Evaluation of Carbon Dioxide Emissions amongst Alternative Slab Systems during the Construction Phase in a Building Project

Global warming is now considered to be one of the greatest challenges worldwide. International environmental agreements have been developed in response to climate change since the 1970s. The construction industry is considered one of the main contributors to global warming. In order to mitigate global warming effects, the construction industry has been exploring various approaches to mitigate the impacts of carbon dioxide emissions over the entire life cycle of buildings. The application of different structural systems is considered a means of reducing the carbon dioxide emissions from building construction. The purpose of this research is to assess the environmental performance of three different slab systems during the construction phase. In this study, a process-based life cycle assessment (LCA) method was applied in order to evaluate the level of performance of the three slab systems. The results showed total CO2 emissions of 3,275,712, 3,157,260, and 2,943,695 kg CO2 eq. for the ordinary reinforced concrete slab, flat plate slab, and voided slab systems, respectively. The manufacturing of building materials is by far the main contributor to CO2 emissions, which indicate 3,230,945, 3,117,203, and 2,905,564 kg CO2 eq., respectively. Comparing the building materials in the three slab systems, reinforcing bars and forms were significant building materials to reduce the CO2 emissions in the flat plate slab and voided slab systems. In this study, reinforcing bars were the main contributor to lowering the carbon dioxide emissions in the flat plate slab and voided slab systems. The results of this study show that amongst all the three different slab systems, the voided slab system shows the greatest reduction potential. Moreover, replacing the ordinary reinforced concrete slab system by alternative methods would make it possible to reduce the carbon dioxide emissions in building projects.

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Comparison of Carbon Dioxide Emissions of the Ordinary Reinforced Concrete Slab and the Voided Slab System During the Construction Phase: A Case Study of a Residential Building in South Korea

Sustainability ◽

10.3390/su11133571 ◽

2019 ◽

Vol 11 (13) ◽

pp. 3571 ◽

Cited By ~ 1

Author(s):

Inkwan Paik ◽

Seunguk Na

Keyword(s):

Carbon Dioxide ◽

Life Cycle ◽

Reinforced Concrete ◽

South Korea ◽

Construction Industry ◽

Carbon Dioxide Emissions ◽

Building Materials ◽

Concrete Slab ◽

Reinforced Concrete Slab

The construction industry not only consumes a lot of energy but also emits large volumes of carbon dioxide. Most countries have established target reduction values of the carbon dioxide emissions to alleviate environmental burdens and promote sustainable development. The reduction in carbon dioxide emissions in the construction industry has been taking place in various ways as buildings produce large quantities of the carbon dioxide over their construction life cycle. The aim of this study is to assess and compare the carbon dioxide emissions of an ordinary reinforced concrete slab and the voided slab system applied to a case study involving a commercial-residential complex building in South Korea. Process-based life-cycle assessment (LCA) is adopted to compute the carbon dioxide emissions during the construction phase, which includes all processes from material production to the end of construction. The results indicate that the total CO2 emissions are 257,230 and 218,800 kg CO2 for the ordinary reinforced concrete slab and the voided slab system, respectively. The highest contributor to CO2 reduction is the embodied carbon dioxide emissions of the building materials, which accounts for 34,966 kg CO2. The second highest contributor is the transportation of the building materials, accounting for 3417 kg CO2.

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“Cement-Free Product” for Settlement of Ceramic Tiles: An Approach for Greener Construction

Materials Science Forum ◽

10.4028/www.scientific.net/msf.805.403 ◽

2014 ◽

Vol 805 ◽

pp. 403-408

Author(s):

Otávio Luiz do Nascimento ◽

Alexandra Ancelmo Piscitelli Mansur ◽

Herman Sander Mansur

Keyword(s):

Carbon Dioxide ◽

Construction Industry ◽

Free Product ◽

Ceramic Tile ◽

Carbon Dioxide Emissions ◽

Building Materials ◽

Global Climate ◽

Public Awareness ◽

Ceramic Tiles ◽

The Impact

Increased public awareness of the threats posed by global warming has led to greater concern over the impact of anthropogenic carbon emissions on the global climate associated with the level of carbon dioxide (CO2) in the atmosphere. Hence, without radical market, technological, and cultural changes, the CO2 concentrations are expected to rise to unbearable levels within just few decades ahead. The production of cement is estimated to be responsible for approximately 5% of the global carbon dioxide emissions. Consequently, aiming for creating a more sustainable world, engineers and scientists must develop and put into use greener building materials that may revolutionize the entire construction industry. This study presents an innovative product for settlement of ceramic tiles as a potential alternative for replacing the conventional cement based mortar in some specific building applications. Essentially, the novel system is based on a double face polymer-adhesive sheet (“cement-free product”). Thus, the main goal was to evaluate the performance and estimate the durability of the developed system. Pull-off tests were conducted in order to compare this new system to the traditional one, with polymer modified mortar, under different procedures and conditions of cure. In addition, both systems were modeled using Finite Element Method (FEM) to obtain the stresses at the interface between ceramic-tile and adhesive. Based on the results, the recommended limits of bond strength for the innovative “cement-free product” of ceramic tile installation could be lower than those specifications used for the equivalent mortar systems. Therefore, these results give some preliminary evidence that by using the new “cement-free” product for ceramic-tile installation may lead to some increase in the productivity and, more important, in the sustainability of a relevant sector of the construction industry.

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Assessment of CO2 Emissions by Replacing an Ordinary Reinforced Concrete Slab with the Void Slab System in a High-Rise Commercial Residential Complex Building in South Korea

Sustainability ◽

10.3390/su11010082 ◽

2018 ◽

Vol 11 (1) ◽

pp. 82 ◽

Cited By ~ 1

Author(s):

Inkwan Paik ◽

Seunguk Na ◽

Seongho Yoon

Keyword(s):

Reinforced Concrete ◽

Co2 Emissions ◽

Carbon Dioxide Emissions ◽

Raw Materials ◽

Concrete Slab ◽

Lower Amount ◽

Reinforced Concrete Slab ◽

High Rise ◽

Complex Building ◽

Operation Phase

The purpose of this study is to verify the environmental performance of the novel Void Deck Slab (VDS) system developed by the authors. The proposed VDS is a void slab system with enhanced design features that improve the constructability of the system through the elimination of additional works required to connect the void formers with the anchoring devices. The Life Cycle Assessment (LCA) technique was adopted to assess the carbon dioxide emissions of the void slab system with reference to the ordinary reinforced concrete slab. The system boundary of this study ranged from raw materials to pre-operation phase, in accordance with ISO 14044. The total CO2 emissions of the ordinary reinforced concrete slab and the void slab system were 204,433.06 and 151,754.75 kg CO2-eq, respectively, which equated to about 34% less emissions for the void slab system. In the case of the ordinary reinforced concrete slab, moulds accounted for approximately 62% of CO2 emission, followed by concrete (~34%). The main source of CO2 emissions for the void slab system was concrete that accounted for ~50%, followed by moulds and deck plates that accounted for roughly 27% and 19%, respectively. In the case of the void slab system, void formers would enable a lower amount of concrete, as well as the self-weight of the slab. Besides, although the void formers filled a significant volume of the slab, the contribution to CO2 emissions was less than 1%.

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Characteristics of lime-hemp composite and its use in construction industry

Budownictwo i Architektura ◽

10.35784/bud-arch.1639 ◽

2015 ◽

Vol 14 (2) ◽

pp. 011-019

Author(s):

Przemysław Brzyski ◽

Stanisław Fic

Keyword(s):

Carbon Dioxide ◽

Construction Industry ◽

Carbon Dioxide Emissions ◽

Industrial Waste ◽

Plant Material ◽

Building Materials ◽

Hydrated Lime ◽

Construction Sector ◽

Industrial Hemp ◽

Reducing Energy

One of the solutions for reducing energy consumption and carbon dioxide emissions in the construction sector is the use of building materials which have a favorable environmental impact. This is possible to achieve by using plant material, e.g., industrial hemp, which absorb large amounts of carbon dioxide during the growth. Instead of cement as a binder there are used alternatively clay or lime modified with industrial waste in the form of pozzolans. The paper presents the possibility of using industrial hemp in the production of composite based on modified hydrated lime. It describes the basic properties of the sample composites such as compressive strength and thermal conductivity based on literature review. The article describes the way of preparing the mixture and the possibility of using the composite for the construction of walls using different techniques.

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Research progress on the preparation of concrete with large amount of iron tailings

E3S Web of Conferences ◽

10.1051/e3sconf/202019801019 ◽

2020 ◽

Vol 198 ◽

pp. 01019

Author(s):

Xiaowei Gu ◽

Haofeng Chi ◽

Jianping Liu ◽

Peng Liu ◽

Ziyang Hu ◽

...

Keyword(s):

Carbon Dioxide ◽

Construction Industry ◽

Carbon Dioxide Emissions ◽

Building Materials ◽

Research Progress ◽

Industrial Solid Waste ◽

The World ◽

Ecological Problems ◽

Sustainable Materials ◽

Main Component

Recently, the use of sustainable materials has gained increasing attention and recognition, especially in the construction industry. As the main component of concrete, ordinary Portland cement (OPC) is undoubtedly one of the most commonly used building materials in the world. However, the manufacture of OPC is accompanied by environmental and ecological problems such as the release of carbon dioxide. According to estimates, about 5%-8% of the world think that carbon dioxide emissions come from the OPC industry, so it is urgent to use fly ash, tailings, slag and other industrial solid waste to produce cement instead of ordinary Portland cement.This article summarizes the achievements of the predecessors and outlines the influence of different iron tailings and iron tailings content on the mechanical properties and durability of concrete.

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Evaluation of the Flexural Performance and CO2 Emissions of the Voided Slab

Advances in Materials Science and Engineering ◽

10.1155/2018/3817580 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 3

Author(s):

Seungho Cho ◽

Seunguk Na

Keyword(s):

Carbon Dioxide ◽

Reinforced Concrete ◽

Yield Strength ◽

Performance Test ◽

Environmental Influence ◽

Concrete Slab ◽

Structural Performance ◽

Reinforcing Bars ◽

Reinforced Concrete Slab ◽

Flexural Performance

Reinforced concrete is regarded as one of the ideal structural materials which comprises concrete with high compressive strength and reinforcing bars with high tensile strength. However, concrete has been pointed out that it consumes a large volume of energy and emits a lot of carbon dioxide during its manufacturing. In order to lower such environmental burdens of concrete structures, a number of studies and approaches have been carried out. The voided slab is also suggested as a new method to reduce the environmental burden since voided section of the slab would use less concrete compared with the normal reinforced concrete slab. However, no studies have evaluated the CO2 emissions and environmental performance of voided slabs. The purpose of this study was to evaluate the structural performance of voided slabs and empirically corroborate their environmental influence. The flexural performance test was carried out based on the variables of the depth of slab, types of the void former materials, and the hollowness ratio. In addition, comparison of the emission of CO2 was also performed by considering the hollowness ratio and types of void former materials over the normal reinforced concrete slab. The structural performance of the voided slab was similar or slightly higher than the normal reinforced concrete slab. The yield strength of specimens was increased approximately 10∼30% over the anticipated yield strength. Based on this result, it is considered that the voided slab would be sufficient to structural performance and beneficial to plane planning in buildings. In general, it is considered that the voided slab would be beneficial to both structural and environmental aspects. However, the test results in this research showed that the voided slab would emit more carbon dioxide emissions compared to the normal reinforced concrete slab. The main source of more CO2 emissions in the voided slab was the anchoring materials. In this research, wires were used to fix the void former materials to the reinforcing bars. In order for the voided slab to become a more eco-friendly and sustainable material, new anchoring methods such as use of recycled materials, new void former materials without anchoring, or other eco-friendly materials should be applied to reduce the emission of CO2.

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Estimation of Carbon Dioxide Emissions from a Traditional Nutrient-Rich Cambodian Diet Food Production System Using Life Cycle Assessment

Sustainability ◽

10.3390/su13073660 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3660

Author(s):

Rathna Hor ◽

Phanna Ly ◽

Agusta Samodra Putra ◽

Riaru Ishizaki ◽

Tofael Ahamed ◽

...

Keyword(s):

Carbon Dioxide ◽

Life Cycle Assessment ◽

Life Cycle ◽

Co2 Emissions ◽

Production System ◽

Agricultural Production ◽

Carbon Dioxide Emissions ◽

Food Production ◽

Carbon Dioxide Co2 ◽

Food Production System

Traditional Cambodian food has higher nutrient balances and is environmentally sustainable compared to conventional diets. However, there is a lack of knowledge and evidence on nutrient intake and the environmental greenness of traditional food at different age distributions. The relationship between nutritional intake and environmental impact can be evaluated using carbon dioxide (CO2) emissions from agricultural production based on life cycle assessment (LCA). The objective of this study was to estimate the CO2 equivalent (eq) emissions from the traditional Cambodian diet using LCA, starting at each agricultural production phase. A one-year food consumption scenario with the traditional diet was established. Five breakfast (BF1–5) and seven lunch and dinner (LD1–7) food sets were consumed at the same rate and compared using LCA. The results showed that BF1 and LD2 had the lowest and highest emissions (0.3 Mt CO2 eq/yr and 1.2 Mt CO2 eq/yr, respectively). The food calories, minerals, and vitamins met the recommended dietary allowance. The country’s existing food production system generates CO2 emissions of 9.7 Mt CO2 eq/yr, with the proposed system reducing these by 28.9% to 6.9 Mt CO2 eq/yr. The change in each food item could decrease emissions depending on the type and quantity of the food set, especially meat and milk consumption.

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Estimating Causal Effects When the Treatment Affects All Subjects Simultaneously: An Application

Big Data and Cognitive Computing ◽

10.3390/bdcc5020022 ◽

2021 ◽

Vol 5 (2) ◽

pp. 22

Author(s):

Chiara Binelli

Keyword(s):

Machine Learning ◽

Carbon Dioxide ◽

Global Warming ◽

Carbon Dioxide Emissions ◽

Control Group ◽

Sources Of Information ◽

Average Global Temperature ◽

Causal Impact ◽

The Impact ◽

Robust Evidence

Several important questions cannot be answered with the standard toolkit of causal inference since all subjects are treated for a given period and thus there is no control group. One example of this type of questions is the impact of carbon dioxide emissions on global warming. In this paper, we address this question using a machine learning method, which allows estimating causal impacts in settings when a randomized experiment is not feasible. We discuss the conditions under which this method can identify a causal impact, and we find that carbon dioxide emissions are responsible for an increase in average global temperature of about 0.3 degrees Celsius between 1961 and 2011. We offer two main contributions. First, we provide one additional application of Machine Learning to answer causal questions of policy relevance. Second, by applying a methodology that relies on few directly testable assumptions and is easy to replicate, we provide robust evidence of the man-made nature of global warming, which could reduce incentives to turn to biased sources of information that fuels climate change skepticism.

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Effect of Urban Heat Island and Global Warming Countermeasures on Heat Release and Carbon Dioxide Emissions from a Detached House

Atmosphere ◽

10.3390/atmos12050572 ◽

2021 ◽

Vol 12 (5) ◽

pp. 572

Author(s):

Daisuke Narumi ◽

Ronnen Levinson ◽

Yoshiyuki Shimoda

Keyword(s):

Carbon Dioxide ◽

Global Warming ◽

Heat Release ◽

Urban Heat Island ◽

Co2 Emissions ◽

Heat Island ◽

Sensible Heat ◽

Heating Season ◽

Urban Heat ◽

Cooling Effects

Urban air temperature rises induced by the urban heat island (UHIE) effect or by global warming (GW) can be beneficial in winter but detrimental in summer. The SCIENCE-Outdoor model was used to simulate changes to sensible heat release and CO2 emissions from buildings yielded by four UHIE countermeasures and five GW countermeasures. This model can evaluate the thermal condition of building envelope surfaces, both inside and outside. The results showed that water-consuming UHIE countermeasures such as evaporative space cooling and roof water showering provided positive effects (decreasing sensible heat release and CO2 emissions related to space conditioning) in summer. Additionally, they had no negative (unwanted cooling) effects in winter since they can be turned off in the heating season. Roof greening can provide the greatest space- conditioning CO2 emissions reductions among four UHIE countermeasures, and it reduces the amount of heat release slightly in the heating season. Since the effect on reducing carbon dioxide (CO2) emissions by UHIE countermeasures is not very significant, it is desirable to introduce GW countermeasures in order to reduce CO2 emissions. The significance of this study is that it constructed the new simulation model SCIENCE-Outdoor and applied it to show the influence of countermeasures upon both heat release and CO2 emissions.

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The travel-related carbon dioxide emissions of atmospheric researchers

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-8-7373-2008 ◽

2008 ◽

Vol 8 (2) ◽

pp. 7373-7389 ◽

Cited By ~ 1

Author(s):

A. Stohl

Keyword(s):

Carbon Dioxide ◽

Co2 Emissions ◽

Information Exchange ◽

Carbon Dioxide Emissions ◽

Radiative Forcing ◽

Global Climate ◽

Air Travel ◽

Ozone Production ◽

Per Capita ◽

Carbon Dioxide Co2

Abstract. Most atmospheric scientists agree that greenhouse gas emissions have already caused significant changes to the global climate system and that these changes will accelerate in the near future. At the same time, atmospheric scientists who – like other scientists – rely on international collaboration and information exchange travel a lot and, thereby, cause substantial emissions of carbon dioxide (CO2). In this paper, the CO2 emissions of the employees working at an atmospheric research institute (the Norwegian Institute for Air Research, NILU) caused by all types of business travel (conference visits, workshops, field campaigns, instrument maintainance, etc.) were calculated for the years 2005–2007. It is estimated that more than 90% of the emissions were caused by air travel, 3% by ground travel and 5% by hotel usage. The travel-related annual emissions were between 1.9 and 2.4 t CO2 per employee or between 3.9 and 5.5 t CO2 per scientist. For comparison, the total annual per capita CO2 emissions are 4.5 t worldwide, 1.2 t for India, 3.8 t for China, 5.9 t for Sweden and 19.1 t for Norway. The travel-related CO2 emissions of a NILU scientist, occurring in 24 days of a year on average, exceed the global average annual per capita emission. Norway's per-capita CO2 emissions are among the highest in the world, mostly because of the emissions from the oil industry. If the emissions per NILU scientist derived in this paper are taken as representative for the average Norwegian researcher, travel by Norwegian scientists would nevertheless account for a substantial 0.2% of Norway's total CO2 emissions. Since most of the travel-related emissions are due to air travel, water vapor emissions, ozone production and contrail formation further increase the relative importance of NILU's travel in terms of radiative forcing.

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