Rheology Of Cement Paste Containning Chemical Admixtures

Understanding the Rheology of cement and water is a not a simple task since, thebehaviour of complicated system varies with time and there is still a great deal of work to bedone before, it is properly understood. In this study, we used a new simple and cheaptechnique to evaluate flow properties of cement paste .This technique is based on dropping aneedle from a constant height. The penetration depth is measured at different circumstances,different w/c ratios, different types of super plasticizer, and different percentage of admixturefor two types of cement types of cements OPC type V (CEMEX) and OPC type I (HELWAN)were considered in this study. Also, effect of retempering on penetration depth were alsoconsidered. Finally effect of variation of needle drop height was also considered. Thepenetration depth technique proved to be effective in monitoring the effect ofsuperplasticizer/cement ratio percentage, effect of time, manual remixing after 30 minutesand needle drop height on the rheological behavior of different types of cement paste, whichfurther proves the effectiveness of this method in evaluation of cement paste Rheology