20.500.12556/RUL-68744 Influence of superplasticizers on the evolution of ultrasonic P-wave velocity through cement pastes at early age The paper discusses a possibility of using an ultrasonic wave transmission method to study the influence of superplasticizers on the formation of structure of cement pastes at early ages. When compared to mixtures without additives, lower P-wave velocity was found through superplasticized cement pastes, indicating that superplasticizers prevent formation of a solid network frame. Comparing to sulfonate naphthalene-formaldehyde superplasticizers, polycarboxylate ether (PCE) admixtures retarded the solid network frame development more intensively, resulting in a plateau on a P-wave velocity curve during the setting period. The length of the plateau is proportional to the dosage of the PCE and inversely proportional to the specific surface area of the hydration products developed, proving that the specific surface area of a solid phase affects the performance of the PCEs. Validation of ultrasonic results was determined on the basis of the temperature evolution of the material in time. Hydration (A) Microstructure (B) Cement Paste (D) Admixture (D) Ultrasound true false false Elsevier Neznan jezik Neznan jezik Delo ni kategorizirano 2015-07-10 21:11:10 2015-07-10 21:11:10 2022-11-22 11:07:27 0000-00-00 00:00:00 2013 0 0 22-31 51 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 00088846 Trtnik_Turk_CCR.pdf Trtnik_Turk_CCR.pdf 1 AD077E520C33D2B41A4B6B9496BB8BE5 f49b2ad614de254e07eb8f625a2c8c3e7af887b8aa4ad4cad245c55ac357d326 1bdb956f-a1ae-11eb-a523-00155dcfd717 20.500.12556/rul/0e207bcd-9274-41ec-8859-ae6c42584e32 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=85813 Fakulteta za gradbeništvo in geodezijo 0 0 0