TY - CONF A1 - Brigzinsky, Maria A1 - Hünger, Klaus-Jürgen T1 - Extruded lime-rich fly ash-clay mictures for the use in "cold ceramics" bricks T2 - 2nd International Conference on Advances in Cement and Concrete Technology in Africa N2 - There is a huge potential for the resource conservation and for reduction of CO2 emissions by using industrial by-products, as well as natural slags or ashes in a precise and high-class manner. Apart from mineral coal fly ash, which is used and certificated as an additive for concrete, especially lime- rich fly ashes with their latent hydraulic and puzzolanic properties offer a variety of possibilities in the high quality production of small-sized components like bricks. Fine-grain-mixtures from different clays and fly ashes were homogenized and plasticized by the addition of water in an Eirich-mixer. The added amount of ash was varied from 10 to 30 wt%. Out of these mixtures, test items with a sufficient strength for transport were moulded in an extrusion process. The test samples were stored under various humidity conditions (RH= 33, 65 and 88 %) at 20 °C and, subsequently after different times of self-hardening (28, 70 and 105 days), tested on their strength and durability. Compressive strength up to 15 MPa was achieved. In order to reach that result, at least 20 wt% of the clay should be substituted by ash to get an increase in strength compared to the pure clay samples. Further examinations have shown that it is possible to prevent the destruction by capillary water absorption of pure clay/loam specimens by an optimal use of ash in the recipes. Overall, it can be stated that due to the self-hardening potential of these mixtures there is no need for an energy-intensive and highly CO2 emitting combustion process, if the clay is substituted in fine grain mixtures by high lime component fly ashes. KW - Waste materials KW - Fly ash KW - Self-hardening bricks KW - CO2-reduction KW - Resource conservation KW - Enhancing durability Y1 - 2018 UR - https://opus4.kobv.de/opus4-UBICO/frontdoor/index/index/docId/21302 SN - 978-3-9817502-3-2 SP - 545 EP - 552 PB - BAM Bundesanstalt für Materialforschung und –prüfung CY - Berlin ER -