292,833 research outputs found

    AN ECONOMIC ANALYSIS OF THE DAIRY ENVIRONMENTAL COOPERATIVE IN NORTHEAST KANSAS

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    In 1997, the Black Vermillion Dairy Environmental Cooperative (DEC) was started with an EPA 319A grant. Ten Kansas dairies located in the Kansas Black Vermillion Watershed were studied to evaluate the on-farm manure structures cost-shared by the DEC. Net present value (NPV) analysis was used to evaluate the profitability associated with the manure structures. The NPV analysis showed that in most cases, investing in a manure storage structure is a worthwhile venture and can be profitable for the dairy. However, cost-share assistance often will be needed in order to have positive pre-tax and after-tax NPVs.Dairy Environmental Cooperative (DEC), manure management, Net Present Value (NPV) analysis, cost-share, concrete manure storage, Environmental Economics and Policy,

    Multi-scale and multi-physics deterioration modelling for design and assessment of reinforced concrete structures

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    This paper discusses the need for reliable and valid multi-scale and multi-physics prediction models to support the design of new as well as the assessment, maintenance, and repair of existing reinforced concrete structures. A multi-physics and multi-scale deterioration model for chloride-induced corrosion of reinforced concrete has been established. Ongoing work includes extension of the model to 3D as well as modelling of the impact of the steel-concrete interface characteristics and electrochemical potential on chloride thresholds. Identified challenges include, among others, the improved understanding and modelling of single- and multi-deterioration mechanisms, environmental exposure, and data for validation. We envision that next generation maintenance and management of reinforced concrete infrastructure will combine numerical simulations based on multi-scale and multi-physics principles and extensive in-situ monitoring, allowing continuous Bayesian updating of 4D simulations of functional performance

    Towards enhancing sustainable reuse of pre-treated drill cuttings for construction purposes by near-infrared analysis : a review

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    Sustainable reuse of pre-treated drill cuttings (a hazardous waste) as part substitute for fine aggregate in concrete for construction purposes is becoming increasingly attractive; however, issues remain. With recent studies focusing on the use of near-infrared spectroscopic technique for non-invasive determination of chloride concentration in concrete structures, this review examines the applicability of this new technique in the rapid determination of other equally important physicochemical characteristics of concrete produced with this hazardous waste. The nature, source, composition, ecological effects of, and management options for drill cuttings are reviewed. Furthermore, the principles of near-infrared diffuse reflectance spectroscopy are highlighted and lessons from its practical applications in soil science and petrochemical, environmental, and civil engineering are discussed. A framework for a rapid near-infrared analysis of concrete produced with pre-treated drill cuttings for enhanced sustainability as a construction material is also proposed

    Il Progetto EnCoRe : una iniziativa sovranazionale per promuovere il concetto di sostenibilitĂ  del calcestruzzo e dei materiali cementizi

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    Environmental issues are getting more and more relevant in several fields of human activities and the building industry is fully concerned by these concerns. Recycled concrete aggregates (RCA) can be produced by existing concrete members resulting by either industrial processes (i.e., precast structures) or demolitions of existing structures as a whole. Moreover, waste resulting from industrial processes other than the building industry (i.e., production of steel, management of glass, powders resulting from other depuration processes) could be efficiently disposed as concrete aggregates or employed as reinforcement for Fiber-Reinforced Concretes (FRC). The use of natural fibres can also result into an environmentally-friendly and cost-effective solution, especially in developing countries, because of the local availability of raw materials. In order to promote the use of concretes with recycled and/or natural constituents as construction materials, the compatibility between the non conventional constituents and the concrete matrix have to be deeply investigated and correlated to the resulting mechanical and durability properties of the composite. This is the main goal of the EnCoRe Project (www.encore-fp7.unisa.it), a EU-funded initiative, whose activities and main findings will be summarized in this paper

    Repair and corrosion management of reinforced concrete structures

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    The durability of concrete structures is affected by a number of factors such as environmental exposure, electrochemical reactions, mechanical loading, impact damage and others. Of all of these, corrosion of the reinforcement is probably the main cause for the deterioration of steel reinforced concrete (RC) structures. Corrosion management is becoming increasingly necessary as a result of the growing number of ageing infrastructure assets (e.g. bridges, tunnels etc.) and the increased requirement for unplanned maintenance in order to keep these structures operational throughout their design life (and commonly, beyond). The main RC repair, refurbishment and rehabilitation approaches generally employed can be broadly categorised under a) conventional, b) surface treatments, c) electrochemical treatments and d) design solutions. The overarching aim of this research was to identify the key corrosion management techniques and undertake empirical investigations focused on full-scale RC structures to investigate their long-term performance. To achieve this, individual research packages were identified from the above broad five approaches for repair, replacement and rehabilitation. These were 1) Patch repairs and incipient anodes, 2) Impressed Current Cathodic Protection, 3) Galvanic Cathodic Protection and 4) Hydrophobic treatments. The selection of the above research packages was based on past and present use by the construction industry to repair, refurbish and rehabilitate RC structures. Their contributions may be broadly categorised as i) Investigations on how specific treatments and materials perform, ii) Investigations on the effectiveness of existing methods of measurements and developing alternatives, iii) Changes to the existing theory of corrosion initiation and arrest and iv) Changes to management framework strategies. The key findings from each research package can be summarised as follows: Macrocell activity appears to be a consequence rather than a cause of incipient anode formation in repaired concrete structures, as has previously been presented; ICCP has persistent protective effects even after interruption of the protective current; Discrete galvanic anodes installed in the parent concrete surrounding the patch repair are a feasible alternative to galvanic anodes embedded within the patch repairs of RC structures; Silanes may have a residual hydrophobic effect even after 20 years of service

    Life cycle management of concrete structures based on sustainability indicators

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    A concrete structure should be sufficiently planned, designed, executed and maintained to ensure its requirements during the life cycle. However, structures suffering from serious deterioration in structural members and sometimes subsequent loss in sustainability have been often found due to various reasons. One of the reasons is lack of total management for the structure. To meet these facts, it is extremely important to pursue coordination of engineering work in the design, execution and maintenance stages. The life cycle management is an organized system to support engineers decision to realize sufficient sustainability of the structure in the design, execution, maintenance, and all related work during its life cycle. The life cycle management is implemented based according to the life cycle management scenario in which balance of several sustainability indicators should be considered with ensuring overall sustainability. The sustainability indicators will be determined from the social, environmental and economic points of view. The scenario should be regularly reviewed based on the PDCA cycle and be updated if necessary. This paper deals with the concept and framework of the life cycle management of concrete structures to ensure sustainability during the structural life

    Probabilistic and predictive performance-based approach for assessing reinforced concrete structures lifetime: The applet project

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    International audienceConcrete deterioration results in different damage extents, from cracking to concrete spalling, from losses of reinforcement cross-sections to bond losses. A relevant prediction of this performance is the basis for a successful management of the concrete structures. Conversely, the large amount of uncertainties related to parameters and models require a specific analysis in order to provide relevant results. The APPLET project intends to develop a probabilistic and predictive performance-based approach by quantifying the various sources of variability (material and structure), studying the interaction between environmental aggressive agents and the concrete material, ensuring a transfer of the physical-chemical models at the material scale towards models at the structure level, including and understanding in a better manner the corrosion process, integrating interface models between reinforcement and concrete, proposing relevant numerical models, integrating know-how from monitoring or inspection. To provide answers, a consortium of 19 partners has been established and has promoted a research project funded by the French Research Science Agency (ANR). Started in May 2007, the project has ended in November 2010. This paper will resume the most significant advances targeted by this research project

    The sustainable energy approach in the manufacture of cellular concrete

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    Cellular concrete holds one of the leading places in world practice of construction as a structural heat insulating material used in the construction and reconstruction of buildings and structures for various purposes. Excessive (reserve) porosity of cellular concrete provides its frost resistance (compensates expansion of water when freezing and the formed ice without destroying the material). Vapor permeability of cellular concrete provides fast removal of technological moisture from the material and the maintenance of normal moisture conditions in the rooms, and rather high air permeability contributes to the preservation of fresh air in the rooms. Thermal insulation and strength properties of cellular concrete allow erecting single-layer enclosing structures with the required thermal resistance from it. Cellular concretes are divided into aerated concrete and foam concrete, the operating, physical and mechanical parameters of which are almost the same with all other things being equal. According to the hydrothermal treatment method, cellular concrete is divided into two groups: autoclaved and non-autoclaved concrete (air hardening or steaming). The qualities of such concretes differ significantly, since autoclave treatment changes the mineralogical composition of concrete, which greatly affects the profitability of energy-related technological processes associated with the environment and ultimately forms the basis of environmental planning and management

    Comparative LCA of concrete with recycled aggregates: a circular economy mindset in Europe

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    [EN] Purpose Construction and demolition waste (C&DW) is the largest waste stream in the European Union (EU) and all over the world. Proper management of C&DW and recycled materialsÂżincluding the correct handling of hazardous wasteÂżcan have major benefits in terms of sustainability and the quality of life. The Waste Framework Directive 2008/98/EC aims to have 70% of C&DW recycled by 2020. However, except for a few EU countries, only about 50% of C&DW is currently being recycled. In the present research, the environmental impact of concrete with recycled aggregates and with geopolymer mixtures is analysed. The aim of the present research is to propose a comparative LCA of concrete with recycled aggregates in the context of European politics. Methods Life cycle assessment (LCA) methodology is applied using Simapro© software. A cradle to grave analysis is carried out. The results are analysed based on the database Ecoinvent 3.3 and Impact 2002+. Results Results show that the concrete with 25% recycled aggregates is the best solution from an environmental point of view. Furthermore, geopolymer mixtures could be a valid alternative to reduce the phenomenon of Âżglobal warmingÂż; however, the production of sodium silicate and sodium hydroxide has a great environmental impact. Conclusions A possible future implementation of the present study is certainly to carry out an overall assessment and to determine the most cost-effective option among the different competing alternatives through the life cycle cost analysis.Colangelo, F.; GĂłmez-Navarro, T.; Farina, I.; Petrillo, A. (2020). Comparative LCA of concrete with recycled aggregates: a circular economy mindset in Europe. International Journal of Life Cycle Assessment. 25(9):1790-1804. https://doi.org/10.1007/s11367-020-01798-6S17901804259Akhtar A, Sarmah (2018) Construction and demolition waste generation and properties of recycled aggregate concrete: a global perspective. J Cleaner Prod 186:262–281Bare JC, Hofstetter P, Penningtonne DW, Helias A, de Haes U (2000) Midpoints versus endpoints: the sacrifices and benefits. Int J Life Cycle Assess 5(6):319–326Blengini GA, Garbarino E (2010) Resources and waste management in Turin (Italy): the role of recycled aggregates in the sustainable supply mix. J Clean Prod 18(10–11):1021–1030Blengini GA, Garbarino E, Ć olar S, Shields DJ, HĂĄmor T, Vinai R, Agioutantis Z (2012) Life cycle assessment guidelines for the sustainable production and recycling of aggregates: the sustainable aggregates resource management project (SARMa). J Clean Prod 27:177–181Blengini GA, Garbarino E, Bevilacqua P (2017) Sustainability and integration between mineral resources and C&DW management: overview of key issues towards a resource-efficient Europe. Env Eng Man J 16(2):493–502Borghi G, Pantini S, Rigamonti L (2018) Life cycle assessment of non-hazardous construction and demolition waste (CDW) management in Lombardy region (Italy). J Clean Prod 184:815–825Braga AM, Silvestre JD, de Brito J (2017) Compared environmental and economic impact from cradle to gate of concrete with natural and recycled coarse aggregates. J Clean Prod 162:529–543Chen C, Habert G, Bouzidi Y, Jullien A, Ventura A (2010) LCA allocation procedure used as an incitative method for waste recycling: an application to mineral additions in concrete. Res Con Rec 54(12):1231–1240Chen Z, Gu H, Bergman RD, Liang S (2020) Comparative life-cycle assessment of a high-rise mass timber building with an equivalent reinforced concrete alternative using the Athena impact estimator for buildings. Sustainability (Switzerland) 12(11):4708Colangelo F, Cioffi R (2017) Mechanical properties and durability of mortar containing fine fraction of demolition wastes produced by selective demolition in South Italy. Comp Part B: Eng 115:43–50Colangelo F, Petrillo A, Cioffi R, Borrelli C, Forcina A (2018a) Life cycle assessment of recycled concretes: a case study in southern Italy. Sci Total Env 615:1506–1517Colangelo F, Forcina A, Farina I, Petrillo A (2018b) Life cycle assessment (LCA) of different kinds of concrete containing waste for sustainable construction. Buildings 8(5):70Colangelo F, Navarro TG, Petrillo A, Farina I, Cioffi R (2020) Life-cycle impact of concrete with recycled materials. Encyclopedia of Renewable and Sustainable Materials, Volume 5(2020):414–421COM (2012) 433, COMMUNICATION FROM THE COMMISSION TO THE EUROPEAN PARLIAMENT AND THE COUNCIL Strategy for the sustainable competitiveness of the construction sector and its enterprises, http://eur-lex.europa.eu/procedure/EN/201859, Brussels, 31.7.2012, COM(2012) 433 finalCOM (2014) 445, COMMUNICATION FROM THE COMMISSION TO THE EUROPEAN PARLIAMENT AND THE COUNCIL, http://ec.europa.eu/environment/eussd/pdf/SustainableBuildingsCommunication.pdf, Brussels, 1.7.2014 COM(2014) 445 finalDavidovits J (2018) Geopolymers based on natural and synthetic metakaolin a critical review. Ceramic Eng Science Proc 38(3):201–214Di Maria A, Eyckmans J, Van Acker K (2018) Downcycling versus recycling of construction and demolition waste: combining LCA and LCC to support sustainable policy making. Waste Man 75:3–21Directive 2008/98/EC on waste (Waste Framework Directive), http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32008L0098EN 1992-1-1:(2004) Eurocode 2: Design of concrete structures - Part 1–1: General rules and rules for buildingsEstanqueiro B, Dinis Silvestre J, de Brito J, Duarte Pinheiro M (2018) Environmental life cycle assessment of coarse natural and recycled aggregates for concrete. Eur J Env Civ Eng 22(4):429–449Etxeberria M, VĂĄzquez E, MarĂ­ A, Barra M (2007) Influence of amount of recycled coarse aggregates and production process on properties of recycled aggregate concrete. Cem Conc Res 37(5):735–742EU construction & demolition waste management protocol (2016) BrusselsGĂĄlvez-Martos J-L, Styles D, Schoenberger H, Zeschmar-Lahl B (2018) Construction and demolition waste best management practice in Europe. Res Con Rec 136:166–178Gluth, G.J.G., Arbi, K., Bernal, S.A., Bondar, D., Castel, A., Chithiraputhiran, S., Dehghan, A., Dombrowski-Daube, K., Dubey, A., Ducman, V., Peterson, K., Pipilikaki, P., Valcke, S.L.A., Ye, G., Hajimohammadi, A., van Deventer, J.S.J., 2017. Characterisation of one-part geopolymer binders made from fly ash. Waste Biom Val, 8(1), pp. 225–233Gomes R, Silvestre JD, de Brito J (2020) Environmental, economic and energy life cycle assessment “from cradle to cradle” (3E-C2C) of flat roofs. Journal of Building Engineering 32:101436ISO 14040 (2006) Environmental management life cycle assessment. Principles and Framework. ISO, GenevaISO 14044 (2006) Environmental management. Life cycle assessment. Requirements and Guidelines. ISO, GenevaJafary Nasab T, Monavari SM, Jozi SA, Majedi H (2020) Assessment of carbon footprint in the construction phase of high-rise constructions in Tehran. Int J Environ Sci Technol 17(6):3153–3164Jolliet O, Margni M, Charles R, Humbert S, Payet J, Rebitzer G, Rosenbaum R (2003) Impact 2002+: a new life cycle impact assessment methodology. Int J Life Cycle Assess 8(6):324–333Khan MW, Ali Y, De Felice F, Salman A, Petrillo A (2019) Impact of brick kilns industry on environment and human health in Pakistan. Sci Total Environ 678:383–389Knoeri C, SanyĂ©-Mengual E, Althaus H-J (2013) Comparative LCA of recycled and conventional concrete for structural applications. Int J Life Cycle Assess 18(5):909–918Lu W, Yan H (2011) A framework for understanding waste management studies in construction. Waste Man 31:1252–1260Marinković S, Radonjanin V, MaleĆĄev M, Ignjatović I (2010) Comparative environmental assessment of natural and recycled aggregate concrete. Waste Man 30(11):2255–2264Mercante IT, Bovea MD, Ibåñez-ForĂ©s V, Arena AP (2012) Life cycle assessment of construction and demolition waste management systems: a Spanish case study. Int J Life Cycle Assess 17(2):232–241Pantini S, Giurato M, Rigamonti L (2019) A LCA study to investigate resource-efficient strategies for managing post-consumer gypsum waste in Lombardy region (Italy). Res Con Rec 147:157–168Petrillo A, Cioffi R, De Felice F, Colangelo F, Borrelli C (2016) An environmental evaluation: a comparison between geopolymer and OPC concrete paving blocks manufacturing process in Italy. Env Prog Sus Energy 35(6):1699–1708Provis JL (2017) Alkali-activated cementitious materials and concretes - steps towards standardization, American Concrete Inst, ACI Special Publication 2017-January (SP 320), pp. 444-448Sayagh S, Ventura A, Hoang T, François D (2010) Sensitivity of the LCA allocation procedure for BFS recycled into pavement structures. Res cons rec 54(6):348–358Tangtinthai N, Heidrich O, Manning DAC (2019) Role of policy in managing mined resources for construction in Europe and emerging economies. J Env Man 236:613–621ToĆĄić N, Marinković S, DaĆĄić T, Stanić M (2015) Multicriteria optimization of natural and recycled aggregate concrete for structural use. J Clean Prod 87(1):766–776Van den Heede P, De Belie N (2012) Environmental impact and life cycle assessment (LCA) of traditional and ‘green’ concretes: literature review and theoretical calculations. Cem Conc Comp 34(4):431–442Vossberg C, Mason-Jones K, Cohen B (2014) An energetic life cycle assessment of C&D waste and container glass recycling in Cape Town, South Africa. Res Con Rec 88:39–49Walling SA, Notman S, Watts P, Govan N, Provis JL (2019) Portland cement based immobilization/destruction of chemical weapon agent degradation products. Industrial Eng Chemistry Res 58(24):10383–10393Wu H, Zuo J, Yuan H, Zillante G, Wang J (2019) A review of performance assessment methods for construction and demolition waste management. Res Cons Recycling 150:104407Zhang C, Hu M, Dong L, Gebremariam A, Mirand-Xicotencatl B, Di Maio F, Tukker A (2019) Eco-efficiency assessment of technological innovations in high-grade concrete recycling. Res Cons Recycling 149:649–66
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