TY - CONF A1 - Weimann, Karin A1 - Adam, Christian ED - Martins, Isabel ED - Ulsen, Carina ED - Angulo, Sergio Cirelli T1 - Secondary building materials from construction and demolition waste: environmental benefits and costs T2 - Progress of recycling in the built environment N2 - Due to the large quantities of construction and demolition waste (CDW) in Europe, its reuse or recycling is of particular importance. Although several countries already recycle high amounts of CDW, the use as secondary raw materials is often limited by inferior building material properties. Specific characteristics, like high porosity and low density are caused by hardened cement paste in crushed concrete and the content of mortar and plaster in brick debris. Impurities like wood or gypsum and also harmful substances like organic pollutants may be a major problem for a reuse and should be minimized. Therefore unwanted materials and impairing substances have to be separated from the secondary building material stream. This can be done during the demolition process by using techniques for selective dismantling or during the subsequent treatment of the resulting rubble. Since almost all processing steps are associated with environmental impacts, the benefits of saving natural resources by applying secondary building materials should be weighed carefully. An environmental performance evaluation was undertaken to assess different techniques for reducing gypsum in recycled concrete aggregates, aiming at a minimization of elutable sulfates. These results were compared to the environmental impacts of the extraction of natural aggregates for concrete. T2 - "Progress of recycling in the built environment" CY - Sao Paulo, Brazil DA - 03.08.2015 KW - CDW processing KW - Demolition/selective dismantling KW - Gypsum KW - Environmental evaluation KW - Bauschuttaufbereitung KW - Ökobilanzielle Bewertung PY - 2015 UR - http://www.rilem.org/gene/main.php?base=500218&id_publication=449&id_papier=10699 SN - e-ISBN: 978-2-35158-158-2 SP - 192 EP - 199 CY - Paris, France AN - OPUS4-38170 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weimann, Karin A1 - Adam, Christian ED - Jones, Roderick ED - Newlands, Moray D. ED - Halliday, Judith E. ED - Csetenyi, Lszlo J. ED - Zheng, Li ED - McCarthy, Michael J. ED - Dyer, Thomas D. T1 - Sustainability in the production of Recycled Concrete Aggregates T2 - Environment, Efficiency and Economic Challenges for Concrete N2 - Concrete is one of the most widely used construction materials and, accordingly, the concrete industry is an important stakeholder in the field of sustainable construction. Therefore various approaches have been implemented to increase the sustainability of concrete. Besides reducing CO2-emissions during cement production, increasing the energy efficiency of buildings and extending their life span, the end-of-life performance of concrete is also an essential aspect of sustainability. Reusing concrete as a secondary building material meets the requirements of sustainability in several ways: the extended time availability of primary raw materials and, thereby, the protection of natural resources as well as conserving landfill site. Furthermore, the production of recycled concrete aggregates (RCA) is a good example for closed-loop recycling. However, regarding the use of RCA as a substitute for natural aggregates in concrete, attention must be paid to all issues of sustainability: this means that environmental, economic and social aspects have to be considered. Since RCA generally have inferior building material properties, such as higher porosity and lower density, the implementation of closed-loop recycling of concrete only makes sense if the technical quality assurance is secured. This paper focusses on the implementation of techniques for the deconstruction/demolition of buildings and the subsequent treatment of concrete rubble in order to improve the building material properties of RCA with regard to the requirements of sustainability and also technical rules and standards. T2 - The 9th International Concrete Conference CY - Dundee, UK DA - 04.07.2016 KW - RCA (Recycled concrete aggregates) KW - Gypsum KW - Selective dismantling KW - CDW treatment KW - Gips KW - Bauschuttaufbereitung PY - 2016 SN - 978-0-9573263-1-6 SP - 1 EP - 10 PB - University of Dundee – Concrete Technology Unit CY - Dundee, UK AN - OPUS4-38175 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weimann, Karin A1 - Adam, Christian T1 - Sustainability in the production of recycled concrete aggregates N2 - Concrete is one of the most widely used construction materials and, accordingly, the concrete industry is an important stakeholder in the field of sustainable construction. Therefore various approaches have been implemented to increase the sustainability of concrete. Besides reducing CO2-emissions during cement production, increasing the energy efficiency of buildings and extending their life span, the end-of-life performance of concrete is also an essential aspect of sustainability. Reusing concrete as a secondary building material meets the requirements of sustainability in several ways: the extended time availability of primary raw materials and, thereby, the protection of natural resources as well as conserving landfill site. Furthermore, the production of recycled concrete aggregates (RCA) is a good example for closed-loop recycling. However, regarding the use of RCA as a substitute for natural aggregates in concrete, attention must be paid to all issues of sustainability: this means that environmental, economic and social aspects have to be considered. Since RCA generally have inferior building material properties, such as higher porosity and lower density, the implementation of closed-loop recycling of concrete only makes sense if the technical quality assurance is secured. This paper focusses on the implementation of techniques for the deconstruction/demolition of buildings and the subsequent treatment of concrete rubble in order to improve the building material properties of RCA with regard to the requirements of sustainability and also technical rules and standards. T2 - The 9th International Concrete Conference CY - Dundee, UK DA - 04.07.2016 KW - RCA (Recycled concrete aggregates) KW - Gypsum KW - Selective dismantling KW - CDW treatment KW - Gips KW - Bauschuttaufbereitung PY - 2016 AN - OPUS4-38176 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weimann, Karin A1 - Adam, Christian T1 - Ökobilanzielle Bewertungen von Abbruch- und Aufbereitungsverfahren als Grundlage für ein optimiertes Bauschuttrecycling T2 - 18. Ibausil - Internationale Baustofftagung T2 - 18. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 2012-09-12 KW - Bauschuttaufbereitung KW - Abbruch KW - Ökobilanzielle Bewertung KW - RC-Beton KW - Gips PY - 2012 SN - 978-3-00-034075-8 VL - 2 IS - 3.07 SP - 2-1042 - 2-1049 AN - OPUS4-26606 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -