| 1. |
- Enochsson, Ola, et al.
(författare)
-
Assessment and condition monitoring of a concrete railway bridge in Kiruna, Sweden
- 2006
-
Ingår i: Bridge maintenance, safety, management, life-cycle performance and cost. - London : Taylor and Francis Group. - 0415403154
-
Konferensbidrag (refereegranskat)abstract
- A two-span railway concrete trough bridge over Luossajokk in Kiruna in northern Sweden has been studied. The owner wanted to increase the axle loads from 250 to 300 kN in order to reduce freight costs for iron ore. Examples are given of methods used and results obtained from the assessment where bending, shear and fatigue were studied. Material properties, loads and load carrying capacity were evaluated using deterministic and probabilistic methods. It was shown that the bridge could carry the higher loads with a safety index β > 4.7 for reasonable assumptions of the load distributions. A measurement system was installed to check the actual level of critical strains and the worst positions of the train. Results are also given from a condition monitoring program 2001-2006, launched to periodically check the development of strains with time.
|
|
| 2. |
- Bagge, Niklas, 1987-, et al.
(författare)
-
Assessment of concrete bridges - Prestress forces : Experiences from full-scale testing to failure of a bridge in Kiruna
- 2017
-
Ingår i: Proceedings of the 23rd Nordic Concrete Research Symposium, Oslo, Norway: Nordic Concrete Federation. - Oslo : Nordic Concrete Federation. ; , s. 267-270
-
Konferensbidrag (refereegranskat)abstract
- To calibrate methods for condition assessment of prestressed concrete (PC) bridges, tests were carried out on a 55 year old five-span bridge with a length of 121 m in Kiruna in northern Sweden. Both non-destructive and destructive full-scale tests were performed. This paper presents results regarding the residual forces in the prestressed reinforcement.
|
|
| 3. |
- Bell, Brian, et al.
(författare)
-
Sustainable Bridges – Past and Future. Reflections on a European Project 2003 – 2007
- 2023
-
Ingår i: IABSE Congress 2023 New Delhi, Engineering for Sustainable Development. - : International Association for Bridge and Structural Engineering. ; , s. 690-698
-
Konferensbidrag (refereegranskat)abstract
- Twenty years ago, in 2003, a European project was started to increase the sustainability of existing railway bridges. This paper summarises what was achieved and looks ahead. Nine Working Packages were organized: (1) Background material; (2) Guidance by stakeholders; (3) Condition Assessment and Inspection Guidelines; (4) Loads, Capacity and Resistance Guidelines; (5) Monitoring Guidelines; (6) Repair and Strengthening Guidelines; (7) Demonstration with Field testing of Bridges; (8) Demonstration on Monitoring on Bridges; and (9) Training and Dissemination.Some of the main results (from 4 Guidelines and 47 Background documents) are highlighted and some experiences, conclusions and thoughts about the future are given. Hidden strengths and weaknesses are discussed, analyses and codes for assessment can be improved, new monitoring and strengthening methods are available and life length can be prolonged.
|
|
| 4. |
- Blanksvärd, Thomas, et al.
(författare)
-
Test to failure of a steel truss bridge – Calibration of assessment methods
- 2014
-
Ingår i: Bridge Maintenance, Safety, Management and Life Extension. - London : CRC Press, Taylor & Francis Group. - 9781138001039 - 9781315760698 ; , s. 1076-1081
-
Konferensbidrag (refereegranskat)abstract
- The steel truss railway bridge at Åby River was built in 1957 with a span of 32 m (105 feet). In 2012 it was replaced by a new steel beam bridge and the old bridge was placed beside the river. It was tested to failure to study its remaining load-carrying capacity in September 2013. The test was carried out by Luleå University of Technology by commission from Trafikverket as a part of the European Research Project MAINLINE (www.mainline-project.eu). In this paper some preliminary results are given. Two hydraulic jacks, anchored by cables to the bedrock, pulled the bridge downwards. The bridge remained elastic up to about three times the original design load and the load could then be almost doubled with substantial yielding deformations before a buckling failure appeared in the top girders for a load of ca. 11 MN (1000 short tons) for a midpoint deflection of ca. 0, 2 m (8 inches). No brittle or fatigue failure in any of the joints appeared and the bridge proved to behave in a ductile way with a substantial hidden capacity.
|
|
| 5. |
- Elfgren, Lennart, 1942-, et al.
(författare)
-
Load-testing used for quality control of bridges
- 2018
-
Ingår i: Quality Specifications for Roadway Bridges. ; , s. 1-6
-
Konferensbidrag (refereegranskat)abstract
- Load testing is a way to control the capacity and function of a bridge. Methods and recommendations for load testing are described and examples are given form tests carried out. In order not to damage the bridge being tested, the load must be limited, often to be within the serviceability limit state (SLS). Numerical models can be calibrated by load tests and then be used to check the carrying capacity for higher loads than what has been tested. Need for further work and recommendations are discussed. By effective planning costs can be saved and a more sustainable use of bridges can be obtained.
|
|
| 6. |
- Elfgren, Lennart, et al.
(författare)
-
Sustainable railway bridges with higher axle loads : monitoring examples from northern Sweden
- 2007
-
Ingår i: High Tech in Heavy Haul. - Luleå : Luleå tekniska universitet. - 9789163306075 ; , s. 159-166
-
Konferensbidrag (refereegranskat)abstract
- Monitoring of several railway bridges has been carried out in northern Sweden in order to increase the allowable axle load. The work is part of a European Integrated Project "Sustainable Bridges - Assessment for Future Traffic Demands and Longer Lives". The paper describes the project and gives some examples of applications.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Nilimaa, Jonny, 1986-, et al.
(författare)
-
Assessment and Loading to Failure of Three Swedish RC Bridges
- 2018
-
Ingår i: Evaluation of Concrete Bridge Behavior through Load Testing. - Faarmington Hills, MI : American Concrete Institute. - 9781641950077 ; , s. 8.1-8.18
-
Bokkapitel (refereegranskat)abstract
- Current codes often underestimate the capacity of existing bridges. The purpose of the tests presented here has been to assess the real behaviour and capacity of three types of bridges in order to be able to utilize them in a more efficient way.The three studied bridges are: (1) Lautajokk – A one-span trough bridge tested in fatigue to check the shear capacity of the section between the slab and the girders; (2) Övik – A two span trough bridge strengthened with Near Surface Mounted Reinforcement (NSMR) of Carbon Fibre Reinforced Polymers (CFRP) tested in bending, shear and torsion; and (3) Kiruna – A five-span prestressed three girder bridge tested to shear-bending failures in the girders and in the slab.The failure capacities were considerably higher than what the code methods indicated. With calibrated and stepwise refined finite element models, it was possible to capture the real behaviour of the bridges. The experiences and methods may be useful in assessment and better use of other bridges.
|
|
| 10. |
- Nilimaa, Jonny, et al.
(författare)
-
Extend the life of existing railway bridges : Results from EU FP7 project MAINLINE
- 2015
-
Ingår i: IABSE Conference Geneva 2015. - Geneva : International Association for Bridge and Structural Engineering. - 9783857481406 ; , s. 1219-1226
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- There is a need to extend the life and capacity of many existing bridges. One of the objects of the EU FP7 Project MAINLINE, 2011-2014, was to facilitate this. Guidelines for assessment and strengthening methods are presented as well as case studies in which existing bridges are studied in order to extend their life length. One example is the prestressing of the slab in a one-span concrete trough bridge in order to increase its load-carrying capacity. Horizontal holes were drilled trough the slab and in them steel bars were placed and post-tensioned. In this way a compressive stress was introduced into the concrete section so that it’s bending and shear capacity was increased.In another study a metal truss bridge was monitored in order to check strain and stress ranges in critical connections to enable an enhanced evaluation of the remaining fatigue resistance. The studied bridge was then replaced and loaded to failure to study its robustness and the reliability of applied assessment methods. The results could then be applied to prolong the life of an identical twin bridge located in the northern part of Sweden. A Life Cycle Assessment Tool (LCAT) has been developed to enable Infrastructure Managers to choose optimal maintenance strategies.
|
|
