TY - CONF A1 - Schmidt, Wolfram A1 - Tchetgnia Ngassam, I. L. A1 - Mbugua, R. A1 - Olonade, K. A. A2 - Greim, M. A2 - Kusterle, W. A2 - Teubert, O. T1 - Natural rheology modifying admixtures for concrete T2 - Tagungsband zum 26. Workshop und Kolloquium "Rheologische Messungen an Baustoffen" N2 - The possibility to tailor the rheology of concrete eventually opened up the path to new technologies, where design criteria are no longer limited to the compressive strength. Thus, it can be concluded that the capability to control the rheology of concrete can be considered as catalyst for many of today’s concrete innovations. In the same way rheology modifying admixtures will be key to mastering the challenges of the next decades. In many regions of the Southern hemisphere, the effective use of chemical admixtures would significantly contribute to solve problems induced by the challenging climate, but particularly in Africa there is often a lack of local supply and supply infrastructure. In Africa, concrete admixtures are largely shipped or transported from outside the continent. The long distance transportation of chemicals is not very environmentally friendly and the economic consequences are dramatic: the agents are difficult to purchase, expensive, and there is no large variety of products available in the market. Due to the enormous relevance of rheology modifying admixtures, it is worthwhile to recollect that nature provides an enormous variety of chemicals that can be used readily or with low processing and without enormous transportation distances, since these plants are typically regionally abundantly available, cheap, and they are environmental friendly. The paper presents an overview of various options for rheology modifying admixtures, that can be found in Africa, and that may become a real alternative, once their interaction within the complex cementitious system is well understood. PB - tredition GmbH CY - Hamburg T2 - 26. Workshop und Kolloquium "Rheologische Messungen an Baustoffen" CY - Regensburg, Germany DA - 21.02.2017 KW - Concrete KW - Rheology PY - 2017 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/40599 AN - OPUS4-40599 SN - 978-3-7439-0171-1 SP - 75 EP - 87 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany