Acceleration Data Sonification

Thanks to the generous structural monitoring engineers at NTNU, I have access to an incredible range of accelerometer data from the Hardanger Bridge. It only took one more specific search term, and is published under a creative commons (cc-by) license.

Now the fun really starts – downloading the csv files: LowWind, HighFreq; MaxLift, LowFreq, MaxPitch, HighFreq (which I misread as MaxPatch and thought OMG they have sonified it already! Although perhaps they have. I still need to write and make contact) MaxDrag, LowFreq… The monitoring sensors are in place since 2013, there is seven years of data. And the storms – Storm Nina, Storm Ole, Storm Roar, Storm Thor!

Image Credit: NTNU Department of Structural Engineering, Trondheim

Wind and Acceleration Data from the Hardanger Bridge

By Aksel Fenerci, Knut Andreas Kvåle, Øyvind Wiig Petersen, Anders Rønnquist, Ole Øisethhttps://doi.org/10.21400/5ng8980s Published 18-08-2020 at Norges teknisk-naturvitenskapelige universitet 2764 views

The dataset consists of long-term wind and acceleration data collected from the Hardanger Bridge monitoring system. The data are collected through wind sensors (anemometers) and accelerometers that are installed on the bridge. The dataset includes both the raw data (in “.csv” format) and the organized data (with “.mat” extension based on hdf5 format). Downloadable zipped folders contain monthly data with different frequency resolutions, special events (storms, etc.) and the raw data. Details on the organization of the data can be found in the readme file and the data paper, both of which can be found in the dataset.

Resource type: Dataset

Category: Teknologi, Bygningsfag, Konstruksjonsteknologi

Process or method: GPS, Wi-Fi, accelerometers, anemometry, signal processing

Geographical coverage: Hardanger, Norway

Fenerci, A., Kvåle, K. A., Petersen, Ø. W., Rönnquist, A., & Øiseth, O. A. (2020). Wind and Acceleration Data from the Hardanger Bridge. https://doi.org/10.21400/5NG8980S

Datasets and Weather

Ok I’m breaking this down now – the CSV files are by year and month eg. Raw 2015 1.

Storms happen in January, Storm Nina: 10th Jan 2015, Storm Thor: 29th Jan 2016.

So to focus on the storms, go for the first month. I can’t use their smaller already selected and edited mat files in the data sonification tool. Maybe it’s possible to conver mat to csv? (oh that question that opens up a whole new can of worms!)

And have just discovered that my idea works to replace the audio files in the twotone sampler with my own bridge sounds… except that I have to go through the meticulously and make each NOTE as a bridge sound, as they move up and down on the scale while playing the data. I think that’s enough for today. Back to the sensors.

For now I’m taking the full month raw csv files and parsing them by date. You gotta start somewhere – Storm Nina go!

Poetic Storm Nina Video Homage

Storm Norway – Sandvikjo stormen Nina 10.01.2015 – Halsnøy by monica

MELLOM BAKKAR OG BERG
Ivar Aasen

Mellom bakkar og berg ut med havet
heve nordmannen fenge sin heim,
der han sjølv heve tuftene grave
og sett sjølv sine hus oppå dei.

Han såg ut på dei steinute strender;
der var ingen som der hadde bygd.
«Lat oss rydja og byggja oss grender,
og så eiga me rudningen trygt»

Han såg ut på det bårute havet,
der var ruskut å leggja utpå,
men der leikade fisk nedi kavet,
og den leiken, den ville han sjå.

Fram på vinteren stundom han tenkte:
«Gjev eg var i eit varmare land!»
Men når vårsol i bakkane blenkte,
fekk han hug til si heimlege strand.

Og når liane grønkar som hagar,
når det lavar av blomar på strå,
og når netter er ljose som dagar,
kan han ingen stad venare sjå.

Sud om havet han stundom laut skrida:
Der var rikdom på benkjer og bord,
men ikring såg han trelldomen kvida
og så vende han atter mot nord.

Lat no andre om storleiken kivast,
lat deim bragla med rikdom og høgd,
mellom kaksar eg inkje kan trivast,
mellom jamningar helst er eg nøgd.

Lyd Mellom bakkar og berg ut med havet

BETWEEN HILLS AND MOUNTAINS Ivar Aasen

Between hills and mountains out to sea raise the Norwegian get his home, where he himself raise the tufts dig and put their houses on top of them. He looked out on the rocky beaches; there was no one who had built there. “Let us clear and build our villages, and then own the rudder safely » He looked out on the stretcher sea, there was debris to lay on, but there were fish playing down the cave, and that toy, he wanted to see. Until the winter he sometimes thought: “I wish I were in a warmer country!” But when the spring sun on the slopes shone, he got the urge to say home-grown beach. And when liane greens like pastures, when it blooms of flowers on straw, and when nights are as bright as days, he can see no city venare. South of the sea he sometimes loudly slid: There was wealth on benches and tables, but around he saw the bondage quiver and then he turned north again. Let no others about the size kivast, let them brag with wealth and heights, between cookies I can not thrive, between jams preferably I am satisfied.

Sound: Between hills and mountains out to sea

Wind-induced response of long-span suspension bridges subjected to span-wise non-uniform winds: a case study

Master thesis – NTNU Norwegian University of Science and Technology. Department of Structural Engineering. [E.M. Forbord & H. Hjellvik]

The response has also been predicted using wind data from the Hardanger Bridge, and the predictions have been compared to the measured response. Uniform profiles of wind speed and turbulence have been given different values based on the measured data, more specifically the mean value of all sensors and the value from the midmost wind sensor. It is seen that the choice of value does not affect the accuracy of response predictions. No matter what values are chosen, the predictions are quite inaccurate in general. lntroducing a non-uniform profile of mean wind speed makes the predictions slightly better in some cases, but not noteworthy, and the accuracy is still relatively low. When also including the non-uniformity of turbulence in the response calculations, the predicted response is reduced and the accuracy worsened with respect to the measured response. Accounting for the non-uniformity of self-excited forces shows almost no effect on the predictions. It is concluded that non-uniform wind profiles do not improve the accuracy of predicted bridge response, and that other uncertainties in the calculation methods have larger impact on the predictions than whether the non-uniform profiles are included or not.

2.1 Random Vibration Theory

6.2 Influence of Non-Uniform Turbulence Standard Deviations

In this section, the influence of span-wise non-uniform turbulence standard deviations on the dynamic response will be presented. Three wind speed profiles have been analysed with different turbulence std profiles. The wind speed profiles used are the linear profile and the sinus profile shown in Figure 5.5a and 5.5d, in addition to a uniform wind speed profile. The three different turbulence std profiles shown in Figure 6.15 are studied. They all have the same integrated sum along the span to make them comparable. The two non-uniform turbulence std profiles chosen have the opposite shapes of the wind speed profiles used in this section, because this is often seen in the measurement data from the Hardanger Bridge. Both of these turbulence std profiles will be compared to uniform turbulence standard deviations, for all the three wind speed profiles. The horizontal turbulence std has a span­ wise mean value of 20% of the wind profile’s mean wind speed, and for the vertical component the corresponding value is 10%. The effect of turbulence std on the response is included in the calculations through the wind spectra, which have a quadratic dependancy on the turbulence std, as shown in Eg. (2.40). The span-wise variation of wind speed is also included in the formula. Therefore, to study the effect of the turbulence std profiles isolated, the response using a uniform wind speed profile and different turbulence std profiles has been calculated. In addition comes the linear and sinus wind profiles, to study if the same turbulence std profiles have different effect on these than on the uniform wind speed profile. The calculated response will only be presented for wind profiles with the mean wind speed of 10 mis, because the trends, the shape and differences of the response along the span are nearly the same for all mean wind speeds for the different wind speed profiles.

6.3 Influence of Non-Uniform Self Excited Forces

To study the influence of span-wise non-uniform self-excited forces on the dynamic response, several wind speed profiles have been numerically tested with both uniform and non-uniform self-excited forces. The non-uniform self-excited forces are caused by the non-uniform wind profile. The re­ sponse is predicted with uniform self-excited forces where the aerodynamic properties are dependent on the mean wind speed of the wind profile, and with non-uniform self-excited forces where the aero­ dynamic properties vary along the span with the wind speed. Toen the bridge response in both cases are compared. The wind profiles tested are presented in Figure 5.5. As in section 6.1, the standard de­ viations of turbulence components are span-wise uniform, such that the influence of the non-uniform self-excited forces are investigated separately. The horizontal and vertical turbulence standard devi­ ations have been set to 20 and 10%, respectively, of the horizontal mean wind speed.

The influence of the non-uniform turbulence standard deviation has connection to the shape of the wind speeds along the span. As discussed previously, the response shifts to where the wind speeds is largest. The same can be said about the turbulence std. It was seen that the wind is dominating and shifts the response more than the turbulence std, for this particular shapes and ratio between the mean wind speed and standard deviation of the turbulence components. The horizontal shift in the response due to the non-uniform turbulence std comes from the cross-spectral densities of the turbulence components which is high when two points with large turbulence std are considered.

The effect of including the non-uniform self-excited forces on the response increase with the mean wind speed of the wind profile. The difference between the response using non-uniform and uniform self-excited forces are largest for the highest mean wind speeds studied. The lateral response using non-uniform self-excited forces deviates less from the response using uniform self-excited forces compared to the vertical and torsional response. This is due to the aerodynamic derivatives which has been taken as zero. The reason for the large ratios in the vertical and torsional direction is the aerodynamic derivatives that reduce the total damping and stiffness of the structure as mentioned. For lower mean wind speeds, 10-20m/s, the difference is below 10% for all response components.

Masters Thesis NTNU 2017 permanent link

I think it’s safe to say they haven’t sonified it… yet!

Here are a few more links open from my research on the Hardanger Bridge

Official Website https://www.vegvesen.no/vegprosjekter/Hardangerbrua/InEnglish/the-hardanger-bridge

General Norway Bridges info https://www.vegvesen.no/en/roads/Roads+and+bridges/Bridges

The Neglected Bridges of Norway

https://www.vg.no/spesial/2017/de-forsomte-broene/kart/index-eng.php

AllplanInfrastructure

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