Assessing the life cycle costs and environmental performance of lightweight materials in automobile applications

Life cycle assessment (LCA) and manufacturing focused life cycle costing are used to evaluate the potential advantages of composites in automotive applications. The life cycle costs and environmental performance of several suitable lightweight polymer composites are quantified and compared against magnesium and steel for a representative component. The results indicate that weight reduction will not always lead to improved environmental performance. Materials offering high weight savings such as carbon fibres and magnesium have been shown to give limited or negative environmental benefits over their life cycles due to increased environmental burdens associated with their production. Lower performance materials such as sheet moulding compounds were found to perform better from a life cycle perspective despite not being recycled. Lighter weight vehicle components were found to be always more costly; however their use did lead to reduced costs for the consumer through lower fuel consumption. (C) 2011 Elsevier Ltd. All rights reserved.

Carbon Fibre Reinforced Composite Waste: An Environmental Assessment Of Recycling, Energy Recovery And Landfilling

Christian Ludwig, Jan-Anders Månson, Véronique Michaud, Rémy Teuscher, Robert Andrew Witik

The environmental benefits of recycling are assessed against other end-of-life (EOL) treatments for Carbon Fibre Reinforced Plastic (CFRP) waste. Recycling via pyrolysis, incineration with energy recovery, and disposal via landfilling are compared. To account for physical changes to materials from use and recycling, equivalence between recycled and virgin materials is calculated based on the ability to produce a short fibre composite beam of equivalent stiffness. Secondary effects of using Recycled Carbon Fibre (RCF) in a hypothetical automotive application are also analysed. Results underline the ecological constraints towards recycling CFRPs and demonstrate that benefits from recycling are strongly linked to the impacts of the selected recovery process, the materials replaced by RCF in a secondary application, and also to the type of secondary application in which they are used. (C) 2013 Elsevier Ltd. All rights reserved.

Elsevier2013

Life cycle environmental assessment of retaining walls in unsaturated soils

Alessio Ferrari, Gianluca Speranza

Retaining structures above groundwater level support soils that are usually in a state of partial saturation and subject to the actions of atmospheric agents. The current design approach considers the possible extremes of soil conditions - either totally dry or totally saturated - but it neglects matric suction's contribution to soil shear strength. This work aims to describe how unsaturated-soil mechanics of can positively influence the sustainability of retaining structures through a holistic, multidisciplinary, geotechnical, and environmental analysis. The geotechnical analysis allows to estimate the lateral earth pressure of a geostructure in both unsaturated and extreme soil conditions (dry or saturated), which will directly influence the geometrical dimensions of the geostructure. Next, the environmental analysis is performed with the standardized and globally applied Life Cycle Assessment (LCA) tool, in order to quantify the potential environmental impacts of the retaining structure according to both a life cycle and a multi-criteria perspective. First, an LCA model is built for a cantilever retaining wall according to two design approaches: (a) an unsaturated design approach (UDA), i.e. when unsaturated soils' principles are considered in the design procedure, and (b) a conventional design approach (CDA), i.e. if soil is considered dry or saturated. Three different types of retained soil (i.e. fine-grained soil, volcanic ash, and coarse-grained soil) are considered. Then, the associated environmental impacts on climate change, human health, ecosystems and resources are calculated for the two design approaches. Their comparison allows to quantify the potential reductions in environmental damages provided by the adoption of unsaturated-soil mechanics. The presented case study shows a high potential reduction in environmental impacts for retaining walls interacting with fine-grained soils (silt), lower potential environmental benefits with volcanic ash (clayey-silty sand), but no environmental gain for interaction with a coarse-grained soil (sand) compared to a conventional design approach considering extreme soil conditions. (c) 2021 Elsevier Ltd. All rights reserved.

ELSEVIER2022

Life cycle environmental assessment of retaining walls in unsaturated soils

Alessio Ferrari, Gianluca Speranza

ELSEVIER2022