Numerical hydrogeological modelling of drainage to an excavation

The report regards the conceptual and numerical modelling of drainage scenarios to a planned excavation in a deep clay deposit in Oslo, Norway. The modelling was performed in SEEP/W 2D. Ground investigations indicate that the clay lies directly on top of the bedrock, without a layer of moraine between them. The upper metres of the bedrock is assumed to be weathered and serve as a draining layer. The drainage of groundwater to the excavation along steel core piles, and the mitigating effect of cut-off walls of various lengths, were modelled. There were made several versions of the numerical model, with a variation of conductivity and upstream boundary conditions. The simulation results were compared with empirical pore pressure data presented by the R&D project BegrensSkade I (2012-2015). The simulation results deviated notably from the empirical data, leading to the conclusion that the model itself is unreliable. Although there were found weaknesses with the model that could have been improved and resulted in better compliance, some major uncertainties are considered to remain and to affect the results to a significant degree. The uncertainties are in particular related to the modelling of the (weathered) bedrock conductivity, i.e. how the groundwater flows horizontally, vertically and across large distances within the bedrock joints. The discussion of these uncertainties is only introductory, and there is first of all a need to study the literature in greater detail to find out whether these issues are as important as argued here, and whether researchers already have studied them sufficiently. If the literature study comes to the conclusion that more research is needed, two modelling tasks are proposed with the aim to get a better understanding of how the groundwater flow could have been modelled more realistically in a continuum two-dimensional model.Norges Forskningsråd Research Council of Norwa

ArcGIS-verktøy for å vurdere innlekkasjekrav og konsekvenser av tunnel i urbane områder

publishedVersio

Assessing potential building damage caused by leakage to urban tunnels

Building damage is a major risk for urban tunnelling. In areas with soft soil conditions, water ingress to bedrock tunnels can cause significant pore pressure reduction, consolidation settle-ments and damage to nearby buildings and infrastructure. In Norway, guidelines to determine leakage limits are based on a national database, containing data on water ingress, pore pressure reduction and influence zone. To support future projects, the database has been implemented into an ArcGIS-tool and merged with the Ground Impact and Building Vulnerability (GIBV) method to assess potential building damage at early project stages. This paper presents the adopted methodology and shows its application for a new subway tunnel in Oslo, Norway.Assessing potential building damage caused by leakage to urban tunnelsacceptedVersio

Deciphering long-term records of natural variability and human impact as recorded in lake sediments: a palaeolimnological puzzle

Global aquatic ecosystems are under increasing threat from anthropogenic activity, as well as being exposed to past (and projected) climate change, however, the nature of how climate and human impacts are recorded in lake sediments is often ambiguous. Natural and anthropogenic drivers can force a similar response in lake systems, yet the ability to attribute what change recorded in lake sediments is natural, from that which is anthropogenic, is increasingly important for understanding how lake systems have, and will continue to function when subjected to multiple stressors; an issue that is particularly acute when considering management options for aquatic ecosystems. The duration and timing of human impacts on lake systems varies geographically, with some regions of the world (such as Africa and South America) having a longer legacy of human impact than others(e.g. New Zealand). A wide array of techniques (biological, chemical, physical and statistical) is available to palaeolimnologists to allow the deciphering of complex sedimentary records. Lake sediments are an important archive of how drivers have changed through time, and how these impacts manifest in lake systems. With a paucity of ‘real‐time’ data pre‐dating human impact, palaeolimnological archives offer the only insight into both natural variability (i.e. that driven by climate and intrinsic lake processes) and the impact of people. Whilst there is a need to acknowledge complexity, and temporal and spatial variability when deciphering change from sediment archives, a palaeolimnological approach is a powerful tool for better understanding and managing global aquatic resources

3. Vers une homogénéisation des identités professionnelles des journalistes ?

Depuis ses débuts, le journalisme évolue en tant que champ masculin, dans son contenu aussi bien que dans ses idéaux et ses normes professionnelles. Au XXe siècle, le journalisme s’est construit en relation avec l’espace public, en traitant de sujets d’intérêt masculins et en s’appuyant sur des détenteurs du pouvoir (masculins) comme sources. La professionnalisation accrue du champ journalistique ne s’est pas opposée à cette logique, elle a même plutôt renforcé des éléments tels que la valeur..

Journalism in Transition. The professional Identity of Swedish Journalists

Is journalism going through ‘de-professionalization’ or is it just entering a new phase – taking a different shape? And what is the meaning of professional ideals such as scrutiny and autonomy in these processes? In my thesis, “Journalism in Transition”, I discuss these matters, focusing on the case of Swedish journalists. Empirical support is drawn from a national survey conducted five times since 1989 on the Dept. of Journalism, Media and Communication at the University Gothenburg (JMG). Questions about journalists’ perceptions of various ideals offer excellent opportunities to explore possible homogenization vs. fragmentation, and what the attitudinal dimensions actually say about the professional content of Swedish journalism. The results are analyzed by the conceptualization of Bourdieu’s field theory, along with current professional theory, and point at a possible separation of professional levels where a few ideals constitute an over-arching professional identity, while the flora of attitudes below is more diverse and dependent on factors of organizational affiliation, gender and age. Professional ideals may furthermore be regarded as a form of symbolic capital, used as legitimizing tools in journalism’s struggle for maintaining status quo. A main conclusion is that journalism is not de-professionalizing on ideological level, but going through a re-formation. Traditional journalistic ideals have attained increasing support over time and the efforts to fix professional boundaries are fierce. These boundaries are, however, subjects of negotiation: In the professional identity formation of Swedish journalists between 1989-2005 I also detect and increasing orientation towards liberal- and market values, which I interpret as the incorporation of organizational values into the professional identity – thereby legitimizing those. A second conclusion is that social attributes such as gender, age and formal qualifications mean less to the professional identity formation in 2005 than they did in 1989. The reason for this is the increasing homogenization of journalistic ideals – all journalists think increasingly alike, no matter social background. Factors still being highly relevant, though, are gender, journalistic training and place of work. Those factors determine journalists’ positions in the field and consequently form their professional identities into various shapes