Properties Of High Performance Concrete: The Effect Of Cracks
Free (open access)
E. Mňahončáková, M. Jiřičková & R. Černý
The moisture transport and storage parameters of high performance concrete belong to the most critical parameters in designing and using complex reliability based models for service life prediction of concrete structures. However, mostly it is supposed that the material is compact without any significant cracks, which is not always true. In this paper, the effect of thermally induced cracks on the basic moisture transport and storage properties is analyzed. Experimental results show that the presence of cracks in hardened high performance concrete mixtures dramatically changes all measured hygric parameters. Also, the effects of both microsilica and the size and presence of aggregates on moisture transport and storage parameters are very important. The liquid water transport is found to be affected by cracks, microsilica and aggregates in a much more significant way than water vapour transport. Keywords: high performance concrete, moisture transport and storage properties, cracks. 1 Introduction The progressive building materials development improves their quality and utility value. In order to achieve better material properties, besides the new technologies also specific admixtures are employed. The accurate admixtures dosage and technological conditions observation can improve the material parameters like strength and durability. Most frequently, the mineral admixtures, for example pozzolana, fly ash or flue cinder, are used in concrete production. Fine siliceous materials usually called silica fume belong to relatively newly applied materials improving concrete quality.
high performance concrete, moisture transport and storage properties, cracks.