FACULTY OF CIVIL ENGINEERING. Eng. Claudiu Aciu. Ph.D. THESIS ECOLOGICAL MATERIALS IN STRUCTURAL AND NON-STRUCTURAL ELEMENTS IN DWELLING BUILDINGS

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1 FACULTY OF CIVIL ENGINEERING Eng. Claudiu Aciu Ph.D. THESIS ECOLOGICAL MATERIALS IN STRUCTURAL AND NON-STRUCTURAL ELEMENTS IN DWELLING BUILDINGS ABSTRACT PhD SUPERVISOR, Prof.dr.eng. Mariana BRUMARU 2009

2 CONTENTS Chapter 1. BUILDING MATERIALS IN THE PERSPECTIVE OF SUSTAINABLE DEVELOPMENT...1 Chapter 2. CRITERIA FOR THE EVALUATION OF BUILDING MATERIALS FROM AN ECOLOGICAL POINT OF VIEW...1 Chapter 3. BUILDING MATERIALS IN THE ECOLOGICAL PERSPECTIVE...2 Chapter 4. REDUCTION OF THE ENVIRONMENTAL IMPACT OF BUILDING MATERIALS...3 Chapter 5. LIFE CYCLE ASSESSMENT OF MATERIALS...4 Chapter 6. THE ECCOMAT 09 METHOD AND SOFTWARE FOR THE SELECTION OF ECOLOGICAL BUILDING MATERIALS...5 Chapter 7. FINAL CONCLUSIONS...6 SELECTIVE REFERENCES...8

3 Chapter 1. BUILDING MATERIALS IN THE PERSPECTIVE OF SUSTAINABLE DEVELOPMENT Sustainable development is a strategy that provides a framework within which communities try to find economic development modalities based on the effective use of resources, on new commercial activities in order to consolidate economy, while protecting and improving the environment. Sustainable development in the field of civil engineering requires the attainment of several objectives, of which the most important are: - reduction of the use of conventional energy sources (fossil fuels) and use of renewable energy sources; - conservation of natural areas and biodiversity; - insurance of a healthy interior environment; - use of ecological materials. Particularly important in achieving these objectives is the selection of ecological building materials and the production of new ecological materials according to the requirements of sustainable development. In order to avoid the negative impact on the environment, the process of design and production of ecological materials should take into consideration the effects of the following factors that occur during the life cycle of these materials: the energy consumed in the extraction, manufacture, transport, construction processes; the degree of environmental damage caused by the extraction of materials; the amount of waste generated during the extraction and manufacturing processes; the amount of pollutants resulting from the extraction, manufacture, construction, demolition processes; pollution as an effect of the storage of materials resulting from demolition; the volume of ultimate waste; the percentage of recyclable or reusable material; the durability of the material and its effects on the life duration of the building. There are no ideal solutions regarding the construction methods and there are no purely ecological materials, but a correct, well documented analysis will facilitate a more friendly/favorable result in relation to the environment. The selection of the material with optimal construction characteristics for a specific use requires a multicriteria analysis of all factors with a negative impact on the environment. Chapter 2. CRITERIA FOR THE EVALUATION OF BUILDING MATERIALS FROM AN ECOLOGICAL POINT OF VIEW In the present context, the entire building industry is facing special priorities regarding the execution of ecological constructions. For this purpose, both material manufacturers and builders should take into account as early as the design stage the factors that influence the quality of the environment during the life cycle of the materials, considering the following criteria: - 1 -

4 The criterion or resources, which establishes the adequacy of the use of material resources, taking into account their amount, the possibility of their renewal, their spatial position in relation to the location of their processing or use. The criterion of topographic change is closely related to the criterion of resources, its importance consisting in the requirement of the conservation of natural systems. Economic development resulting in necessary topographic changes in an area should not irreversibly affect natural ecological balance. The criterion of waste and its recycling is important from two essential points of view: the environmental impact and the embodied energy. This criterion should be considered as early as the stage of the elaboration of the feasibility study and design. The criterion of pollution is related to those processes of manufacture of building materials that have negative effects on the environment (global heating, acidification, reduction of the ozone layer, etc.). This criterion requires the finding and the use of the building materials with the lowest impact on the environment. The energy criterion incorporates the energy requirements for the life cycle of a building. Since energy production affects both, natural resources and the environment through the resulting pollutants, the energy criterion is one of the most important criteria that should be taken into account in the building industry. The indicators by which this criterion is relevantly defined are the embodied energy in building materials and systems and the operating energy. The biological criterion takes into account the effects of materials on the health of people during the life cycle of building materials. The knowledge of the risks that old and modern building materials pose to health is essential in order to ensure the protection of workers and users. Chapter 3. BUILDING MATERIALS IN THE ECOLOGICAL PERSPECTIVE An analysis of materials that are frequently used in construction from the point of view of the embodied energy, of the resources from which they are derived and their availability, as well as their effects on health, focuses the attention of specialists on the discovery of new materials, manufacturing technologies and building systems. An increase in the interest in the use of traditional materials such as earth, wood, straw etc., as well as new building materials and systems such as insulating concrete forms, autoclaved cellular concrete and even metal products combined with thermal and sound insulating materials is seen. From an ecological point of view, an ideal building material would be one for which the raw material is found in nature and needs no or low processing, its manufacturing energy is derived from renewable sources and after use it is completely recycled. Clay bricks are building materials that largely meet these requirements. Their manufacture uses raw material that is abundantly available, the incorporated energy - 2 -

5 is extremely low considering that solar energy is used, and after demolition they can be easily reintegrated into the natural circuit. Ceramic blocks are made of raw materials that are found in sufficient amounts in the terrestrial crust; although some of them have a high amount of embodied energy, they are successfully used in construction due to their mechanical and thermo-physical properties. They have no negative effects on health. Wood is an abundant renewable ecological material which, due to its physicalmechanical properties and multiple technical-economic advantages, is increasingly used in many countries, in a large variety of products (logs, plywood, chipboard, glued laminated timber, etc.). Modern wood materials are obtained by a change in the composition and the structure of wood material and have superior technical characteristics. Their manufacturing technology involves an increased amount of embodied energy, which however remains within reasonable limits. Metals are materials with a major impact on the environment from an ecological point of view, because the manufacturing process involves high energy consumption. Although the embodied energy is considerable, they are durable building materials, with a long life cycle, at the end of which recycling can be successfully performed, contributing in this way to the reduction of the amount of raw materials and energy required for new constructions. Thermal insulating materials used in construction, although high energy consumers, have an increased ecological value due to the reduction of operating energy. In the context of an effective use of raw material resources and of a reduction in pollution, the manufacture of new effective ecological building materials involves the good management of material and energy resources. Chapter 4. REDUCTION OF THE ENVIRONMENTAL IMPACT OF BUILDING MATERIALS The main solutions regarding the reduction of the environmental impact of building materials are: - the rational and effective use of raw materials; - reduction of the amount of embodied energy; - waste management; - manufacture of new ecological building materials; Some of the ways of achievement of these objectives are: - selection of optimal building materials (for their specific use) so that the energy incorporated in the building systems should be as low as possible; - minimization of the required operating energy; - adequate management of waste material, based on the effective material and energy use and the reduction of the stored waste; - 3 -

6 - energetic valorization of waste, achievable by the replacement of fossil fuels used in the manufacturing of cement with alternative fuels derived from waste or various technological processes (worn tires, plastics, Profuel, Cemfuel, etc.); - use of waste as materials, which eventually means an effective energy use, achievable by: recycling of materials with high embodied energy (e.g. metals); recycling of waste with a view to their use in concrete industry as: aggregate substitutes (rice husks, sawdust, coconut pith, cork granules, crushed concrete, broken bricks etc.), Portland cement substitutes (thermal power station ash, blast furnace slag, rice husk ash, etc.); recycling of waste for the production of new ecological materials (e.g. straw products, bricks made of paper fibers agglomerated with cement, sludge-based mortars). Chapter 5. LIFE CYCLE ASSESSMENT OF MATERIALS From an ecological point of view, building materials should be considered in terms of their potential effects and impact on the environment during their life cycle. The aim of life cycle assessment in the case of building materials is in the first place to compare the environmental impact of different products that have the same use. LCA can also be used as a decision-making instrument in the design of new products. The evaluation of the environmental effects of materials can be performed by various methods for impact analysis. The methods and programs for the analysis of materials from an ecological point of view are in a continuous development process, each having a number of advantages and disadvantages. The method of the critical volume is easy and comfortable to use for the assessment of ecological impact relying on the norms in force, but is defective because norms change in time and differ from one country to another. CML-2 is an adequate method for the life cycle assessment of a product or process, allowing the evaluation and the interpretation of results based on analysis methods such as: dominance analysis, hierarchical elimination analysis, qualitative or quantitative multicriteria analysis. The method of qualitative environmental protection numbers (kv) is a relatively practical method, based on which the designer obtains accurate information on the best material for a specific use, assessed from an ecological point of view; however, the method is qualitatively subjective. The building material selection guide presents a large amount of information and gives the designer indications about the technical conditions, the alternatives of use of materials, the recovery of waste, the environmental and health problems raised by the different materials. However, the large amount of information poses particular problems to the designer regarding the choice of the material with optimal characteristics

7 Both the methods and the programs are focused on the analysis of materials only regarding the environmental effects and possibly the costs involved, without approaching other criteria that are absolutely necessary for sustainable development. This has generated the idea of finding a method for the analysis of materials that might respond to these requirements. Such a method is ECCOMAT 09. Chapter 6. THE ECCOMAT 09 METHOD AND SOFTWARE FOR THE SELECTION OF ECOLOGICAL BUILDING MATERIALS ECCOMAT 09 is a multicriteria analysis method for the selection of the optimal ecological material from a large number of materials for the same use. The field of application is the design and execution of buildings with ecological materials and the extension of research in order to obtain new ecological materials. The analysis concerns ecological, hygro-thermal comfort characteristics, mechanical strengths and costs. From an ecological point of view, the greenhouse effect, acidification, eutrophication, toxicity effects as well as waste management are analyzed. Environmental impact is assessed based on the material-energy balance, taking into account the energy incorporated in materials and fuel consumption for transportation. The evaluation of hygro-thermal comfort is performed by taking into consideration the following thermo-technical characteristics of materials: specific heat; thermal conductivity; the vapor permeability resistance factor; thermal diffusivity. Using an improved multicriteria analysis with a scoring system proportional to the value of effects, the program gives the best solution based on which designers and researchers in the field of construction can make adequate decisions. The ECCOMAT 09 analysis of building materials gives a concrete answer to the designer regarding the material with optimal characteristics for the construction of a building depending on its use. The researcher involved in the production of a new building material has the possibility to discover the weak links in the life cycle of the product, having recourse to the analysis of the characteristics of the raw and other materials required for hygro-thermal comfort, resistance and environmental protection (including waste management). The calculation program based on the ECCOMAT 09 analysis method is an instrument that offers the users many possibilities for the management and the assessment of building materials, helping them obtain the optimal solution in an easy and rapid way. The ECCOMAT 09 program has the following characteristic elements: an intuitive user interface based on ISO 14040; easy parameterized modeling, with analysis based on scenarios of importance of criteria categories; compilation of life cycle inventories using the in-house data including the data introduced by the user; - 5 -

8 reporting of data in a number of different ways by the use of table/graphic display options with comparative values for different materials depending on the chosen parameters; input output data base program; classification of results; extensive filtering options for all results. Chapter 7. FINAL CONCLUSIONS In the context of sustainable development, it is necessary to define ecological materials in the first place. Given the fact that this requires the consideration of a large number of factors referring to both, the negative environmental effects of materials and their potential risks on health, the establishment of well-defined criteria, allowing the objective characterization of building materials, is needed. In this context, the following criteria have been defined: The criterion of resources; The criterion of topographic change; The criterion of waste and recycling; The criterion of pollution The energy criterion; The biological criterion. Considering these criteria, a large number of materials that are frequently used in construction have been analyzed and compared. It has been found that the energy criterion is present in all the stages of the life cycle of materials. This evidences the importance of the energy incorporated in building materials and their transportation. Next, the problem of the possibilities of reducing the environmental impact of building materials has been approached. A number of solutions have been identified which are intended for the reduction of the embodied energy, the reduction of raw material and fossil fuel consumption, the recovery of the energy incorporated in the manufacturing process of new materials, through waste recycling and the use of secondary products resulting from other technological processes. At present, the optimal method that analyzes the potential environmental impact of a product during its life cycle is the Life Cycle Assessment, whose principles are established by the ISO standards. This method can be perfectly applied to building materials as it is shown in Chapter 5 of the thesis, but this is not sufficient to solve the designer's problem of choosing the optimal material for a sustainable building. This shows that the finding of a practical method to help designers cope with the large amount of information available is important and necessary. This method is the ECCOMAT-09, which gives the optimal solution by a multicriteria analysis, by assessing materials from an ecological point of view and from the point of view of hygro-thermal criteria, durability criteria and costs. In order to create a practical instrument for both, the designer and the manufacturer, based on the ECCOMAT-09 method, a program with the same name - 6 -

9 has been devised. The case studies performed using this program for different groups of materials show the importance of the use of the building which influences the weight of the criteria taken into consideration. This allows, using the data base set up by the administrator, to determine from a large group of building materials, in an easy and rapid way, the material with optimal characteristics for the construction of a building for a specific use. The program is also extremely useful to building materials manufacturers, who can verify their products by having recourse to the facility made available by the program, which permits detailed analyses on environmental impact, thermo-technical characteristics, strengths, and costs. The program allows the development of the existing data base through the contribution of both the administrator and the user by the addition of new materials. The program can be easily updated, according to the latest findings in the field. A synthesis of what has already been presented in this thesis can evidence the following personal contributions: a) a detailed analysis of factors that play a role in the life cycle of building materials with negative environmental effects ; b) a clear definition of the criteria for the ecological assessment of building materials; c) the study on the ecological impact and the potential effects on health of some currently used building materials; d) the presentation of modern solutions for the reduction of the negative environmental impact of some building materials; e) the research performed in the Laboratory of Building Materials of the Faculty of Civil Engineering of the TU of Cluj-Napoca regarding the possibilities of using the Mechel sludge in the composition of some mortars; f) the life cycle assessment (LCA) of building materials and the analysis of their impact on the environment; g) the study on the methods and programs for the selection of the optimal building material for the construction of a certain structure; h) the elaboration of a multicriteria analysis method for the selection of the optimal ecological material from a large number of materials for the same use; i) the elaboration of the calculation program based on the above mentioned multicriteria method an instrument that offers the users many possibilities for the management and the assessment of building materials and helps them obtain in a rapid and pragmatic way the optimal solution. The program makes available to the user, in an easy and rapid way, useful information on: - the assessment of the environmental impact of materials from the point of view of greenhouse, acidification, eutrophication, toxicity effects and waste management; - the assessment of materials in terms of their thermo-technical characteristics; - the assessment of materials from the point of view of their mechanical strengths; - the assessment and the classification of materials following the analysis performed, taking into consideration all criteria, including costs, which provides the optimal solution

10 SELECTIVE REFERENCES 1. Aciu, C., Brumaru, M.: Sustainable building design, construction, use and demolition. Acta Technica Napocensis. Civil engineering Architecture. Nr. 51, Aciu, C., Józsa, Zs. (advisor): Studies on use of lime milk neutralization sludge in the building material industry, Proceedings of the fib Congress Innovative materials and technologies for concrete structures ; Budapest, Hungary September Althaus, H.J., Kellenberger, D., Doka, G., Künniger, T.: Manufacturing and disposal of building materials and inventorying infrastructure in ecoinvent. Int J LCA, 10(1), 2005, pp Badea, A., Apostol, T., Dincă, C.: Evaluarea impactului asupra mediului utilizând analiza ciclului de viaţă, Ed. Politehnica Press, Bucureşti, Berge, B.: The ecology of building materials. Oxford : Butterworth- Heinemann, ISBN Bold, O.V., Mărăcineanu, G.A.: Depozitarea, tratarea şi reciclarea deşeurilor şi materialelor, Ed. Matrix Rom, Bucureşti, Curwell, S., Fox, B.: Hazardous building materials: A guide to the selection of environmentally responsible alternatives, Ed. Spon Press, London, Erlandsson, M., Borg, M.: Generic LCA-methodology applicable for buildings, constructions and operation services - today practice and development needs. Building and Environment 38, 2003, p Froeschle, L.: Environmental assessment and specification of green building materials Gheorghe, M.: Valorificarea deşeurilor şi subproduselor industriale în construcţii, Editura Matrix Rom, Bucureşti, Guvernul României, Ministerul Mediului şi Dezvoltării Durabile. Strategia Naţională pentru Dezvoltare Durabilă a României Orizonturi Ed. Green Partners, Bucureşti, Hammond, G.P., Jones, C.I.: Embodied energy and carbon in construction materials, University of Bath, UK, Hansen, H., Zöld, A.: Ecobuild Environmentally friendly construction and building, Project co-ordinator Horsens Polytechnic, Denmark, Ianculescu, S., Nisipeanu, S., Ştepa, R.: Managementul mediului în conformitate cu seria ISO 14000, Ed. Matrix Rom, Bucureşti, Kibert, C.J.: Sustainable construction: Green building design and delivery, Ed. John Wiley & Sons, New Jersey, Lippke, B.: Building Materials and Climate Change Lynne, E.L., Adams, C.: Alternative construction: Contemporary natural building methods, Ed. John Wiley & Sons, New York, Meukam, P., Jannot, Y., Noumowe, A., Kofane, T.C.: Thermo physical characteristics of economical building materials. Construction and Building Materials, 18, 2004, pp Roşu, L., Florea, M.: Legislaţia mediului, Ed. Matrix Rom, Bucureşti, Roulet, C.A.: Santé et qualité de l'environnement intérieur dans les bâtiments, Ed. Presses Polytechniques et Universitaires Romandes,

11 21. Rusu, T., Bejan, M.: Deşeul sursă de venit, Ed. Mediamira, Cluj-Napoca, Sjunnesson, J.: Life cycle assessment of concrete, Master thesis, Spiegel, R., Meadows, Dru: Green building materials: A guide to product selection and specification, Ed. John Wiley & Sons, London, Stan, D.: Construcţii şi mediu, Ed. Matrix Rom, Bucureşti, Ţuţuianu, O.: Evaluarea şi raportarea performanţelor de mediu, Indicatori de mediu, Ed. AGIR, Bucureşti, Ungureanu, C.: Contribuţii la proiectarea construcţiilor civile în cadrul conceptului de dezvoltare durabilă. Teză de doctorat, Iaşi, Watts, K., Wilkie, K., Thompson, K., Corson, J.: Thermal and mechanical properties of straw bales as they relate to a straw house Canadian Society of Agricultural Engineering Paper No , Ottawa, Ontario, *** Easy guide to eco-building: Design, build and live with the environment *** SR EN ISO Management de mediu, Evaluarea ciclului de viaţă. Principii şi cadru de lucru. 30. *** SR ISO Management de mediu, Evaluarea ciclului de viaţă. Definirea scopului, domeniului de aplicare şi analiza de inventar. 31. *** SR EN Atmosfera locului de muncă. Ghid pentru aplicarea şi utilizarea procedurilor de evaluare a expunerii la agenţi chimici şi biologici. 32. *** SR EN ISO Management de mediu. Evaluarea ciclului de viaţă. Interpretarea ciclului de viata. 33. *** SR ISO Gaze cu efect de seră; Partea 1: Specificaţii şi ghid, la nivel de organizaţie, pentru cuantificarea şi raportarea emisiilor şi a cantităţilor îndepărtate de gaze cu efect de seră