Norwegian Geotechnical Institute (NGI) Digital Archive
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Building vibration induced by sonic boom - field test in Russia
Get PDFInfrasound and audible sound at very low frequency from sources such as military aircrafts, explosions and wind mills can induce building vibration involving both rattling and whole-body vibration strong enough to cause annoyance. Sonic boom is of special interest in this context due to its very low frequency content that coincides with the most important frequency range for both building vibration and human perception. This paper presents results from field tests with measurements of noise and building vibrations from sonic booms performed at the Tretyakovo airport in Russia. Transmission loss from outdoor to indoor noise, noise induced floor vibration and whole building vibration are determined. Furthermore, the measured acoustic vibration admittance is used to estimate vibration values in the same building from low boom flight passages using synthesized sound pressure time series. Boom induced floor vibration both from the measured flight passages in Russia and from synthesized low boom time series are estimated also for a lightweight wooden building, using previously measured acoustic vibration admittances. The results clearly show perceptible levels of vibrations from sonic boom along with a great influence of the building type which indicates that there can be a big difference between the European countries depending on the building tradition. Finally, it is shown that outdoor sound levels weighted with the C-curve correlates best with frequency weighted floor vibration values.Building vibration induced by sonic boom - field test in RussiapublishedVersio
3D stability analyses of Skjeggestad landslide
Get PDFIn 2015, a sudden landslide caused the failure of one of the pillars supporting the southern lanes of the Skjeggestad Bridge near Mofjellbekken on Expressway E18. The transportation corridor was closed to traffic for 17 months. To investigate the cause of the failure, an assessment of slope stability is necessary. Usually, limit equilibrium analysis of the middle two-dimensional (2D) cross-section is modelled. The Skjeggestad landslide geometry was not close to a 2D case, and three-dimensional (3D) modelling is more appropriate to analyse the slope. The paper calculates the stability of the slope that failed and compares the results of 3D finite element analyses with classical limit equilibrium and 2D finite element analyses. The analyses were run in the Novapoint GeoSuite Stability software. The soil parameters, including their statistical values, were obtained with the GeoSuite Soil Data Interpretation (SDI) module. A companion paper at this conference analyses the pillar neighbouring the landslide with the module GeoSuite Piles. The paper illustrates the importance of 3D effects in a stability analysis. The results of the analyses also illustrate the need to include appropriate consideration of any strain-softening and spatial variation of soil properties.publishedVersio
The distribution of persistent, mobile and toxic (PMT) pharmaceuticals and personal care products monitored across Chinese water resources
Get PDFHazard classifications have recently been introduced for persistent, mobile and toxic (PMT) and very persistent and very mobile (vPvM) substances, which are those that negatively impact water resources if substantially emitted into the environment. Many pharmaceuticals and personal care products (PPCPs) may meet this classification. Our study focused on 169 detected PPCPs in surface water, groundwater and drinking water in China among a total of 432 PPCPs that were monitored for across 75 studies. We assessed if these could be classified as PMT/vPvM substances based on the recent European criteria for industrial substances. For most PPCPs, persistency half-life data were lacking; therefore, definitive classifications could not be made. In surface water, 52 (37.7 %) of the detected PPCPs met, or were strongly suspected to meet, the PMT/vPvM criteria. Over half of these were antibiotic compounds. The industrialized Yangtze, Haihe and Pearl river basins were the most impacted. We hypothesized the proportion of PPCPs monitored meeting the PMT/vPvM criteria in drinking water and groundwater would be larger than surface water. This was supported as 44.3 % of PPCPs in these media met, or based on weight-of-evidence likely meet, the PMT/vPvM criteria; though, a definitive comparison was hindered by a lack of persistence data.publishedVersio
Effects of Organic Carbon Origin on Hydrophobic Organic Contaminant Fate in the Baltic Sea
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AEM in norway: A review of the coverage, applications and the state of technology
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Regional Analyses of Rainfall-Induced Landslide Initiation in Upper Gudbrandsdalen (South-Eastern Norway) Using TRIGRS Model
Get PDFIn Norway, shallow landslides are generally triggered by intense rainfall and/or snowmelt events. However, the interaction of hydrometeorological processes (e.g., precipitation and snowmelt) acting at different time scales, and the local variations of the terrain conditions (e.g., thickness of the surficial cover) are complex and often unknown. With the aim of better defining the triggering conditions of shallow landslides at a regional scale we used the physically based model TRIGRS (Transient Rainfall Infiltration and Grid-based Regional Slope stability) in an area located in upper Gudbrandsdalen valley in South-Eastern Norway. We performed numerical simulations to reconstruct two scenarios that triggered many landslides in the study area on 10 June 2011 and 22 May 2013. A large part of the work was dedicated to the parameterization of the numerical model. The initial soil-hydraulic conditions and the spatial variation of the surficial cover thickness have been evaluated applying different methods. To fully evaluate the accuracy of the model, ROC (Receiver Operating Characteristic) curves have been obtained comparing the safety factor maps with the source areas in the two periods of analysis. The results of the numerical simulations show the high susceptibility of the study area to the occurrence of shallow landslides and emphasize the importance of a proper model calibration for improving the reliabilitypublishedVersio
From landfills to landscapes—Nature-based solutions for water management taking into account legacy contamination
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Effect of Extreme Weather Events on Contaminant Transport From Urban Run-Off to a Fjord System
Get PDFUrbanization has resulted in increased contaminant run-off in densely populated areas. Climate change is expected to result in a higher frequency of extreme weather events including torrential rainfall and storms. The contaminant levels of polycyclic aromatic hydrocarbons (PAH), chlorinated paraffins (CPF) and selected metals, in a small urban river were monitored during snow-melting and rainfall events to quantify the contribution to the contamination load of receiving waters of the inner Oslo fjord, Norway. Suspended particulate matter (SPM) was characterized with respect to levels of contaminants as well as toxic response using a battery of bioassays. The contaminant flux from the river to the fjord was quantified and assessed relative to sediment data. Historic data for near-shore sediment samples from the fjord were used to document urban input. The results show a clear episodic response in contaminant load emitted from the river to the fjord. The main historic input to the fjord was found to be PAH from pyrogenic sources like coal and wood burning as well as traffic. A significant reduction in the level of PAH was observed since the 1980s. The measured flux of CPF is consistent with on-going societal use despite a ban on the use of short chain CPF imposed in Norway from 2002.publishedVersio
