The Regensburg University of Applied Sciences (OTH), in collaboration with the manufacturer of measuring instruments Schleibinger Geräte Teubert u. Greim GmbH, from Buchbach, Germany, have organized the Conference on Rheological Measurements for Mineral Construction Materials for the 28th time. After being welcomed by OTH President Prof. Dr. Baier, the event was conducted, as in previous years, by Prof. Dr. Wolfgang Kusterle from the Faculty of Construction Engineering and Dipl.-Ing. Markus Greim, Managing Director of the manufacturer of measuring instruments. The latter assumed most of the subsequent moderation, which in particular included the brief rounds of questions that followed every lecture. Prof. Kusterle, in his welcoming speech, noted with regret the small number of representatives from the industry, but was pleased by the large and enthusiastic attendance of recent graduates and students from the university, which filled the auditorium. Also present were the sponsors of the event, the companies Schleibinger Geräte GmbH from Buchbach, Kniele GmbH from Bad Buchau and C3 Prozess- und Analysentechnik GmbH from Munich.
The international orientation of the event was highly apparent: three of the ten lectures were held by international speakers, with five additional lectures by German scientists in English.
Distinct international orientation
The first speech was given by Mareike Thiedeitz, M.Sc. of Munich University of Applied Sciences (MUAS), who in her lecture discussed the influence of mixing time on the rheological parameters of the concrete matrix. Małgorzata Gołaszewska, M.Sc.Eng., of the Silesian University of Technology in Gliwice, Poland, held the second speech. She discussed the rheological influence of limestone in concrete. Dr.-Ing. Wibke Hermerschmidt, in the third lecture, talked about the influence of the slump of flowable mortars and concretes on their rheological properties.
Dr. Oliver Mazanec, Production Manager from BASF Construction, demonstrated improved mixing methods for enhancing the rheological properties of concretes placed through a funnel. The experiments involved here were carried out on especially deep foundations for which the concrete pump had to overcome a high drop height.
After the lunch break, the event continued with a lecture by Dr.-Ing. Christan Baumert from the Institute of Construction Materials at the University of Stuttgart. In his lecture on shear-induced particle migration and its relevance for rheological measurements on mortars and concretes, he demonstrated an innovative measuring instrument. The Institute, headed by Prof. Dr.-Ing. Harald Garrecht, where he works as senior scientist, developed, in collaboration with the company Kniele GmbH, the KKM-RT 22.5/15 and has now brought it to market maturity.
Then, Dimitri Feys took the podium; he is Assistant Professor at the Missouri University of Science in Rolla, USA. He elaborated on the link between rheology and sustainability and focused on the resistance of self-compacting concrete (SCC) to frost and freeze-thaw cycles with de-icing salt. In this context, within the scope of his research, he determined the degree of deformation of air bubbles during the setting process of concrete and took this into account for rheological assessments.
B. Eng. Ludwig Hertwig of HTWK Leipzig devotes his research to injection of concrete into narrow formwork and the rheological consequences of this procedure. His ongoing research is in particular directed toward optimizing the production of extremely thin-walled concrete components such as fiber-reinforced façade shells. His findings could in the long term provide new insights into new production methods for precast elements.
The last presentation of the conference was held by Maria Thumann, research assistant in the Laboratory for Concrete Technology at OHT Regensburg. Her presentation ingeniously combined the two large research fields of the head of the department, Prof. Dr. Kusterle: Rheology And Shotcrete.
In addition to the program of lectures, the participants were offered an accompanying trade exhibition in the foyer of OTH Regensburg.
Text: Robert Mehl, Aachen