Development of Roughness Prediction Models for Life Cycle Assessment Studies of Recycled Pavement Projects

Author(s):  
Eugene A. Amarh ◽  
Gerardo W. Flintsch ◽  
Joao Santos ◽  
Brian K. Diefenderfer

The few existing life cycle assessment studies considering pavement recycling techniques usually omit the stages of maintenance and rehabilitation (M&R) and use. The reason for this omission is the lack of information about how the pavement’s performance evolves over time and absence of methods to determine the M&R frequency and service life for completed projects. As a result, the deterioration of pavement recycling projects in the long term is not clearly understood. Few projects have available data, the majority of which are on low volume primary and secondary roads. This paper describes an approach to develop a family of roughness models for recycling projects in Colorado using functional data analysis, and individual models for selected projects in Virginia to support ongoing life cycle assessment (LCA) studies. In the case of Colorado, full depth reclamation (FDR) projects will most likely deteriorate following an average group rate of 1.4 in./mi/year, with an initial international roughness index (IRI) between 52 and 70 in./mi. For the individual roughness models developed for Virginia projects, the initial IRI values and the rate of change for the treatments analyzed were found to range between 49 and 107 in./mi and between 0.7 and 5.2 in./mi/year, respectively, depending on the recycling method and type of stabilization treatment. The results of an LCA case study show that, in addition to recycling, Virginia Department of Transportation can achieve statewide emission reduction goals if focus is placed on achieving smoother roads while measures are taken to keep the annual rates of deterioration low.

Robotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 33
Author(s):  
Florian Stuhlenmiller ◽  
Steffi Weyand ◽  
Jens Jungblut ◽  
Liselotte Schebek ◽  
Debora Clever ◽  
...  

Modern industry benefits from the automation capabilities and flexibility of robots. Consequently, the performance depends on the individual task, robot and trajectory, while application periods of several years lead to a significant impact of the use phase on the resource efficiency. In this work, simulation models predicting a robot’s energy consumption are extended by an estimation of the reliability, enabling the consideration of maintenance to enhance the assessment of the application’s life cycle costs. Furthermore, a life cycle assessment yields the greenhouse gas emissions for the individual application. Potential benefits of the combination of motion simulation and cost analysis are highlighted by the application to an exemplary system. For the selected application, the consumed energy has a distinct impact on greenhouse gas emissions, while acquisition costs govern life cycle costs. Low cycle times result in reduced costs per workpiece, however, for short cycle times and higher payloads, the probability of required spare parts distinctly increases for two critical robotic joints. Hence, the analysis of energy consumption and reliability, in combination with maintenance, life cycle costing and life cycle assessment, can provide additional information to improve the resource efficiency.


2019 ◽  
Vol 887 ◽  
pp. 319-326 ◽  
Author(s):  
Benedek Kiss ◽  
Zsuzsa Szalay

In the environmental analysis of buildings, Life Cycle Assessment (LCA) is gaining more and more interest. It is due to the fact, that LCA is very comprehensive in considering many impacts in all life-cycle phases of the examined building. Since buildings have a complicated geometry that is built up with numerous constructions that consist of many materials, and the life-cycle includes many phases, the results of an assessment are likely to be difficult to analyze in detail. In this paper we introduce a visual method to help architects and analysts to quickly understand the results of an environmental assessment. It includes the hierarchic visualization of the performance of the individual elements of the building. Both energy use and environmental impacts can be presented. Also the contribution of the different life-cycle phases in the overall impact is visualized.There are increasing efforts nowadays to find the most efficient way to improve the environmental performance of buildings. This can be supported with a detailed analysis of the results. The method is presented through a case study of a realized energy efficient one-family house.


2021 ◽  
Vol 13 (6) ◽  
pp. 3443
Author(s):  
Jana Gerta Backes ◽  
Julian Suer ◽  
Nils Pauliks ◽  
Sabrina Neugebauer ◽  
Marzia Traverso

The current dependency on steel within modern society causes major environmental pollution, a result of the product’s life cycle phases. Unfortunately, very little data regarding single steel production processes have been found in literature. Therefore, a detailed analysis of impacts categorized in terms of relevance cannot be conducted. In this study, a complete life cycle assessment of steel production in an integrated German steel plant of thyssenkrupp Steel Europe AG, including an assessment of emissions from the blast furnace, the basic oxygen furnace, and casting rolling, is carried out. The functional unit is set to 1 kg hot-rolled coil, and the system boundaries are defined as cradle-to-gate. This study models the individual process steps and the resulting emitters using the software GaBi. Total emissions could be distributed into direct, upstream, and by-product emissions, where the biggest impacts in terms of direct emissions from single processes are from the power plant (48% global warming potential (GWP)), the blast furnace (22% GWP), and the sinter plant (79% photochemical ozone creation potential (POCP)). The summarized upstream processes have the largest share in the impact categories acidification potential (AP; 69%) and abiotic depletion potential fossil (ADPf; 110%). The results, including data verification, furthermore show the future significance of the supply chain in the necessary reduction that could be achieved.


2014 ◽  
Vol 23 (1) ◽  
pp. 103-124 ◽  
Author(s):  
Daniel Kopasker

Existing research has consistently shown that perceptions of the potential economic consequences of Scottish independence are vital to levels of support for constitutional change. This paper attempts to investigate the mechanism by which expectations of the economic consequences of independence are formed. A hypothesised causal micro-level mechanism is tested that relates constitutional preferences to the existing skill investments of the individual. Evidence is presented that larger skill investments are associated with a greater likelihood of perceiving economic threats from independence. Additionally, greater perceived threat results in lower support for independence. The impact of uncertainty on both positive and negative economic expectations is also examined. While uncertainty has little effect on negative expectations, it significantly reduces the likelihood of those with positive expectations supporting independence. Overall, it appears that a general economy-wide threat is most significant, and it is conjectured that this stems a lack of information on macroeconomic governance credentials.


2020 ◽  
Vol 5 (4) ◽  
pp. 223-229
Author(s):  
Yuliia Slyva ◽  
◽  
Oleksiy Verenikin ◽  

The research on the development of an innovative formula of a synthetic detergent with improved environmental properties, which meet the environmental standard of SOU OEM 08.002.12.065:2016 "Detergents and cleaning products. Environmental criteria for life cycle assessment" is carried out. The accumulated theoretical and practical experience is generalized, the general scheme of designing and development of new goods taking into account features of detergents with the improved ecological characteristics is created.


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