University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Guenter Mair
(2010):
Eignung der Betonfilterpresse für den Nachweis der Frischmörtelstabilität zur Herstellung mantelverpresster duktiler Rammphähle.
Master / Diploma Thesis - Institut für Geotechnik (IGT),
BOKU-Universität für Bodenkultur,
pp 148.
UB BOKU
obvsg
- Abstract:
- Bleeding in mortar or concrete may cause damage in foundation engineering. Bleeding is mainly caused by consolidation and settling of the solid particles in the solid / liquid system. In pile foundations, mortar according to special recipes is often used and there is no unified standard for quality control against bleeding. A mobile testing device was developed at BPV (Bautechnische Prüf- und Versuchsanstalt), which consists of a pressurized chamber with an opening at the bottom. The amount of water from the mortar / concrete under pneumatic pressure is measured and provides some indication of the susceptibility of the mortar/concrete to bleeding.The mobile bleeding tester is an important contribution to quality control. How-ever, the mechanism of water migration within the sample is not yet clear and a sound theoretical model for bleeding is not available. In order to understand the dynamics of pore water pressure, the mobile bleeding tester is equipped with a pressure transducer. Some bleeding tests are carried out on mortar of three different recipes. The grain distribution curves of these mortars are compared and their bleeding behaviour is optimized with reference to Fuller’s curve. The samples are dried after the tests. The grain distributions in the upper and lower part of the samples are determined in order to find out whether the migration of fines occurs during the bleeding tests.
- Beurteilende(r): Wu Wei