yes, if it is before the initial setting time...
No, you cannot reuse the cement after it has crossed the setting time.
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..
An arbitrary division has been made for the setting time of cement as initial setting time and final setting time.It is difficult to draw a rigid line between these two arbitrary divisions.For convenience,initial setting time is regarded as the time elapsed between the moment that the water is added to the cement,to the time that the paste starts losing its plasticity.The final setting time is the time elapsed between the moment that the water is added to the cement ,and the time when the paste has completely lost its plasticity and has attained sufficient firmness to resist certain definite pressure.
You could add lime putty. But the best solution would be to get a cement that sets in the amount of time you need, a 'slow setting cement'.
Please note that a key correction in terminology is essential before your question can be answered: use the word "concrete" instead of "cement." The answer is to modify your mix (i.e. Portland cement, sand, gravel, and water) by using hydraulic cement to repace part of the Portland cement. The higher the amount of hydraulic cement you add, the quicker the setting time and the impermeability. However, hydraulic cement sets so quickly that you have limit the amount of total mix so as to be able to pour it and form it before it sets.
The initial setting time of cement is 30 minutesThe final setting time of the cement is 10 hours.The initial and final setting time of the cement can be found by using the Vicat's apparatus.
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.
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.
initialy setting time up to 10min. & final setting time upto 10 hours
Gypsum is added to cement to decrease the setting time.
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..
retarder increases time to set, accelerator decreases 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".
An arbitrary division has been made for the setting time of cement as initial setting time and final setting time.It is difficult to draw a rigid line between these two arbitrary divisions.For convenience,initial setting time is regarded as the time elapsed between the moment that the water is added to the cement,to the time that the paste starts losing its plasticity.The final setting time is the time elapsed between the moment that the water is added to the cement ,and the time when the paste has completely lost its plasticity and has attained sufficient firmness to resist certain definite pressure.
does this cement satisfy ASTM standard requirements for normal consistency
vicats apparatus is used for initial setting time of cement.