Procedure for Initial Setting Time Test:
For determining the initial setting time of cement paste, set the 1mm. diameter needle on the lower end of the rod.
Now release the rod for 30 seconds and note the time at which the needle was released, record this in the table along with the penetration of needle in the paste.
After periodic time again release the rod for 30 seconds note the penetration of the needle in paste.
Repeat the above step until the penetration becomes just 25 mm. which is ASTM standard. Calculate the total time up to this step, which will be the initial setting time of the cement. Compare it with the standard time and give comments.
Procedure for Final Setting Time Test:
For determining the final setting time of cement paste, set the 5 mm diameter needle on the lower end of the rod.
Now again repeat the above steps for noting the final setting time of cement.
The final setting time will be noted when the needle if released doesn’t sink visibly and leaves no impression on the surface of the paste.
Then compare it with the ASTM standard time. The final setting time can be found by the formula:
Final setting time = 90 + 1.2 (initial setting time)