Sustainable Restoration Criteria for a Historical Steel Railway Bridge

摘要

The present paper briefly describes a methodology to evaluate the sustainability of existing steel bridges. This method applied to the case study for the restoration design of the old steel Echedoros river railway bridge. An intervention on an existing bridge characterized as sustainable if the design considerations include critical sustainability assessments. The present case study also compared to other relevant assessments of the option to construct a new steel bridge for the same total span. Assessments concern remaining fatigue life, estimation of its structural resistance for the traffic capacity, identification of the environmental impacts of the structural solutions and evaluation of the total cost of the project. In the present work, the structural analysis performed using a finite element scheme for the overall bridge. In addition, several finite element analysis models of critical details also performed and studied. The verification of the design parameters adopted, i.e. loads and resistance assessment mainly based on the 'Sustainable Bridges' guidelines recently published by the European Commission. The estimation of the environmental impacts of the structural solutions according to life cycle principles based on the use of known LCA tools and the cost evaluated by applying the well-known discounted cash flow technique. The approach with the individual impacts combined to produce an overall sustainability score for the design option also highlighted. This way, the proposed methodology leads to a more accurate assessment of the sustainability of an existing steel bridge.