11. |
- Bhanbhro, Riaz, et al.
(författare)
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Mechanical Properties and Particle Breakage of Uniform-Sized Tailings Material
- 2021
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Ingår i: Journal of materials in civil engineering. - Luleå : American Society of Civil Engineers (ASCE). - 0899-1561 .- 1943-5533. ; 33:3
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Tidskriftsartikel (refereegranskat)abstract
- Tailings dam disasters are reported almost every year and are triggered by mechanisms, such as overtopping, piping, and others.The failures due to inadequate management cannot be neglected as well. These dams are constructed mostly in a step-by-step constructionmethod that leads to a continuously changing state of vertical loads during construction and may lead to particle breakage and changes instrength. Therefore, a layer of tailings dam today may not be the same tomorrow during the construction phase. To study the effects ofdifferent loads on particle breakage and strength, direct shear tests were performed on remolded tailings samples that were separated intodifferent particle sizes. The tests were performed using different normal stresses that ranged from 50 to 500 kPa. The results indicate that finertailings exhibited slightly more shear resistance than that of coarser tailings irrespective of the deposition method. For normally depositedspecimen, the dilatant and contractant behavior in vertical height was observed when the normal effective stress was less than 300 kPa andgreater than 300 kPa, respectively. Under the vertical deposition method, the finer tailings showed contractant height behavior when subjectedto a normal effective stress of 300 kPa. The friction angle and the cohesion of vertically deposited specimens were slightly higher and slightlylower, respectively, than that of normally deposited ones. The breakage of tailings particles was observed to be proportional to the particle sizeof the tailings.
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12. |
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13. |
- Dahlberg, Anders, et al.
(författare)
-
786 svampar på 2015 års rödlista
- 2015
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Ingår i: Svensk Mykologisk Tidskrift. - 1653-0357. ; 36, s. 91-97-
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- A new Swedish Red List was published April 28th 2015 by the Swedish Species Information Centre in which 786 species of fungi are listed. Compared to the previous Red List published in 2010, 11 species have been down-listed, 51 species have been added and 35 species have changed names or taxonomic rank, thus the list has increased by 41. The changes are mainly due to increased knowledge of taxonomy, ecology and distribution, not to changes in the sta-tus of the species. Here, the members of the Species Specialist Group for Fungi 2011 – 2015 summarize the results of the red listing.
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14. |
- Dahlberg, Anders, et al.
(författare)
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Den nya rödlistan har 746 svampar
- 2010
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Ingår i: Svensk mykologisk tidskrift. - 1653-0357. ; 31:2, s. 37-47
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Tidskriftsartikel (refereegranskat)abstract
- The new Red List that was recently presented by the Swedish Species Information Centre (Gärdenfors 2010) includes 746 species of fungi considered to be threatened. Compared to the previous Red List published in 2005, 36 species have been down-listed whereas 150 species have been added, thus the list has increased by 114. The changes are above all due to increased knowledge of taxonomy, ecology and distribution. In the present paper members of the Species Specialist Group for Fungi 2006-2010 summarize the background and results of the red-listing process and present the habitats in which the red-listed species occur.
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15. |
- Dahlberg, Anders, et al.
(författare)
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Svampar – Fungi
- 2010
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Ingår i: Rödlistade arter i Sverige 2010 – The 2010 Red List of Swedish Species. - 9789188506351 ; , s. 231-246
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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16. |
- Dahlberg, Anders, et al.
(författare)
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Svampar Fungi
- 2020
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Ingår i: Rödlistade arter i Sverige 2020. - 9789187853548 ; , s. 67-88
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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17. |
- Dahlberg, Anders, et al.
(författare)
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Svampar Fungi
- 2015
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Ingår i: Rödlistade arter i Sverige 2015. - 9789187853104 ; , s. 53-71
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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18. |
- Edeskär, Tommy, et al.
(författare)
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Grundläggning av vindkraftverk med hänsyn till tjäle
- 2010
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Ingår i: Bygg och Teknik. - 0281-658X .- 2002-8350. ; 102:1, s. 68-73
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- På grund av den snabba utbyggnaden av vindkraftverk är erfarenheten från byggande i kallt klimat för dessa konstruktioner begränsad. Den forskning som bedrivs idag är mestadels inriktad mot vindkraftens miljöpåverkan samt frågor för att underlätta utbyggnaden och förbättra kostnadseffektiviteten, Statens energimyndighet (2008). Utbyggnad av vindkraftverk i extrema miljöer skapar nya frågor som bör utredas för att säkerställa verkens kvalitet i ett långtidsperspektiv. I denna artikel vill vi belysa frågan om tjäle och hur den är kopplad till grundläggning av vindkraftverk.
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19. |
- Edeskär, Tommy, et al.
(författare)
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Numerical analysis of frost penetration around footings of power mills in subarctic conditions
- 2009
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Ingår i: Proceedings of the 20th International Conference on Port and Ocean Engineering under Arctic Conditions.
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Konferensbidrag (refereegranskat)abstract
- The potential for establishing wind power farms in the subarctic areas is high due to the combination of large available areas and few conflicting interests. In subarctic climate frost and thaw are major principal design aspects. In foundation work the major impact of frost action is at the outer peripheries of the foundation. Therefore most analysis work and prevention actions such as insulation around the foundation are concentrated to this part of the structure. The gravity foundations of wind power plants are often constructed as a reinforced concrete monolite. In the centre of the footing a steel cage is attached for anchoring the wind mill tower. This steel cage ends close to the sub-grade and can due to considerably higher thermal conductivity, compared to the concrete structure, transport a lot more heat. By FEM analysis, the frost penetration around, and under two typical wind-power foundations have been analyzed for different climate conditions in Sweden. In addition, different soil types have also been used. The result shows that the frost penetration in the centre of the foundation needs to be considered. Further it is shown that it is larger in the centre than compared to the periphery.
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20. |
- Edeskär, Tommy, et al.
(författare)
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Use of scrap tyres as insulation layer in road construction
- 2007
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Ingår i: Proceedings of the 8th International Symposium on Cold region Development ISCORD 2007. - : RIL - Finnish Association of Civil Engineers.
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Konferensbidrag (refereegranskat)abstract
- Used tyres are not allowed to be placed on landfills any more, but can be used as insulation materials with very good results. The present paper describes a study in which tyre shreds (50mm * 50 mm) were used as insulation material in a road construction. The tyre shreds had a thickness of 600 mm and were covered with 875 mm of road superstructure. The effect of the layer on frost depth and frost heave was measured during three winters. As scrap tyres are a highly elastic the bearing capacity and Young's module were measure directly on the road by the use of a falling weight deflectometer. The potential environmental impact was also studied. The scrap tyres showed a very good insulation performance, mostly due to its high porosity. Effects of frost action were not visible or recorded. The studied construction had deformation pattern of the road surface was within acceptable limits. The environmental impact was studied before the pavement was placed at the top and therefore leakage could be detected.
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