Through-Life Management of Built Facilities: Towards a Framework for Analysis

Although built facilities are required to cater to changing requirements over time, effective through life management is absent as an in-process activity from most large scale procurements. Through a review of key literature, several approaches which address aspects relevant to through-life management are discussed, and an attempt is made to create a unified view framework of understanding of what constitutes through-life management. Furthermore, an initial diagnostic style checklist is provided as a way of identifying the absence of through-life managemen

Advancing automation and robotics technology for the Space Station Freedom and for the US economy

The progress made by levels 1, 2, and 3 of the Office of Space Station in developing and applying advanced automation and robotics technology is described. Emphasis is placed upon the Space Station Freedom Program responses to specific recommendations made in the Advanced Technology Advisory Committee (ATAC) progress report 10, the flight telerobotic servicer, and the Advanced Development Program. Assessments are presented for these and other areas as they apply to the advancement of automation and robotics technology for the Space Station Freedom

Advanced General Aviation Turbine Engine (GATE) concepts

Concepts are discussed that project turbine engine cost savings through use of geometrically constrained components designed for low rotational speeds and low stress to permit manufacturing economies. Aerodynamic development of geometrically constrained components is recommended to maximize component efficiency. Conceptual engines, airplane applications, airplane performance, engine cost, and engine-related life cycle costs are presented. The powerplants proposed offer encouragement with respect to fuel efficiency and life cycle costs, and make possible remarkable airplane performance gains

Greenhouse Gas Reduction Opportunities for Local Governments: A Quantification and Prioritization Framework

Local governments have steadily increased their initiative to address global climate change, and many present their proposed strategies through climate action plans (CAPs). This study conducts a literature review on current local approaches to greenhouse gas (GHG) reduction strategies by assessing CAPs in California and presents common strategies in the transportation sector along with useful tools. One identified limitation of many CAPs is the omission of quantitative economic cost and emissions data for decision-making on the basis of cost-effectiveness. Therefore, this study proposes a framework for comparing strategies based on their life cycle emissions mitigation potential and costs. The results data can be presented in a marginal abatement cost curve (MACC) to allow for side-by-side comparison of considered strategies. Researchers partnered with Yolo and Unincorporated Los Angeles Counties to analyze 7 strategies in the transportation and energy sectors (five and two, respectively). A MACC was subsequently developed for each county. Applying the life cycle approach revealed strategies that had net cost savings over their life cycle, indicating there are opportunities for reducing emissions and costs. The MACC also revealed that some emissions reduction strategies in fact increased emissions on a life cycle basis. Applying the MACC framework to two case study jurisdictions illustrated both the feasibility and challenges of including quantitative analysis in their decision-making process. An additional barrier to using the MACC framework in the context of CAPs, is the mismatch between a life cycle and annual accounting basis for GHG emissions. Future work could explore more efficient data collection, alternative scopes of emissions for reporting, and environmental justice concerns.View the NCST Project Webpag

Stainless Steel Corrugated Web Girders for Composite Road Bridges: Concept Evaluation and Flange Buckling Resistance

Achieving a sustainable bridge design requires careful consideration of economic viability and environmental impact over the entire lifespan of the structure. While stainless steel is recognized for its excellent life cycle performance, its high cost prevents it from being used to a larger extent in bridges. In this thesis work, a new solution is investigated to mitigate this issue. The new solution comprises the use of corrugated webs in stainless steel girders which is expected to result in reduced material consumption and cost. The work in this thesis focuses on two problem areas in this field. First, a study is performed to examine the competitiveness of the new concept in relation to conventional designs of steel-concrete composite road bridges. The second part of the work focuses on the problem of flange buckling in girders with corrugated webs. Previous research has shown that the design models developed\ua0for flange buckling resistance, including the one in EN 1993-1-5, frequently result in unsafe design. Furthermore, these models were developed for carbon steel and have not been updated for stainless steel. To explore the economic and environmental benefits of the new concept, two studies have been conducted. Firstly, three design solutions are examined on a case study bridge with three continuous spans. These design solutions include carbon steel flat web, stainless steel flat web, and stainless steel corrugated web girder bridges. A genetic algorithm is used to optimize each design solution in terms of weight. The three optimal solutions are then assessed in terms of investment costs, life cycle costs (LCC), and environmental life cycle impact. Secondly, two of the considered design solutions, namely carbon steel flat web and stainless-steel corrugated web girders, are employed to conduct multiple parametric studies using a simply supported reference bridge. For both design solutions, the effects of optimization targets on weight, investment cost, life cycle cost, and environmental life cycle impact are initially investigated. Following that, the focus is put on the life cycle cost (LCC) as an optimization target, and the impact of various design input parameters is investigated. These parameters include span length, girder depth, average daily traffic (ADT) with the associated number of heavy vehicles per slow lane (Nobs), and time intervals and expenses for maintenance activities. Furthermore, a sensitivity analysis is conducted to study the influence of the inflation rate and discount rate. The results indicate that the new concept offers considerable potential saving in weight, life cycle costs, and life cycle impacts for both simply supported and continuous bridges. The saving is more apparent with deeper girders, higher ADT, and more intense maintenance activities. Saving is also larger when inflation is high and discount rate is low.After studying the potential of corrugated web girders to reduce costs and environmental impacts in the case of employing stainless steel, a study of the flange buckling behaviour in duplex stainless-steel girders is conducted in this work. A parametric finite element model is developed and validated with tests conducted on beams made of carbon steel. The material is then changed to EN1.4162, and linear buckling analysis (LBA) and geometrically and materially nonlinear analysis with imperfections (GMNIA) are carried out on 410 girders with typical bridge girder dimensions. The results are compared to previously developed models for carbon steel, and a new buckling curve and flange local buckling design procedure for duplex stainless-steel girders with corrugated webs are proposed. The study shows that the new proposed design model generates more accurate estimates of flange buckling resistance than previous proposed models

High-performance materials in infrastructure: a review of applied life cycle costing and its drivers – the case of fiber-reinforced composites

IIn recent years, an investment bottleneck for public infrastructure has accumulated in many industrial countries. Life cycle costing (LCC) is an appropriate management instrument for long-term and sustainable investment. This article addresses the evaluation of high-performance materials (HPM) using LCC to reduce that investment bottleneck. Our research questions are, first, whether and how LCC can be applied to HPM, second, which drivers are primarily influencing the results of a LCC analysis for HPM, and finally, whether HPM are suitable for infrastructure investments, according to economic, social and environmental criteria. We use a comprehensive literature review to analyze existing case studies that apply LCC to HPM. Our review shows that LCC is applied to HPM for structural applications with different levels of detail and quality. The initial results indicate that total life cycle costs for HPM are on average 10% higher. We urge the optimization of the cost structure of HPM to achieve the same level of life cycle costs as conventional construction materials. Moreover, we argue for a more holistic approach that does not ignore sustainability criteria throughout the life cycle of HPM based on the identified drivers of life cycle costs: external costs, an extended life cycle, the discount rate and the expected service life. Indeed, a screened subsample of eight cases is very competitive, with average total life cycle costs for HPM that are 8.4% lower. We share the belief in a more eco-centric approach and, therefore, demand further research into a societal type of LCC that improves the mechanical properties while not ignoring sustainability criteria for new product systems such as HPM

Social Life Cycle Assessment for Additive Manufacturing: A Review

The aim of this dissertation is to assist in the development of the project FIBR3D – Hybrid Processes based on Additive Manufacture of Thermoplastic Matrix Composites Reinforced with Fibers, by providing a base insight on the Social Life Cycle Assessment methodology (SLCA) and other related methodologies. The main objective of this dissertation is to present a literature review to identify the existing life cycle based methodologies, which will give a base knowledge on how they work and how they can be implemented within the project FIBR3D. This study will help in the development of a life cycle based parametric model that will be used to assess the Additive Manufacturing technology that is being developed within the project. The main objective of this work is to study the Social Life Cycle Assessment methodology (SLCA), although it is considered that first it is needed to understand how the environmental Life Cycle Assessment (LCA) and the Life Cycle Costing (LCC) methodologies work, because they retain some similarities with each other and can be connected to create the Life Cycle Sustainability Assessment methodology (LCSA). After the study of the other two methodologies, the Social Life Cycle Assessment is analyzed with more detail. These methodologies were studied by analyzing information from papers, book chapters and standards. The keywords that were used in the search of the selected documents were, for example, “Life Cycle Assessment”, “Life Cycle Costing” and “Social Life Cycle Assessment”. After analyzing the selected documents, the information was summarized in tables so it is possible to conclude what can help in the development of the project and what can still be studied in more depth. In this dissertation 17 papers about LCA and LCC and 13 papers about SLCA are analyzed. In addition to the papers, some standards were also studied, because they are considered essential in the study of these methodologies. From all the analyzed papers, only two tried to link the SLCA methodology with the additive manufacturing technology (AM), which was unexpected, but plausible because the AM is a technology still under development. With the analysis of the papers it is possible to perceive that there is a great need to develop studies that apply these methodologies to assess the AM technology and products/processes in the phase of development. Apparently, despite the scarcity of studies, it is already clear that the AM technology is considered to have an immense potential to revolutionize industries and to change some standards at the social and society level