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Knutsson, S., Tommik, K., Bansal, T. & Motamedi, Z. (2024). Tjäle och tjälforskning vid Luleå tekniska universitet. Bygg & teknik (1)
Open this publication in new window or tab >>Tjäle och tjälforskning vid Luleå tekniska universitet
2024 (Swedish)In: Bygg & teknik, ISSN 0281-658X, no 1Article in journal (Other academic) Published
Abstract [sv]

Tjäldjup, tjällyftningar och tjällossningsproblem är årligen återkomman­de fenomen, som inträffar när jordmaterial fryser och tinar. I Sverige är frysningen säsongsmässig, med relativt korta vintrar i söder och upp till sex månader långa i norra Sverige. Tjällossningen sker under våren och avslutas i norra Sverige först vid midsommartid och är inte sällan förknippad med att vägars bärförmåga kan påverkas negativt. Tjäldjupet ökar successivt under vintern med mer eller mindre ojämn tjällyftning som följd. Graden av tjällyftning beror av temperatur i uteluft, jordmaterial och tillgång på vatten. Just ojämnhet i tjällyftningar för vägar och järnvägar är ett problem då det påverkar såväl komfort som säkerhet. Ojämna tjällyftningar behandlas för närvarande i tre olika doktorandprojekt vid LTU och dessa beskrivs här.

Place, publisher, year, edition, pages
Byggteknikförlaget, 2024
National Category
Infrastructure Engineering Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-104156 (URN)
Funder
Swedish Transport Administration
Available from: 2024-02-02 Created: 2024-02-02 Last updated: 2024-02-02Bibliographically approved
Tommik, K., Knutsson, S., Laue, J. & Lintzén, N. (2023). Air velocity and temperature distribution in culverts. Cold Regions Science and Technology, 212, Article ID 103888.
Open this publication in new window or tab >>Air velocity and temperature distribution in culverts
2023 (English)In: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 212, article id 103888Article in journal (Refereed) Published
Abstract [en]

Uneven frost heave in roads and railways is a frequent problem in cold regions leading to degradation of structures. To improve drainage, culverts are frequently integrated into road and railway embankments. The presence of culverts changes the temperature distribution in the surrounding soil as cold air passes through the culvert. Consequently, frost depth and corresponding frost heave are increased in the vicinity of the culvert compared to the rest of the structure if frost susceptible soil is present. For an accurate frost related design, information of heat balance between the culvert and the surrounding soil is needed. A field study focusing on convective heat transfer in culverts was conducted in northern Sweden by the authors. Temperatures and air velocities in culverts of three sizes (0.6, 0.8 and 3.4 m) were recorded. Analysis of obtained data is presented in this paper with emphasis on the influence of air velocity on the temperature distribution. Influence of wind on development of airflow in culverts is also addressed. Accuracy of trained gaussian process regression (GPR) models is estimated in predicting temperature distribution inside of culverts. It is concluded, based on the field measurement data, that airflow can significantly affect temperature distribution inside culverts and development of airflow in culverts is largely influenced by the orientation of the culvert in relation to the predominant wind direction.

Place, publisher, year, edition, pages
Elsevier, 2023
Keywords
Air flow, Cold climate, Culvert, Seasonally frozen ground
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-97692 (URN)10.1016/j.coldregions.2023.103888 (DOI)001008399000001 ()2-s2.0-85159163586 (Scopus ID)
Funder
Swedish Transport Administration
Note

Validerad;2023;Nivå 2;2023-06-02 (hanlid)

Available from: 2023-06-02 Created: 2023-06-02 Last updated: 2024-03-07Bibliographically approved
Wiklund, V., Knutsson, R., Laue, J., Knutsson, S. & Häggström, H. (2023). Towards better understanding of CPT data on tailings. In: : . Paper presented at 91st Annual ICOLD Meeting, June 13-14, 2023, Gothenburg, Sweden.
Open this publication in new window or tab >>Towards better understanding of CPT data on tailings
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2023 (English)Conference paper, Published paper (Other academic)
Abstract [en]

Characterization of tailings deposits is associated with significant challenges in tailings dam design and dam safety assessments. One of the challenges is static liquefaction in the deposited tailings and how this has to be addressed in stability assessments. Concerns have led to design concepts that deposited tailings considered susceptible to liquefaction, will liquefy. Facillities should therefore be designed for such post-liquefaction scenario, i.e. fluidized tailings. Existing upstream-constructed tailings dams are seldom built for a design case with post-liquefaction strength in the tailings. Consequently, mining companies must take dam safety-enhancing measures and rapidly conduct major changes in their tailings dam design.

At the same time, there are questions and uncertainties in evaluating static liquefaction potential in tailings that must be addressed. The uncertainties are, among others, related to differences between natural sands and tailings. There is a need to address the applicability of today’s evaluation methods on tailings and this paper will describe how a research project at Luleå University of Technology, funded by Boliden, will investigate and address the uncertainties in the evaluation. Cone Penetration Testing (CPT) in a calibration chamber will be undertaken in the project. A new calibration chamber for CPT is developed, where silty-sandy tailings material will be tested in a controlled laboratory environment. Combined with other laboratory test results, the CPT calibration chamber results will be used to derive new and update existing correlations between CPT data and tailings properties. The research will focus on the mechanical properties of tailings and its influence on the soil behavior around the penetrating cone. This paper will highlight uncertainties in state interpretation from CPT in tailings, present the design work of the calibration chamber and the expectations for the outcome of the CPT calibration chamber research.

National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-103821 (URN)
Conference
91st Annual ICOLD Meeting, June 13-14, 2023, Gothenburg, Sweden
Note

Funder: Boliden Mineral AB

Available from: 2024-01-18 Created: 2024-01-18 Last updated: 2024-02-05Bibliographically approved
Bansal, T., Knutsson, S. & Laue, J. (2022). Forensic Investigations of the old E10 road in Kiruna, Sweden: [Enquête médico-légale de l'ancienne route E10 à Kiruna, Suède]. In: M. Rahman; M. Jaksa (Ed.), Proceedings of the 20th International Conference on Soil Mechanics and Geotechnical Engineering: . Paper presented at 20th International Conference on Soil Mechanics and Geotechnical Engineering 2022 (ICSMGE 2022), Sydney, Australia, May 1-5 2022 (pp. 4481-4485). Australian Geomechanics Society
Open this publication in new window or tab >>Forensic Investigations of the old E10 road in Kiruna, Sweden: [Enquête médico-légale de l'ancienne route E10 à Kiruna, Suède]
2022 (English)In: Proceedings of the 20th International Conference on Soil Mechanics and Geotechnical Engineering / [ed] M. Rahman; M. Jaksa, Australian Geomechanics Society , 2022, p. 4481-4485Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Australian Geomechanics Society, 2022
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-84812 (URN)
Conference
20th International Conference on Soil Mechanics and Geotechnical Engineering 2022 (ICSMGE 2022), Sydney, Australia, May 1-5 2022
Projects
Make Way for Future (Bana och Väg För Framtiden – BVFF)
Funder
Swedish Transport Administration
Note

ISBN för värdpublikation: 978-0-9946261-4-1

Available from: 2021-06-01 Created: 2021-06-01 Last updated: 2023-07-06Bibliographically approved
Tommik, K., Knutsson, S., Laue, J. & Lintzén, N. (2022). Heat flow and temperatures in three culverts embedded in road embankments subjected to seasonal frost: [Flux de chaleur et températures dans trois ponceaux routiers soumis au gel saisonnier]. In: M. Rahman; M. Jaksa (Ed.), Proceedings of the 20th International Conference on Soil Mechanics and Geotechnical Engineering: . Paper presented at 20th International Conference on Soil Mechanics and Geotechnical Engineering 2022 (ICSMGE 2022), Sydney, Australia, May 1-5, 2022 (pp. 3987-3991). Australian Geomechanics Society
Open this publication in new window or tab >>Heat flow and temperatures in three culverts embedded in road embankments subjected to seasonal frost: [Flux de chaleur et températures dans trois ponceaux routiers soumis au gel saisonnier]
2022 (English)In: Proceedings of the 20th International Conference on Soil Mechanics and Geotechnical Engineering / [ed] M. Rahman; M. Jaksa, Australian Geomechanics Society , 2022, p. 3987-3991Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Australian Geomechanics Society, 2022
National Category
Geotechnical Engineering Infrastructure Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-99175 (URN)
Conference
20th International Conference on Soil Mechanics and Geotechnical Engineering 2022 (ICSMGE 2022), Sydney, Australia, May 1-5, 2022
Projects
BVFF
Funder
Swedish Transport Administration
Note

ISBN för värdpublikation: 978-0-9946261-4-1

Available from: 2023-07-06 Created: 2023-07-06 Last updated: 2023-09-05Bibliographically approved
Tommik, K., Knutsson, S., Laue, J. & Lintzén, N. (2022). Influence of air flow on temperature distribution in culverts, measurements versus prediction: [Influence du débit d'air sur la distribution de la température dans les buses, mesures versus prédiction]. In: B. Scott (Ed.), Proceedings of the 7th International Young Geotechnical Engineers Conference: . Paper presented at 7th International Young Geotechnical Engineers Conference (7iYGEC 2022), Sydney, Australia, April 29 - May 1, 2022 (pp. 495-498). Australian Geomechanics Society
Open this publication in new window or tab >>Influence of air flow on temperature distribution in culverts, measurements versus prediction: [Influence du débit d'air sur la distribution de la température dans les buses, mesures versus prédiction]
2022 (English)In: Proceedings of the 7th International Young Geotechnical Engineers Conference / [ed] B. Scott, Australian Geomechanics Society , 2022, p. 495-498Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Australian Geomechanics Society, 2022
National Category
Infrastructure Engineering Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-99182 (URN)
Conference
7th International Young Geotechnical Engineers Conference (7iYGEC 2022), Sydney, Australia, April 29 - May 1, 2022
Projects
BVFF
Funder
Swedish Transport Administration
Note

ISBN för värdpublikation: 978-0-9946261-5-8

Available from: 2023-07-07 Created: 2023-07-07 Last updated: 2023-09-05Bibliographically approved
Toromanovic, J., Mattsson, H., Knutsson, S., Laue, J. & Bernstone, C. (2022). Mechanical behaviour of an experimental embankment dam during initial impoundment: [Comportement mécanique d'un barrage en remblai expérimental lors de la mise en eau initiale]. In: M. Rahman; M. Jaksa (Ed.), Proceedings of the 20th International Conference on Soil Mechanics and Geotechnical Engineering: . Paper presented at 20th International Conference on Soil Mechanics and Geotechnical Engineering 2022 (ICSMGE 2022), Sydney, Australia, May 1-5, 2022 (pp. 1217-1222). Australian Geomechanics Society
Open this publication in new window or tab >>Mechanical behaviour of an experimental embankment dam during initial impoundment: [Comportement mécanique d'un barrage en remblai expérimental lors de la mise en eau initiale]
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2022 (English)In: Proceedings of the 20th International Conference on Soil Mechanics and Geotechnical Engineering / [ed] M. Rahman; M. Jaksa, Australian Geomechanics Society , 2022, p. 1217-1222Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Australian Geomechanics Society, 2022
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-92606 (URN)
Conference
20th International Conference on Soil Mechanics and Geotechnical Engineering 2022 (ICSMGE 2022), Sydney, Australia, May 1-5, 2022
Funder
Energy ResearchLuleå University of TechnologyKTH Royal Institute of TechnologyChalmers University of TechnologyUppsala UniversityLund University
Note

Funder: Swedish Hydropower Centre - SVC

ISBN för värdpublikation: 978-0-9946261-4-1

Available from: 2022-08-22 Created: 2022-08-22 Last updated: 2023-07-06Bibliographically approved
Toromanovic, J., Mattsson, H., Laue, J. & Knutsson, S. (2021). A Non-Destructive Parameter Identification for an Embankment Dam. In: Gabriella Bolzon, Donatella Sterpi, Guido Mazzà, Antonella Frigerio (Ed.), Numerical Analysis of Dams: Proceedings of the 15th ICOLD International Benchmark Workshop. Paper presented at 15th ICOLD International Benchmark Workshop, 9-11 September, 2019, Milano, Italy (pp. 889-899). Springer Nature
Open this publication in new window or tab >>A Non-Destructive Parameter Identification for an Embankment Dam
2021 (English)In: Numerical Analysis of Dams: Proceedings of the 15th ICOLD International Benchmark Workshop / [ed] Gabriella Bolzon, Donatella Sterpi, Guido Mazzà, Antonella Frigerio, Springer Nature, 2021, p. 889-899Conference paper, Published paper (Refereed)
Abstract [en]

When performing predictions of future behaviour and assessments of the safety for embankment dams, numerical modelling if often needed as support. For embankment dams a usual issue is to obtain values of the material parameters for the material in the dam. Sampling is not easily performed, and it could also negatively affect the performance and safety of the dam. One way to determine values of the material parameters is to create a digital copy of the dam by utilizing so called inverse analysis. The created numerical model is calibrated towards field measurements. To make the reality and the numerical model correspond to each other, the values of material parameters for constitutive models are calibrated. The calibration is done by an automatized process. Further, the calibrated model could be used in predictions of future dam behaviour. The methodology has been shown to work for field data containing errors of a usual magnitude.

Place, publisher, year, edition, pages
Springer Nature, 2021
Series
Lecture Notes in Civil Engineering, ISSN 2366-2557, E-ISSN 2366-2565 ; 91
Keywords
Embankment dam, Inverse analysis, Digital twin, Predictions Noise
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-76459 (URN)10.1007/978-3-030-51085-5_51 (DOI)2-s2.0-85096621345 (Scopus ID)
Conference
15th ICOLD International Benchmark Workshop, 9-11 September, 2019, Milano, Italy
Note

ISBN för värdpublikation: 978-3-030-51084-8, 978-3-030-51085-5

Available from: 2019-10-21 Created: 2019-10-21 Last updated: 2022-06-30Bibliographically approved
Adamo, N., Al-Ansari, N., Sissakian, V., Laue, J. & Knutsson, S. (2021). Dam Safety: Hazards Created by Human Failings and Actions. Journal of Earth Sciences and Geotechnical Engineering, 11(1), 65-107
Open this publication in new window or tab >>Dam Safety: Hazards Created by Human Failings and Actions
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2021 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 11, no 1, p. 65-107Article in journal (Refereed) Published
Abstract [en]

Dam Safety and dam incidents are treated here looked at from the "Human Factors" perspective. An attempt is made to explore these factors as an important drive in impairing dams’ safety and increases their risks. Distinction is drawn between the "Normal Human Caused Incidents" and the "Extraordinary Human Caused Incidents" together with the description of their root origins and subsequent consequences. The first type includes unintentional mistakes, errors and flaws committed by the operators of dams inadvertently, in addition to negligence, lack of experience or overconfidence. Such failings can happen in manual operation of dams, or through the use of their Supervision, Control and Data Acquisition (SCADA) systems as in industrial control system (ICS). They can occur also due to flaws in software or even in the application of information and communication technology (ICT) in remote control operations. As for the second group; the extraordinary human factors, they are defined here as those committed by man with the full understanding of their possible damage. They are done purposely for destabilizing dams after thoughtful and carefully meditated decision making process and they are manifested in acts of war, sabotage and terrorists actions. In this modern age, these acts are characteristics of hackers’ attacks on dam(s) operating systems. This is done through the use of cyberspace by the widespread interconnected digital technology with the accompanying advances in the communication technologies. As such, these technologies have made remote control of such systems possible. Not limited to this, dams remain now, as they were always in the past, the obvious targets in wars and conflicts to inflict losses on the enemy and to use them as weapons, and for terrorism actions for challenging governments. Examples of the aforementioned threats are described with examples given from real cases to elucidate the dangers involved. Lessons to be learned from these incidents are derived and recommendations are presented to be followed to avoid risky situations.

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2021
Keywords
Normal human caused incidents, extraordinary human caused incidents, SCADA Systems, ICS System, software, ICT Technology, cyberspace, digital technology, remote control, hackers, terrorism
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-80953 (URN)10.47260/jesge/1113 (DOI)
Note

Validerad;2020;Nivå 1;2020-09-29 (johcin)

Available from: 2020-09-28 Created: 2020-09-28 Last updated: 2023-09-05Bibliographically approved
Adamo, N., Al-Ansari, N., Sissakian, V., Laue, J. & Knutsson, S. (2021). Dam Safety: Monitoring of Tailings Dams and Safety Reviews. Journal of Earth Sciences and Geotechnical Engineering, 11(1), 249-289
Open this publication in new window or tab >>Dam Safety: Monitoring of Tailings Dams and Safety Reviews
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2021 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 11, no 1, p. 249-289Article in journal (Refereed) Published
Abstract [en]

The awareness to tailings dam safety monitoring and reviews has increased by the catastrophes resulting from failures of such dams worsened by increasing tailings waste and construction of larger dams. The losses born by the mining industry from high costs of compensations and environmental rehabilitation work have brought this matter into focus. In the present article the need for safety monitoring programs of tailings dam is highlighted and mode of failures and factors leading to them are described. Basic principles of such programs are investigated with all phenomena needing observation described and their impacts explained. As in conventional dams this work is carried out by visual inspections and use of similar methods and instruments. In similar manners in both types of dams’ observation and measurements are done for measuring seepage water quantity and quality, phreatic surface level and pore pressure and total earth pressure values in addition to deformation measurements; and all are done by similar devices and methods such as weirs, piezometers, inclinometers, settlement plates and geodetic surveying. Basic differences between safety monitoring systems of the two types of dam, however, are presented in a tabular form. The continuity of safety monitoring of tailings dams is emphasized not only during the long construction phase but also after that in the abandonment and closure phase which can last indefinitely in order to watch for possible adverse effects on the environment and ecosystem due to the winds eroding and carrying of poisonous tailings contents, in addition to

contaminated seepage water entering surface water streams and ground water. Justifications for using real time monitoring systems for recording and transmitting all data to the control center are presented with emphasis given on savings in both labor and time and need for the discovery of warning signs enabling raising earlier the alarm of possible failure or incident and the early taking of preventive measures. In this article it is argued that, in spite of the large investment of installing and running cost of comprehensive dam safety monitoring systems in tailings dams, such costs are justified as they form only a small percentage of the total investment in the tailings facilities projects, and may save huge costs if failure does happen. Such systems may be considered as an additional insurance against such events.

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2021
Keywords
Tailings dam, safety monitoring, environment, ecosystem, visual inspections, instrumentation, deformation, seepage, phreatic surface, pore water pressure, total earth pressure, settlement, inclinometer
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-80957 (URN)10.47260/jesge/1117 (DOI)
Note

Validerad;2020;Nivå 1;2020-09-29 (johcin)

Available from: 2020-09-28 Created: 2020-09-28 Last updated: 2023-09-05Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-1365-8552

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