yes I'm also little confused ..
gypsum increase the setting time of cement.
because when we know the setting time of cement we easily identified that where can we use the cement according to there setting time.
When cement is mixed with water, it forms slurry which gradually becomes less plastic with the passage of time & finally a hard mass is obtained. In this process, at a certain stage when the cement paste is sufficiently rigid to withstand a definite amount of Pressure, it is said to have set & the time required to reach this stage is termed as "setting time".
There are 15 types of cements such as-1.)O P C cement, 2.) P P C cement 3.) Low heat cement 4.) Quick setting cement 5.) White cement 6.) Coloured cement. 7.) Blust Furnace Slag cement and so on
vicats apparatus is used for initial setting time of cement.
False-setting is when cement abnormally and prematurely sets.
False set is caused by having too much hemihydrate of calcium sulfate. It does not produce much heat. Flash set produces a lot of heat and is caused by a lack of calcium sulfate.
gypsum increase the setting time of cement.
because when we know the setting time of cement we easily identified that where can we use the cement according to there setting time.
yes, if it is before the initial setting time...
3% of gypsum is added to cement to "prevent the rapid setting of cement"
how the water mixed with cement affects the time of its setting
because when we know the setting time of cement we easily identified that where can we use the cement according to there setting time.
The construction industry uses both the natural and the synthetic forms of gypsum in Portland cement manufacturing. Although the amount of gypsum used in the mix represents a small percentage of the volume of all ingredients, gypsum has important functions.
Gypsum is added to cement to decrease the setting time.
The properties of cement are,Chemical compositionLoss on ignitionInsoluble residuessulphur content and magnesia contentSoundnessHeat of hydrationSetting timeInitial setting timeFinal Setting timeFinenessStrength of cementConsistency.
It's the time from which cement starts the setting process after water is added.. Usually it is 30 min.. It can be delayed or advanced using chemicals..