Punching above its weight: life cycle energy accounting and environmental assessment of vanadium microalloying in reinforcement bar steel

Aggregate consumption rates have now exceeded natural renewal rates, signaling shortages both locally and globally. Even more concerning is that the worldwide markets for construction aggregates are projected to grow at an annual rate of 5.2% in the near future. This increase is attributed to rapid population growth coupled with the economic development worldwide. In terms of material availability, one of the most vulnerable regions is the Asia-Pacific region specifically, Singapore, where there is higher demand but limited availability of natural sand and gravel for use as aggregates in concrete construction projects. This paper focuses mainly on the environmental impacts of fine aggregate alternatives used in high-strength concrete applications in Singapore, which is one of the major global importers of natural sand following China. Singapore has been experiencing political and environmental challenges linked to the shortage of natural sand use as aggregates, even while the demand is increasing in the construction sector. Copper slag, a readily available waste material from shipyards in Singapore, is a possible replacement material for a portion of the natural sand in concrete mixtures, thus sustaining the projected growth in the region. A life-cycle assessment approach is applied to investigate the environmental impacts of copper slag and its alternative use as natural sand in high-strength concrete applications in Singapore. The system boundary consists of the major production processes of concrete constituents (including Portland cement and fine and coarse aggregates, with CS considered as fine aggregate) from a cradle-to-gate perspective, consisting of relevant life-cycle phases of raw materials extraction, transportation, and production processes at the relevant facility where the production occurs. Output from the assessment is provided in terms of embodied energy use and air emissions of concrete mixes with varying percentages of copper slag as fine aggregate. Results show that environmental impacts of aggregates decrease with the increasing substitution rate of natural sand with copper slag when calculated on the basis per unit volume of the concrete mix. For example, 40% and 100% sand replacements with copper slag result in a reduction of 8% and 40% in embodied energy, 12% and 30% in global warming potential, 8% and 41% in acidification, and 7% and 35% in particulate matter formation, respectively. Normalized impacts (i.e., normalized with respect to compressive strength) are observed to remain at almost similar levels for concrete mixes with up to 40% natural sand having been replaced with copper slag. Therefore, it is recommended that replacement of fine aggregates by 40–50% of copper slag (by weight) will produce concrete mixtures with comparable environmental impacts while maintaining feasible durability and strength properties.

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Environmental Assessment of Buildings – A Suggestion

Slovak Journal of Civil Engineering ◽

10.2478/sjce-2020-0003 ◽

2020 ◽

Vol 28 (1) ◽

pp. 20-24

Author(s):

Martin Jamnický ◽

Roman Rabenseifer

Keyword(s):

Life Cycle ◽

Service Life ◽

Environmental Assessment ◽

Energy Demand ◽

Input Data ◽

Building Envelope ◽

Embodied Energy ◽

Actual Case ◽

Detached House

AbstractThis article proposes to contribute to the discussion on environmental product declarations for buildings. Using a simple life-cycle analysis of a low-energy detached house and CO2-equivalent emissions as a comparative unit, the case study presented illustrates the problems with the initial input data related to embodied energy and a definition of the criteria for an assessment of the environmental quality of buildings. The actual case study compares the expected energy demand of a detached house in the course of its service life and the energy input (embodied energy) necessary for its assembly and for the manufacture of the individual building products. The operation of the building during its service life is described using a computer-aided building performance simulation. The input data related to the embodied energy are based on information from classical works on life cycle analyses. In addition, the article discusses the limits of building envelope improvements in terms of the thickness of thermal insulation and also stresses the increasing significance of embodied energy in the environmental assessment of buildings.

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The importance of embodied energy in carbon footprint assessment

Structural Survey ◽

10.1108/ss-01-2013-0012 ◽

2014 ◽

Vol 32 (1) ◽

pp. 49-60 ◽

Cited By ~ 31

Author(s):

Zaid Alwan ◽

Paul Jones

Keyword(s):

Life Cycle ◽

Carbon Footprint ◽

Embodied Energy ◽

Total Carbon ◽

Design Team ◽

Content Type ◽

Operational Energy ◽

The Impact ◽

Whole Life Cycle

Purpose – The construction industry has focused on operational and embodied energy of buildings as a way of becoming more sustainable, however, with more emphasis on the former. The purpose of this paper is to highlight the impact that embodied energy of construction materials can have on the decision making when designing buildings, and ultimately on the environment. This is an important aspect that has often been overlooked when calculating a building's carbon footprint; and its inclusion this approach presents a more holistic life cycle assessment. Design/methodology/approach – A building project was chosen that is currently being designed; the design team for the project have been tasked by the client to make the facility exemplary in terms of its sustainability. This building has a limited construction palette; therefore the embodied energy component can be accurately calculated. The authors of this paper are also part of the design team for the building so they have full access to Building Information Modelling (BIM) models and production information. An inventory of materials was obtained for the building and embodied energy coefficients applied to assess the key building components. The total operational energy was identified using benchmarking to produce a carbon footprint for the facility. Findings – The results indicate that while operational energy is more significant over the long term, the embodied energy of key materials should not be ignored, and is likely to be a bigger proportion of the total carbon in a low carbon building. The components with high embodied energy have also been identified. The design team have responded to this by altering the design to significantly reduce the embodied energy within these key components – and thus make the building far more sustainable in this regard. Research limitations/implications – It may be is a challenge to create components inventories for whole buildings or for refurbishments. However, a potential future approach for is application may be to use a BIM model to simplify this process by imbedding embodied energy inventories within the software, as part of the BIM menus. Originality/value – This case study identifies the importance of considering carbon use during the whole-life cycle of buildings, as well as highlighting the use of carbon offsetting. The paper presents an original approach to the research by using a “live” building as a case study with a focus on the embodied energy of each component of the scheme. The operational energy is also being calculated, the combined data are currently informing the design approach for the building. As part of the analysis, the building was modelled in BIM software.

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Environmental Assessment of Buildings Constructed by Modern Methods of Construction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.861.601 ◽

2016 ◽

Vol 861 ◽

pp. 601-608 ◽

Cited By ~ 1

Author(s):

Daniela Mackova ◽

Marcela Spisakova ◽

Mária Kozlovská ◽

Jozef Svajlenka

Keyword(s):

Life Cycle ◽

Environmental Assessment ◽

Product Life Cycle ◽

Building Materials ◽

Embodied Energy ◽

Negative Effects ◽

Modern Methods ◽

Acidification Potential ◽

Cradle To Gate

Currently, we are witnessing the significant impact of industrial activity on the environment. A recent study shows that construction is the third largest industry sector in terms of environmental pollution. One option to reduce these negative effects is environmental assessment of buildings, as well as the used building materials. One of the most comprehensive environmental assessment methods is LCA (Life Cycle Assessment), which includes the assessment of impacts within mode ”Cradle-to-gate” which is focused on assessment of a partial product life cycle from resource extraction (cradle) to the factory gate (i.e., before it is transported to the consumer). The aim of this paper is a comparison of the environmental impact of selected material variants applied within modern methods of construction. The comparison will be processed through the results of the case study containing three material variants of family houses construction in term of three selected parameters - embodied energy, global warming potential and acidification potential.

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Punching Above its Weight: Life Cycle Energy Accounting and Environmental Assessment of Vanadium Microalloying in Reinforcement Bar Steel

10.26434/chemrxiv.13090265.v1 ◽

2020 ◽

Author(s):

Pranav Pradeep Kumar ◽

David A. Santos ◽

Erick J. Braham ◽

Diane G. Sellers ◽

Sarbajit Banerjee ◽

...

Keyword(s):

Life Cycle ◽

Carbon Footprint ◽

Chemical Elements ◽

Carbon Steels ◽

Embodied Energy ◽

Global Perspective ◽

Microalloyed Steels ◽

Lower Grade ◽

Low Alloy Steels ◽

The Impact

The manuscript presents a detailed analysis of embodied energy and carbon footprint reduction enabled by microalloying of steel, thereby providing a rich global perspective of the (outsized) role of chemical elements added in trace concentrations on the overall footprint of the construction industry. As such, the manuscript addresses an important and timely topic at the intersection of materials criticality, structural performance, life cycle assessment, and policy interventions. The United Nations estimates that the worldwide energy consumption of buildings accounts for 30—40% of global energy production, underlining the importance of the judicious selection of construction materials. Much effort has focused on the use of high-strength low-alloy steels in reinforcement bars whose economy of materials use is predicated upon improved yield strengths in comparison to low-carbon steels. While microalloying is known to allow for reduced steel consumption, a sustainability analysis in terms of embodied energy and CO 2 has not thus far been performed. Here we calculate the impact of supplanting lower grade reinforcement bars with higher strength vanadium microalloyed steels on embodied energy and carbon footprint. We find that the increased strength of vanadium microalloyed steel translates into substantial material savings over mild steel thus reducing the total global fossil carbon footprint by as much as 0.385%. A more granular analysis pegs savings for China and the European Union at 1.01 and 0.19%, respectively, of their respective emissions.

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Reducing carbon footprint of facilities using a facility management approach

Facilities ◽

10.1108/f-11-2014-0091 ◽

2016 ◽

Vol 34 (3/4) ◽

pp. 247-259 ◽

Cited By ~ 11

Author(s):

Manish K. Dixit ◽

Charles H. Culp ◽

Jose L. Fernandez-Solis ◽

Sarel Lavy

Keyword(s):

Life Cycle ◽

Case Studies ◽

Carbon Footprint ◽

Management Practices ◽

Facility Management ◽

Embodied Energy ◽

Management Approach ◽

Facilities Management ◽

Life Cycle Approach ◽

Content Type

Purpose The purpose of this paper is to emphasize the importance of a life cycle approach in facilities management practices to reduce the carbon footprint of built facilities. A model to holistic life cycle energy and carbon reduction is also proposed. Design/methodology/approach A literature-based discovery approach was applied to collect, analyze and synthesize the results of published case studies from around the globe. The energy use results of 95 published case studies were analyzed to derive conclusions. Findings A comparison of energy-efficient and conventional facilities revealed that decreasing operating energy may increase the embodied energy components. Additionally, the analysis of 95 commercial buildings indicated that nearly 10 per cent of the total US carbon emissions was influenced by facilities management practices. Research limitations/implications The results were derived from case studies that belonged to various locations across the globe and included facilities constructed with a variety of materials. Practical implications The proposed approach to holistic carbon footprint reduction can guide facility management research and practice to make meaningful contributions to the efforts for creating a sustainable built environment. Originality/value This paper quantifies the extent to which a facilities management professional can contribute to the global efforts of reducing carbon emission.

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Environmental impact assessment of vernacular thatch building tradition in Mexico: Case studies of three palm species and related technology along the Trans-Mexican Volcanic Belt

10.26686/wgtn.17012414.v1 ◽

2021 ◽

Author(s):

◽

Jaime Jesús Rios Calleja

Keyword(s):

Life Cycle ◽

Environmental Impact ◽

Case Studies ◽

Environmental Assessment ◽

Volcanic Belt ◽

Embodied Energy ◽

Ecological Footprints ◽

Mexican Volcanic Belt ◽

Palm Species ◽

Vernacular Buildings

This project involves research into vernacular buildings, in particular traditional and contemporary coastal palm thatch buildings in the middle-west coast deciduous forest environments in Mexico. The fieldwork-based grounded theory research investigates the natural materials and techniques involved in constructing thatched vernacular buildings using three different palm species (Attalea guacuyule, Brahea dulcis and Sabal rosei) in different climatic contexts along the Trans Mexican Volcanic Belt (TMVB). The aim is to achieve a holistic approach to the environmental assessment of these building types through a life-cycle assessment. The present research emerges from the premise that vernacular buildings are generally taken for granted as sustainable, and yet they are under-investigated meaning this assumption may not be correct. In general the performance of vernacular buildings in terms of sustainability and in relation to their embodied energy is under reported, particularly in terms of vernacular case studies in Mexico. However the deterioration of the environments where such buildings are located through anthropogenic causes is of world-wide importance, therefore it is a priority for this research to study the relationship of the vernacular traditions with their immediate environment. The first section of the thesis analyses theoretical frameworks for sustainability and vernacular architecture. Both terms are widely used and carry many different meanings, so it is important to establish the definitions used in this research to better set the boundaries of the study as a basis for seeking the best methods for assessing the environmental impact of the selected vernacular thatch building technologies. The second section undertakes qualitative and quantitative fieldwork on traditional practices of palm thatch buildings in selected regions of Mexico and related case studies, six in total. The fieldwork was combined with investigation into ethnographical, ethnobotanical and historical records and data for the three palms used for thatching and their related materials and technologies in order to derive data concerning yield factors, lifespan of the building materials, carrying capacities, embodied energy of transport and embodied energy of materials. The third section applies the collected information for a life-cycle environmental assessment (LCA) of two typical buildings for each of the three different palm species and the diverse techniques involved. The assessment is carried out based on various assumptions that are commonly used in LCA to give a carbon account and an ecological footprint for each building component both after construction and for a 50 year building life. However, during the research particular variables in the analysis were revealed, such as operating energy, recycling of building elements, durability of materials and transport practices, which can vary widely from case to case, therefore the limits and scope of the assessment excluded such data for a better comparative scenario of the building process itself. This suggests that a different way of life-cycle accounting may be needed when assessing vernacular structures. The results show the environmental impact of these techniques in terms of carbon and ecological footprints, and reveal that the rural vernacular case studies had lower environmental impacts than the suburban and urban vernacular case studies as measured by their carbon content, energy expressed in Giga Joules (GJ) and their ecological footprints.

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Should the Same Products Consumed in Different Retail Channels Have an Identical Carbon Footprint? An Environmental Assessment of Consumer Preference of Retail Channels and Mode of Transport

Sustainability ◽

10.3390/su13020615 ◽

2021 ◽

Vol 13 (2) ◽

pp. 615

Author(s):

Jenhung Wang ◽

Pei-Chun Lin

Keyword(s):

Life Cycle ◽

Environmental Impact ◽

Carbon Footprint ◽

Environmental Assessment ◽

Distribution Systems ◽

Consumer Preference ◽

Transportation Mode ◽

Retail Channels ◽

Mode Of Transport ◽

The Impact

This study involved an environmental assessment of retail channels using the simplified life-cycle assessment (LCA) method to quantify the environmental impact of packaged beverages consumed in 7-Eleven convenience stores (c-stores) and Carrefour hypermarkets, with the aim of offering shoppers more environmentally friendly chain stores. The life-cycle impact assessment (LCIA) of packaged drinks at the point of sale (POS) shows the environmental impact of (1) consumer transportation mode and (2) truck distribution. A comparative analysis was conducted on the consumption of 1800 cartons of packaged beverages in c-stores compared to hypermarket channels replenished by individual distribution systems. The paired t-test was used to assess the impact of the consumption of 1800 boxes of 24 packs of 10-ounce drinks. The significance level of the beverages consumed in Carrefour and 7-Eleven c-stores differed by 0.1. The logistics-focused LCA explained the environmental and business rationale for replenishment and sustainable customer transportation. We conclude that, due to consumer preference for retail channels and mode of transport, the carbon footprint for the same products consumed in different channels should not be identical. The research demonstrated a tool to convey more environmental profiles of transportation mode selection to consumers and contribute to building sustainable communities.

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Effect of fly ash on the service life, carbon footprint and embodied energy of high strength concrete in the marine environment

Energy and Buildings ◽

10.1016/j.enbuild.2017.12.011 ◽

2018 ◽

Vol 158 ◽

pp. 1694-1702 ◽

Cited By ~ 24

Author(s):

Pradip Nath ◽

Prabir K. Sarker ◽

Wahidul K. Biswas

Keyword(s):

Fly Ash ◽

Service Life ◽

Marine Environment ◽

Carbon Footprint ◽

High Strength Concrete ◽

High Strength ◽

Embodied Energy ◽

Strength Concrete

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Punching Above its Weight: Life Cycle Energy Accounting and Environmental Assessment of Vanadium Microalloying in Reinforcement Bar Steel

10.26434/chemrxiv.13090265 ◽

2020 ◽

Author(s):

Pranav Pradeep Kumar ◽

David A. Santos ◽

Erick J. Braham ◽

Diane G. Sellers ◽

Sarbajit Banerjee ◽

...

Keyword(s):

Life Cycle ◽

Carbon Footprint ◽

Chemical Elements ◽

Carbon Steels ◽

Embodied Energy ◽

Global Perspective ◽

Microalloyed Steels ◽

Lower Grade ◽

Low Alloy Steels ◽

The Impact

The manuscript presents a detailed analysis of embodied energy and carbon footprint reduction enabled by microalloying of steel, thereby providing a rich global perspective of the (outsized) role of chemical elements added in trace concentrations on the overall footprint of the construction industry. As such, the manuscript addresses an important and timely topic at the intersection of materials criticality, structural performance, life cycle assessment, and policy interventions. The United Nations estimates that the worldwide energy consumption of buildings accounts for 30—40% of global energy production, underlining the importance of the judicious selection of construction materials. Much effort has focused on the use of high-strength low-alloy steels in reinforcement bars whose economy of materials use is predicated upon improved yield strengths in comparison to low-carbon steels. While microalloying is known to allow for reduced steel consumption, a sustainability analysis in terms of embodied energy and CO 2 has not thus far been performed. Here we calculate the impact of supplanting lower grade reinforcement bars with higher strength vanadium microalloyed steels on embodied energy and carbon footprint. We find that the increased strength of vanadium microalloyed steel translates into substantial material savings over mild steel thus reducing the total global fossil carbon footprint by as much as 0.385%. A more granular analysis pegs savings for China and the European Union at 1.01 and 0.19%, respectively, of their respective emissions.

Download Full-text