Regionalized environmental impacts of construction machinery

Abstract

Purpose This study aims to establish a regionalized environmental impact assessment of construction machinery equipped with diesel engines certified by the European emission standard Stage V, and operated in cold climatic zones in Europe. Method The study quantifies potential environmental impacts associated with construction machinery over the entire lifecycle, from extraction of materials to the end-of-life. For the operation phase, a meso-level emission accounting method is applied to quantify tailpipe emissions for certain subcategories of construction machinery. This is achieved by determining the operational efficiency of each machine in terms of effective hours. The quantified emission data are then adjusted based on engine deterioration models to estimate the rate of increase in emissions throughout the lifetime of each machine. Finally, the CML impact assessment method is applied to inventory data to quantify potential environmental impacts. Results The study shows that tailpipe emissions, which largely depend on an engine's fuel consumption, had the largest contribution to environmental impacts in most impact categories. At the same time, there was a positive correlation between the operation weight and the impacts of the machinery. Also, machinery with similar operation weight had relatively similar impact patterns due to similar driving factors and dependencies. In addition, network, sensitivity, and uncertainty analyses were performed to quantify the source of impacts and validate the robustness of the study. Results of the sensitivity analysis showed that the responsiveness of the studied systems is very sensitive to changes in the amount of fuel consumption. In addition, the uncertainty results showed that the domain of uncertainty increased as the operation weight subcategory of machinery increased. Conclusion This study extends previous work on the life cycle assessment (LCA) of construction machinery, and the methodology developed provides a basis for future extension and improvement in this field. The use of effective hours as the unit of operational efficiency helps to resolve uncertainties linked to lifetime and annual operation hours. Also, the obtained results can be of use for decision support and for assessing the impacts of transition from fossil fuels to alternative fuel types.

D Numbers – Fucom – Fuzzy Rafsi Model for Selecting the Group of Construction Machines for Enabling Mobility

“…Solving resource savings is one of the defining directions of industry and modern economy [2,3]. One of the cost reduction approaches in the construction sector is presented through: assessment of the performance of different types and subcategories of construction machines in different conditions [4][5][6], consideration of critical machine performance (engine speed, engine type, operating hours, torque or engine power, weight of machines, type of fuel, service life of equipment) [7][8][9][10][11], the definition of the maximum allowed idling time, the definition of critical machine, change of type of fuel and mixture, use of machines equipped with newer technology and transition to electrical circuit systems [10,[12][13][14][15].…”

“…In addition to the above mentioned, there are other, so-called external parameters affecting the consumption of resources and are related to the performance of construction machinery, such as climatic and soil conditions, driver/operator experience, terrain slope, soil type, density, and volume of sediment being worked on, etc. [12].…”

Carbon emissions management in construction operations: a systematic review

“…Additionally, the LCA studies conducted during this time frame contain sensitivity analyses to examine the effects of parameter uncertainty on the comparison of construction projects (Nadoushani et al. , 2018; Ebrahimi et al. , 2020; Zhang et al.…”

Environmental Impact of Remanufacturing Mining Machinery

“…The GWP during the service life of the machine accounted for ~80% of the GWP throughout the lifecycle, whereas the GWP in the maintenance process (remanufactured parts are not used) was estimated to be ~6% [19]. Using an LCA approach, Ebrahimi et al [20] quantified the environmental impact of the engine and other components of a construction machine, which was compliant with European emission standards Stage V, at different stages of the lifecycle, from manufacturing to end-of-life disposal. They deduced that a cleaner alternative method was effective for treating end-of-life tires, owing to the tires' very high freshwater aquatic ecotoxicity [20].…”

“…Using an LCA approach, Ebrahimi et al [20] quantified the environmental impact of the engine and other components of a construction machine, which was compliant with European emission standards Stage V, at different stages of the lifecycle, from manufacturing to end-of-life disposal. They deduced that a cleaner alternative method was effective for treating end-of-life tires, owing to the tires' very high freshwater aquatic ecotoxicity [20]. The abovementioned studies used the values estimated from the ecoinvent database, because foreground data, such as the electric power used in manufacturing, were not available.…”