Life cycle assessment as a decision support tool for bridge procurement: environmental impact comparison among five bridge designs
2014 (English)In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 19, no 12, 1948-1964 p.Article in journal (Refereed) Published
The conventional decision-making for bridges is mostly focusing on technical, economical, and safety perspectives. Nowadays, the society devotes an ever-increased effort to the construction sector regarding their environmental performance. However, considering the complexity of the environmental problems and the diverse character of bridges, the related research for bridge as a whole system is very rare. Most existing studies were only conducted for a single indicator, part of the structure components, or a specific life stage. Life Cycle Assessment (LCA) is an internationally standardized method for quantifying the environmental impact of a product, asset, or service throughout its whole life cycle. However, in the construction sector, LCA is usually applied in the procurement of buildings, but not bridges as yet. This paper presents a comprehensive LCA framework for road bridges, complied with LCA ReCiPe (H) methodology. The framework enables identification of the key structural components and life cycle stages of bridges, followed by aggregation of the environmental impacts into monetary values. The utility of the framework is illustrated by a practical case study comparing five designs for the Karlsnas Bridge in Sweden, which is currently under construction. This paper comprehensively analyzed 20 types of environmental indicators among five proposed bridge designs, which remedies the absence of full spectrum of environmental indicators in the current state of the art. The results show that the monetary weighting system and uncertainties in key variables such as the steel recycling rate and cement content may highly affect the LCA outcome. The materials, structural elements, and overall designs also have varying influences in different impact categories. The result can be largely affected by the system boundaries, surrounding environment, input uncertainties, considered impact indicators, and the weighting systems applied; thus, no general conclusions can be drawn without specifying such issues. Robustly evaluating and ranking the environmental impact of various bridge designs is far from straightforward. This paper is an important attempt to evaluate various designs from full dimensions. The results show that the indicators and weighting systems must be clearly specified to be applicable in a transparent procurement. This paper provides vital knowledge guiding the decision maker to select the most LCA-feasible proposal and mitigate the environmental burden in the early stage.
Place, publisher, year, edition, pages
2014. Vol. 19, no 12, 1948-1964 p.
Sustainable construction, Life cycle assessment, LCA, LCA for bridges, Global warming, Bridge, Carbon footprint, Environment, CO2 emission
Environmental Management Infrastructure Engineering Construction Management Environmental Analysis and Construction Information Technology
Research subject Civil and Architectural Engineering; Järnvägsgruppen - Infrastruktur
IdentifiersURN: urn:nbn:se:kth:diva-142919DOI: 10.1007/s11367-014-0797-zISI: 000344785900005ScopusID: 2-s2.0-84922073703OAI: oai:DiVA.org:kth-142919DiVA: diva2:704994
QC 201412152014-03-132014-03-132015-03-11Bibliographically approved