Retrofitting of damaged bridges – the sustainable solution

다국어 초록 (Multilingual Abstract)

Rehabilitation of damaged bridges may be more beneficial than building new bridges. However, proper methods are necessary to assess the level of damages and to verify the fitness of such bridges for further use. In the assessment, there are two important criteria to consider. One is the amount of damage due to fatigue caused by usual past vehicle loading and the other is the magnitude of damage caused by the unexpected actions. The present paper is about a wrought iron bridge damaged by floods.
In order to do the assessment, a condition survey was first carried out. Then an analysis was done using a finite element model of the bridge. The model was validated using results of a field loading test. Both static and dynamic loading tests were conducted using a locomotive with six numbers of 13.16-ton axles for five different loading cases to measure the displacement, strain and acceleration at predetermined (critical) members of the bridge. Then the damage in the bridge due to past loading histories and the future fatigue life of the bridge were estimated.
Furthermore, using the validated model, the ability of the bridge for higher loading situations was confirmed. The future life was found as 30 years with a factor of safety of 3. The cost estimated for retrofitting work and constructing new reinforced concrete abutments was much less than that for constructing a new bridge. Therefore, it was decided that the rehabilitation of the bridge with necessary retrofitting work is more economical and sustainable than demolishing it and constructing a new one. The bridge is now in use after being repaired, retrofitted and placed on new abutments.

참고문헌 (Reference)

1 Bandara, C. S., "The impact of the gigacycle fatigue on steel bridges" 569 (569): 246-253, 2013

2 Norio, O., "The 2011 eastern Japan great earthquake disaster: Overview and comments" 2 (2): 34-42, 2011

3 Drexhage, J., "Sustainable development: from Brundtland to Rio 2012" United Nations Headquarters 2010

4 Siriwardane, S. A. S. C., "Structural appraisal based different approach to estimate the remaining fatigue life of railway bridges" 9 (9): 323-339, 2010

5 Dissanayake, P. B. R., "Risk assessment and retrofitting methodology, assessment report of bridge no.02 at Puttalam" University of Peradeniya 2011

6 Dias, P., "Lessons learnt from tsunami damages in Sri Lanka" 159 : 74-81, 2006

7 Dissanayaka, P. B. R., "Investigation report of bridge no. 02" University of Peradeniya 2012

8 "EN 1993. Design of steel structures, Part 1–9: Fatigue"

9 "EN 1991. Action on structures, Part – 2: Traffic loads on bridges"

10 "District Line Fatigue of Riveted Under Bridges"

11 Siriwardane Sudath Chaminda, "Different Approaches for Remaining Fatigue Life Estimation of Critical Members in Railway Bridges" 한국강구조학회 7 (7): 263-276, 2007

12 Bandara, C. S., "Developing a full range S–N curve and estimating cumulative fatigue damage of steel elements" 96 : 96-101, 2015

13 "BS 5400, Part 10. Code of practice for fatigue, steel concrete and composite bridges"

14 "BS 3518. Methods of fatigue testing: Part 2: Rotating bending fatigue test"

15 "ASTME 8M– 01. Standard test Method for Tension Testing of Metallic Materials, American Society for Testing Materials"

16 "ASTM E 18–02. Standard test methods for Rockwell hardness and Rockwell superficial hardness of metallic materials, American Society for Testing Materials"

17 Karunananda, K., "A combined high and low cycle fatigue model to estimate life of steel bridges" 2 (2): 144-160, 2010