The Relation between Concrete, Mortar and Paste Scale Early Age Properties

Materials

Martin Klun¹  Vlatko Bosiljkov¹  Violeta Bokan-Bosiljkov¹ 

[1] Faculty of Civil and Geodetic Engineering, University of Ljubljana, Jamova 2, SI-1000 Ljubljana, Slovenia;

关键词: concrete;    mortar and paste scale of cement-based material;    early hydration stage;    microstructure development;    electrical conductivity;    ultrasonic method;   

DOI  :  10.3390/ma14061569

来源: DOAJ

【 摘 要 】

Microstructure development of concrete, mortar, and paste scale of cement-based material (CBM) during the early hydration stage has a significant impact on CBM’s physical, mechanical, and durability characteristics at the high maturity state. The research was carried out using compositions with increased autogenous shrinkage and extended early age period, proposed within the RRT⁺ programme of the COST Action TU1404. The electrical conductivity method, used to follow the solidification process of CBM, is capable of determining the initial and final setting time, and the end of the solidification process acceleration stage for the paste and mortar scale. Simultaneous ultrasonic P- and S-wave transmission measurements revealed that the ratio of velocities V_P/V_S is highly dependent on the presence of aggregates—it is considerably higher for the paste scale compared to the mortar and concrete scale. The deviation from the otherwise roughly constant ratio V_P/V_S for each scale may indicate cracks in the material. The non-linear correlation between the dynamic and static elastic moduli valid over the three scales was confirmed. Additionally, it was found that the static E-modulus correlates very well with the square of the V_S and that the V_S is highly correlated to the cube compressive strength—but a separate trendline exists for each CBM scale.

【 授权许可】

Unknown