA (2014-2019) :

Wind-induced vibrations of long span bridges Motivation:

Safe and cost effective bridge design based on imporved modellingof wind- (and wave)-induced bridge vibrations in complex terrain.

Integrated approach:

Full-scale wind and wind action effects observations.

Dedicated wind tunnel investigations.

Measurement data analysis.

Structural modelling.

Simulation of wind/environmental actions and structuralresponse.

Design criteria

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Research team

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Title and name Financed by Focus on

Prof. J.B.Jakobsen UiS Overall research work management, detailed

planning , measurements, supervision…

Σ expertise based on 55-60 years experience in wind

engineering

Prof. II J.T. Snæbjörnsson NPRA

Postdoc Etienne Cheynet NPRA, since 2016

(UiS PhD, 2016)

Analysis of the full scale measurement data /

Turbulence modelling and simulations /Structural

response analysis in frequency domain

Postdoc Jungao Wang NPRA, since 2016 Finite element structural modelling

Wind and wave load and response analysis in time-

domain / Bridge cable aerodynamics

Dr. Heidi Christiansen UiS PhD, 2016 Bridge cable aerodynamics

PhD student NN UiS Bridge aerodynamics /Fluid-structure interaction

PhD student NN supervised

by Ass. Prof. S. Samarkoon

UiS Structural durability assessment and control of

reinforced concrete constructions: impact of cracks

due to different loading conditions

Pilot investigation on the application of lidars for wind

characterisation in bridge engineering

A Wind measurements around/from an

exisitng bridge - Lysefjord Bridge study

Long range lidar WindCube100S (with UiB and CMR)

Investigation of the overall wind field accross the

fjord

Short range WindScanner system (with DTU, CMR)

Small scale turbulence investigation

upstream and downstream from the bridge deck

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Non-scanning, fixed line-of-sight, measurements:Example of a LOS data by WindCube100S,

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Radial wind velocity recorded by a LOS scan elev=1.8°

azim=39°; 22.05.2014 starting at 16:12:06

B Bjørnafjorden lidar measurements

Bridge in the planning phase !+ 4-5 km wide fjord !

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Lidar and sonic anemometer wind velocity data

comparison

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The along-beam wind velocity data recorded by the lidar Koshava (r = 2248m)

and the anemometers at Ospøya II from 2016-06-24 to 2016-06-28.

Mean value (left) and STD (right) of the

along-beam wind velocity recorded by

the lidar

koshava and the anemometer at

Ospøya II from 2016-06-24 and 2016-

06-28.

Bjørnafjorden lidar measurements

Turbulence intensities recorded

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Cheynet, E., Jakobsen, J.B., Snæbjörnsson, J., Mann, J., Courtney, M., Lea, G. and Svardal, B. (2017),

Measurements of Surface-Layer Turbulence in a Wide Norwegian Fjord Using Synchronized Long-Range

Doppler Wind Lidars, Remote Sensing 9.10: 977.

Poster with more information

=>Basis for C longer NPRA

campaigns at Sulafjorden and

Halsafjorden

=>Comparison between the

wind measurements above the

sea surface and those

acquired from the met masts

on land

Application of lidar

measurements in bridge

engineering presented

on forskning.no

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Wind-induced response of bridges in complex terrain

Complementary approaches to the improved estimation: Full-scale measurements of turbulence

Turbulence modelling / relation to MABL modelling

Simulation of turbulence

Finite element structural modelling

Full-scale observatioins of structural behavior /System identification

Bridge cable vibrations / novel design of stay cable surface

Wave load simulation

Response analysis in frequency and time-domain

Reliability analysis

Broader research environment

Internationial and national collaboration

Collaboration with NPRA

Offshore / marine / CFD group at UiS

Offshore wind energy research (MABL charaterization etc..)

Master students …

..

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Suspension bridge with towers on floating supports Coupled aero-hydrodynamic analysis

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TABLE 4 – Summary of the aerodynamic and hydrodynamic loads for the floating bridge.

Aerodynamic

actions Wind

Quasi-steady buffeting theory;

considering non-linear and coupling terms

Hydrodynamic

actions

Wave

Excitation

force: First order wave excitation force

Radiation

force:

Added mass and damping force

Other

force: Mean drift force

Current TLPs: Mean force

Tethers: Morrison equation with non-linear terms

t

0

-

f(t)=A x(t)+ h(t-τ)x(τ)dτ

2h(τ)= c(ω)cos(ωt)dω

π

t

0

-

f(t)=A x(t)+ h(t-τ)x(τ)dτ

2h(τ)= c(ω)cos(ωt)dω

π

* Second order wave load (sum and difference frequency components to be implemented).

✓ Validation with

full-scale measurement

✓ Validation with

DNV SIMA

FEM + user defined subroutine (in time-domain)

Comprehensive wind-wave load and response simulation

for a bridge with towers on floating supports

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100 years wind and wave conditions; different wave conditions at the two supports

Case study – coupling effect

13Lateral displacement Vertical displacement Torsional displacement

PhD seminar at Sola Strand hotel, June 2017

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Summary

Coastal Highway Route E39 project connects well to theongoing work and triggers further reserach in wind engineeringat UiS.

The research covers the entire spectrum of studies, from thosedevoted to the fundamental understanding of turbulence and the wind load generation mechanism, model-scale and full-scale experimental investigations of loads and bridge dynamicbehaviour, to numerical simulations of load effects on considered E39 bridge designs.

Lot more to investigate and achieve by continuing the researchof high relevance, quality and significant novelty!

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